Airflow patterns within the hospital operating rooms (OR) determine the levels of air speed, temperature, and flow path of contaminants to and from the sterile and non-sterile zones. This paper with the help Computational Fluid Dynamics (CFD) analysis analyzes the effect of various HVAC configurations on the resulting airflow pattern, temperature distribution, and importantly flow of path of contaminants between the sterile and non-sterile zones. With the help of airflow visualization this paper shows the effective flow path of the contaminants. The analysis provided in this paper is useful to practicing engineers in the healthcare industry in designing the HVAC systems for the operating rooms.

An Efficient ventilation configuration of an Airborne Infection Isolation Room (AIIR) is essential for protecting Health care workers (HCW) from exposure to potentially-infectious patient aerosol. This paper presents the Computational Fluid Dynamics (CFD) study to predict airflow distribution patterns throughout the AIIR, air velocity vectors in the HCW’s region, streamline of an air particle from patient’s infectious source and the comfort working conditions for the HCW for a range of AIIR ventilation configuration design challenge.

Buildings impact human health. The design and operation of an indoor environment influences occupants’ well-being. Aerosol transmission has been defined as “person ­to ­person transmission of pathogens through the air by means of inhalation of infectious particles”. The source may be an infected person such as a flu sufferer sneezing. Aerosol generation can also happen via coughing, laughing or just exhaling. This paper focuses on investigating the spread of aerosols after sneezing in a ventilated office space and the length of time they reside in the breathing zone thus estimating the possibility of infection of another occupant.

High profile targets for biological and chemical attack are relatively easy to identify and thus provide appropriate protection. However, a low but real risk is present for many other commercial buildings, particularly those that have large numbers of occupants (so called soft targets). The low probability of such an event, combined with the high cost of sensors capable of confirming the presence of hazardous agents are problematic for widespread adoption. Consequently, DHS is studying technology that could both detect hazardous agents in buildings and improve the performance of existing life safety systems, at minimal additional cost to the building owner.

This presentation provides an overview of the need and prospects for low cost biological and chemical agent detection from the perspective of the DOD.

A methodology to determine automated heating, ventilation and air conditioning (HVAC) system and building response mitigations for bio-aerosol or chemical threats in commercial buildings is under development at Pacific Northwest National Laboratory (PNNL). Models of indoor contaminant dispersion are used to identify and respond to threats based on distributed sensor data. Model scenario verification will be performed; however, validation will be limited to agent surrogates.

Computer flow network models and experiment are used to create a release of a chemical/biological surrogate agent and understand its propagation in a commercial office building. Manipulation of the building HVAC system is used to mitigate the spread of the surrogate and limits its possible effects on building occupants.

In the past, the International Building Code (IBC) has required pressurized stairwells to maintain pressurization with all exit doors closed. Most jurisdictions in the U.S. are adopting the 2015 IBC that considers the status of exterior doors as opened or closed. A 2016 ASHRAE research project (RP-1447) has shown that a tenable environment can be maintained in stairwells with many open doors provided that the stair doors on the fire floor are closed. Smoke that leaks into the stairwell is quickly diluted resulting in a tenable environment in the stairwell. There are stairwell systems that are intended to maintain pressurization with a number of open doors, but many such systems are complex and have dangerous failure modes. This paper discusses these issues including suggested stairwell pressurization systems.

Delhi Metro is the world’s thirteenth largest metro system in terms of length and is India's first modern public transportation system built on state of the art technologies. The life safety systems are of paramount importance while carrying millions of passengers daily, the systems are required to be designed in such a manner that in case of any emergency situation the passengers shall be safely evacuated from transit network in minimum time. This paper discusses in detail the different life safety systems provided in the underground metro station building e.g. Smoke Management System, Fire Fighting System, Fire Alarm System, Emergency Power Supply System and Emergency Lighting System.

Mechanical Emergency Ventilation Systems (EVS) have been widely used in tunnels to mitigate fire hazards. However, a number of catastrophic tunnel fires have occurred and have raised questions about the effectiveness of the current tunnel fire safety systems. This paper discusses life safety issues that need to be considered in designing different types of the EVS commonly used in tunnels including transverse and longitudinal ventilation systems. It also discusses how airflow induced by the longitudinal and transverse ventilation systems could impact on the fire development and smoke dispersion in the tunnel. Tenability along the length of the tunnel produced by each type of the ventilation systems is also examined.

Superstorm Sandy provided an extreme climate event to learn many lessons on how buildings were designed and how they operated during and in the aftermath of Hurricane Sandy. This includes the infrastructure that is so vital to the operation of Buildings and their HVAC&R systems.

Discuss of NYC sustainability and resilency strategies during and in the aftermath of Hurricane Sandy. New codes and design requirements to strengthen the HVAC&R and life safety systems of buildings during extreme climate events.

Discuss the issues and situations that occurred at NYU Medical during Superstorm Sandy in regard to life safety and HVAC&R. Infrastructure design changes to reduce/eliminate the effects of future flooding/climatic events. Discuss how NYU achieved significant energy savings and energy reduction, while reducing its carbon footprint.

This presentation discusses the history of climate change and the founding scientists whom developed instrumentation to measure climate change predictors and parameters, i.e., ozone depletion, global warming, CO2 levels, etc.

Tenability analysis along with computational fluid dynamics (CFD) are recognized methods of atrium smoke control analysis by NFPA 92, Standard for Smoke Control Systems. Tenability analysis evaluates the following threats to life: toxic gas exposure, heat exposure, thermal radiation exposure, and reduced visibility. In dense smoke, people see poorly and often become disoriented which prolongs exposure time of the other threats. Also falls from balconies can result from reduced visibility. This paper discusses these threats as they apply to atria smoke control and how tenability analysis can be incorporated in CFD simulations of atrium smoke control systems.

High-rise building fires often lead to disastrous and enormous losses if the fire smoke is not well controlled. This study uses the CFD model, Fire Dynamics Simulator (FDS) developed by the US National Institute of Standards and Technology (NIST), to model the fire smoke spreads and control strategies in a full-size high-rise building. The building is a 302-feet (92 meter) high-rise with two 20-story towers, three-story ground level parking spaces, two stairwells and one elevator shaft. The modeled fire smoke control system is a hybrid venting system with mechanical fan installed at the top of the stairwells. Neutral plane level, smoke temperature and smoke flow inside the building were studied based on the simulation.

The International Building Code and the Life Safety Code (NFPA 101) recognize that smoke-protected assembly seating, which is not subjected to smoke accumulation within or under a structure, subjects occupants to a lesser hazard from the accumulation of smoke and fumes during a fire event. The codes therefore have less-stringent requirements for design and layout of the means of egress for smoke-protected assembly seating, including reduced aisle widths per seat served and greater maximum travel distances. These less-stringent requirements provide increased use of space and flexibility in the design of assembly seating. This paper provides an overview of the use of CFD models in the design of smoke control systems for smoke-protected seating. Examples of smoke-protected seating in various settings, including arena seating and large theaters, are also discussed.

Commissioning is a process for ensuring that a system is designed and operated as intended; commissioning helps achieve larger goals of sustainable design and operation, Life Cycle Cost (LCC) effectiveness, efficient use of investments, minimizing overall maintenance and utility costs, component life reliability and performance expectations. AiCARR, ASHRAE and CIBSE have agreed to draw from definitions and terminology that appear in their publications or in their other resources for the purpose of harmonization by developing a first collective work on the topic. This workshop presents the state of terminology in each country and a proposal for a common overview.

Commissioning is a process for ensuring that a system is designed and operated as intended; commissioning helps achieve larger goals of sustainable design and operation, Life Cycle Cost (LCC) effectiveness, efficient use of investments, minimizing overall maintenance and utility costs, component life reliability and performance expectations. AiCARR, ASHRAE and CIBSE have agreed to draw from definitions and terminology that appear in their publications or in their other resources for the purpose of harmonization by developing a first collective work on the topic. This workshop presents the state of terminology in each country and a proposal for a common overview.

This seminar focuses on a specific project for a new laboratory building for a major cancer research institution. Specifically, the presentation discusses energy recovery, demand based ventilation, occupancy sequencing and building pressurization strategies that were implemented and the lessons learned during commissioning of the HVAC systems.

There are a multitude of challenges associated with designing, constructing and operating BSL-3 laboratories. The combination of user expectations, regulatory compliance, risk considerations and contractor interpretation of specifications can result in a delay in opening these laboratories from 1-2 years or longer. This presentation discusses the practical implications of commissioning BSL3 laboratories. It will provide an overview of the different organizations providing regulatory compliance, discuss the various risk factors involved with programmatic decision making, review engineered systems and ventilation strategies and the impact these decisions have on operational strategies. This presentation highlights essential documentation for sustainable operation.

Building EQ has many new features and offers support for ASHRAE members in their energy savings efforts. The most prominent change is that data will be entered through a web portal rather than filling out a spreadsheet. New marketing tools will be provided to members as the year progresses.

Adapt Building EQ provides a college senior-level undergraduate or graduate course on building energy auditing and analysis using the ASHRAE Building EQ rating system as a learning framework. Students will experience project-based learning through hands-on engineering in real buildings under the guidance of industry professionals. The course is nominally three semester credit hours. It involves 10 weeks of classroom instruction followed by five weeks of hands-on field work in teams under the guidance of local industry mentors. Course content will be freely available through ASHRAE student branches. Students will be expected to purchase some resources through ASHRAE with student discounts.

The ASHRAE Building EQ program benefits owners and managers of building portfolios. For each building, the program provides an energy rating along with actionable recommendations to improve building performance. These recommendations are made by a professional assessment of a building’s energy use as determined by In Operation and/or As Designed ratings method. Building EQ is the only rating system that offers both methods with a consistent baseline to make comparisons along with detailed actionable recommendations. ASHRAE entered into an agreement with APPA in July 2016 with the commitment to cooperate across many areas including implementing Building EQ on university campuses.

APPA is the preeminent organization for university facilities management in North America. APPA has 15,000 members at 1400 institutions. APPA is keenly interested in transforming the way we look at performance of buildings. APPA entered into an agreement with ASHRAE to cooperate in areas of mutual interest. Building EQ offers one opportunity to advance facilities management and help positively shape our current and future built environment.

The commercial kitchen ventilation (CKV) system is just that, a system, complete with hoods, exhaust and makeup air fans, makeup air conditioning and delivery and in many cases, demand-based controls. Simply stated, when commissioning (Cx) is compromised, CKV performance falls short of client expectations! Unfortunately, commissioning a CKV system is a complex, multi-phase task not always understood by the design community. Many times, the failure of an exhaust hood to capture effluent from the cooking process could have been mitigated through effective commissioning. This is a high-level perspective on the commissioning process applied to a commercial kitchen.

What are the common issues typically found while performing a test and balance of a CKV system? Several examples are presented that display the common issues found when performing a test and balance as part of both new construction and rebalancing of existing sites due to inadequate design, improper installation and poor maintenance.

Commercial kitchen ventilation systems (CKV) are a subset within the overall building HVAC, which requires a proper approach to system design, installation and commissioning for operation and performance. System design, quality products and integration are critical; however, the realities of field installations shows that, “where the rubber meets the road, your mileage may vary.” This seminar highlights many of the common issues discovered in the field when performing a system design verification to ensure proper and sustainable operation.

Participants will gain a better understanding of commissioning deliverables from the CxA and/or construction team to be passed to operations. An effective operation and maintenance program benefits when all relevant deliverables are received at project turnover, bridging a commonly experienced gap in information. It is also important to identify what documentation will benefit the relevant committees in their guidance to professionals in creating and receiving those deliverables. ASHRAE recently issued Guideline 1.4 on the Systems Manual. Is this a good starting point for documentation or just another formalization of process? This speaker examines the consultant's perspective.

Higher education projects are normally required to obtain a LEED certification. Embracing LEED requirements is challenging; but many are now convinced that it can significantly improve operations! LEED projects produce commissioning deliverables that are currently underutilized in bridging the gap to operations management. A higher level of awareness and improved implementation of the Final Commissioning Report and Systems Manual deliverables will greatly improve communication from schematic design through long term operation of the building. Developing an Owner’s Project Requirement (OPR) early will ensure that what is proposed in the design and constructed can be maintained well at a low cost.

It is often said that improvements in building operations can yield 10 – 20% energy savings. Effective Building Re-tuning (BRT) techniques developed by Pacific Northwest National Laboratory that identify energy efficiency opportunities rely on data from a Building Automation Systems. Unfortunately, many buildings have no such trending abilities. Using loggers, sensors and a methodology, BRT-like measures developed by CUNY Building Performance Laboratory identifies operational improvements across building systems. This seminar describes CUNY BPL’s experience creating and applying solutions to many building systems; it also speaks to the potential for automation to reduce operator effort in acquiring recommendations for operational improvements.

A case study is examined where the information gap between construction and operations was successfully bridged at the commissioning phase of a project utilizing a tablet-based information portal on the owner's cloud. In this example, operational information which is critical to thermal comfort and energy performance was effectively communicated and leveraged a video archive. The necessity of this communication occurs not only at the commissioning phase and project turnover to operations but also serves as a useful information resource for the life of the facility and its systems.

This workshop includes the building owner's perspective on the definition of OPR, why the OPR is important and summarizes their responsibilities in developing the OPR. Key points to be discussed are: The communication gap between Owner, Designer and Cx provider; Who takes (or should take) the lead? The audience will break into small groups and provide an opaque OPR. The Owner and Cx provider will have a pre-written script and play the role of an Owner of a commercial office building. The groups will interview the Owner and rewrite the section of the OPR to reflect the actual needs of the Owner. The Cx provider will then present an example of an effective OPR, stimulate open discussion and questions and compare the example OPR against a selected group's document.

An experienced commissioning (Cx) provider shares their perspective on the definition of OPR, why the OPR is important and summarizes the essential components. Key points to be discussed are: A clear definition of the Owner's expectations reduces the risk of unclear intent, unfulfilled expectations and unnecessary disputes; An OPR that reflects the actual needs of the Owner, the users or occupants, and facility staff is needed for Cx to be successful.

National labs, universities, and industry are all developing significant capabilities for urban-scale building energy modeling…once a virtual city is constructed. To construct the models, most rely on local data sources that work at the scale of a city or county (such as a tax assessor’s database) or flyover of the area of interest, but do not use data sources or algorithms that would scale to areas the size of a metropolis, state, or entire country. This presentation will show recent advances in scalable capabilities for automatically creating fully-articulated OpenStudio and EnergyPlus models of individual buildings for any area of interest.

A building’s façade is a major element that accounts for 70% of building energy performance. Compared with the internal mechanical system and operation schedule, façade features information is relatively easy to obtain from the visual aspects of a building. Instead of using traditional and complicated simulation methods, a mathematical model can be established to estimate EUI baselines based on sufficient existing building practices data. This prediction modeling approach will provide a more realistic EUI estimation tool for calculating an energy use baseline and will enable real-time energy usage monitoring and management of each targeted building.

Buildings in cities consume 30 to 70% of the cities’ total primary energy. Retrofitting the existing building stock to improve energy efficiency and reduce energy use is necessary to reduce green-house-gas emissions and mitigate climate change. We present a case study on district-scale energy retrofit analysis using CityBES, a web-based toolkit developed by LBNL. Two retrofit scenarios are studied: evaluating energy savings and cost of typical energy conservation measures (ECMs) for a portfolio of hundreds of buildings in downtown San Francisco; and optimizing a package of ECMs that can achieve 50% energy savings for all buildings in the district.

New steam boilers and hot water boilers need special attention paid to the application of water treatment during the startup/commissioning process. Proper cleaning and passivation during the startup will prevent equipment failures or poor energy performance. Steps to prevent mineral scale and corrosion should be implemented as soon as water is introduced into these systems. This seminar provides guidance (with checklist) on the steps required to prepare the boiler systems for service.

New cooling towers, evaporative condensers, fluid coolers, piping and chiller equipment must be commissioned properly to control waterside problems that will reduce equipment life, efficiency, reliability and safety. Proper startup and commissioning is especially important to reduce the potential for white rust corrosion in new cooling water systems containing galvanized metallurgy. This seminar explains the proper commissioning of new or retrofitted cooling water system construction projects and how to avoid costly damages and potential litigation due to uncontrolled water chemistry.

When building water system Legionnaires' disease outbreaks occur no matter how long after construction or renovation, commonly those involved in design and construction are named parties should subsequent litigation occur. And when building water system Legionnaires' disease outbreaks occur within one year of construction or renovation almost always those involved in design and construction are primary named parties should subsequent litigation occur. This seminar covers simple and easy steps to validate that critical commissioning steps of aerosolizing water systems have been completed and are properly documented to insure compliance with ASHRAE 188 and industry best practices.

This presentation covers the approach, methodology and lessons learned of a performance-based chiller retrofit project. The performance evaluation included a life-cycle cost assessment of replacement options that involved a data-driven energy model and an accurate understanding of the baseline energy consumption in the existing condition through a building survey and detailed trend analysis. Lessons learned from construction oversight and performance-based commissioning is also presented.

This presentation includes a discussion regarding the role of the EOR in bridging the process that begins with the owner, continues through design, construction and commissioning and ends with the delivery of a fully tested and operational facility. The discussion includes issues linking the EOR and the CxA, including how and when the CxA should be introduced into the design process, how the design and specifications should provide “hooks” to clearly designate to the contractors and subcontractors their own responsibilities to the CxA Team and the CxA Process and what can go wrong when those issues are omitted.

The presentation includes a discussion regarding the role of the commissioning agent and what information is required from both the Owner and EOR to facilitate a successful commissioning program. It also discusses how and why the CxA must remain independent of the EOR while also teaming with the EOR and the entire project team to facilitate a win-win outcome. The presentation explains how expanding the traditional scope of commissioning can be made to easily include leading the effort to deliver the needed FM/O&M programs, procedures and training.

Taking on an energy management program of a large campus or portfolio of properties can be a daunting task. Rather than “putting out fires” by approaching projects independently, this study analyzes a strategic, deliberate approach to achieving institutional energy cost reduction through a repeatable, stepwise roadmap plan that involves financial planning, needs assessments, prioritization and implementation of audits, retro-commissioning and measures. Setting up your plan allows you to actually predict the impact of the optimization process.

Seriously, how do you approach RetroCx of a 30,000 ton chiller plant? We will take a deep dive into a University of Arizona campus chilled water plant that includes 22 chillers and 300 ice storage tanks. The discussion covers the process and findings of the work which includes the load management and chiller staging to improve plant efficiency. It also covers the field modifications completed at the plant to implement the RetroCx measures. Finally it discusses the OnGoing Monitoring based Cx that has further optimized the plant.

How you look for optimization opportunities and present the value takes special care to ensure buy-in from owners and operators. This study focuses on how to hunt down measures, present them with confidence, ensure successful implementation and verify results. Specific examples from large commercial buildings are presented.

Agent based modeling (ABM) is a bottom-up method of modeling complex systems that simulates the actions and interactions of autonomous agents. ABM is being used to look at consumer adoption of technologies ranging from cosmetics to electric vehicles and are often used as a replacement for diffusion models. This seminar presents the use of ABM to estimate the adoption of energy efficient building technologies. In the model, building owners make decisions based on a wide variety of economic and non-economic factors. A study of the nationwide adoption of hot water heating technology is shown.

With the advent of urban scale reality models, creating community, campus or Urban Building Energy Models (UBEM) has become as easy as a few hours of capturing photos with a drone. Combining the virtual model with benchmarking, facility, utility, management data and BIM models allows data to be easily queried. This presentation demonstrates several examples of how UBEM can visualize and report on benchmarking, utility and facility management data at the community, campus or urban scale. Virtual navigation of a campus and several cities will demonstrate how UBEM can be used to measure, analyze and report readily available urban data.

This session will cover the integration, interoperability and system architecture of a smart city. The presenter discusses new opportunities for connected cities using broadband communications and a vision for new solutions. Street lighting is central to a broader smart city vision that municipalities are starting to embrace in order to reduce energy and operational costs.

This seminar will showcase what makes San Diego one of the most innovative, forward-thinking cities in smart infrastructure technology. The presenter explains how energy-efficient LED street lighting fixtures and wireless lighting controls will save the city more than $250,000 annually. The seminar describes a streetlight network that also controls holiday lights, contains chemical sensors to monitor and alert of air quality and toxic spills, provide Wi-Fi to low income neighborhoods, enhance cellular service with micro cells, act as electric vehicle (EV) charging stations and more.

This presentation introduces an integrated technology that utilizes smart plugs as occupancy sensors, along with low-cost virtual outdoor-air flow rate and thermal energy meters for energy efficient operations and detection of energy faults of air handling units (AHU) or rooftop units. The smart plug uses power measurements coupled with occupancy sensors to accurately infer occupancy. The virtual meters determine outdoor-air flow rate and thermal energy use in AHUs indirectly through control valve, outdoor air damper and fan operation variables, which are readily obtained. The technology integrates plug load systems with HVAC systems in commercial buildings to enhance energy performance.

IOT devices can measure energy use and other parameters accurately. Then the data will be pushed to cloud and analyzed using machine learning and artificial intelligence. The energy use is optimized with automatic and intelligent control strategies.

This presentation discusses several recent R&D efforts at NREL which showcase opportunities for internet-connected residential HVAC and other "smart appliances" to cost-effectively provide mutual benefits to homeowners and utility systems. These include a Time-Of-Use study on HVAC interactions with the electric distribution system, a demonstration of residential equipment providing frequency regulation and a home energy management system which delivers reliable demand response without any reduction in homeowner comfort.

This seminar discusses current issues of control networking security standards for Building Automation solutions and the need for cybersecurity best practices. As more devices are connected to the building network requiring access to the BAS and then to the Internet, the greater the opportunity for exploitation of both internal and external network access. IoT technologies provide direct access from a cloud service to a device, in many cases, bypassing the constraints set up by IT. This session discusses risks and opportunities associated with cybersecurity and efforts to develop smart building specifications to minimize the potential risks while balancing the desire for new solutions.

In every cyber security standard there is a common step, the “Risk assessment”. But what is a risk assessment and how do I do one? This presentation explains how to perform a risk assessment. This information helps the building owner, design engineer and automation professional determine the value of cyber security.

This seminar discusses important system engineering and fundamental topics related to HVAC system security. Key issues of cybersecurity risk analysis, threat model and system security design principles are discussed.

This seminar discusses issues related to building automation security testing and information existing industrial cybersecurity standard IEC 62443 and related certification.

Using natural ventilation is a primary strategy for low energy design. A common strategy is to combine natural ventilation with active heating and cooling systems resulting in mixed mode buildings which inherently have an additional level of control sophistication. This presentation tracks three case studies of the success and lessons learned from mixed mode buildings. The presentation reviews how occupants engage with and interpret mixed mode building operations including successes and learned experiences.

As more buildings strive towards net-zero energy consumption and seek to connect occupants with nature, natural ventilation is attracting more interest. This presentation explains the benefits of natural ventilation and the corresponding control design objectives. Challenges and lessons learned will be shared from a mid-rise office building, university dorms, several condos and academic buildings including sensing, occupant behavior, BAS interfacing, controlling night purge, tenant complexities and optimizing hybrid systems. The completed projects illustrate another practical key to success: designing control strategies that survive value engineering.

Using natural light in buildings can save energy but only if systems are controlled to accomplish the savings. Natural light can enhance the occupant’s impression of a space but only if they can adjust it to suit their preferences. A state-of-the art control system for lighting and dynamic shading handles diverse considerations: inputs from occupants, dynamic daylight conditions, thermal and electrical energy flows, scheduled and unscheduled use of the space. This presentation explains control features and the advantages of implementing them in an integrated BAS. Data from recent projects illustrates the benefits.

Model predictive control (MPC) is becoming a popular algorithm for building HVAC supervisory control. One type of MPC for HVAC supervisory control is EnergyPlus Model-based Predictive Control (EPMPC), where an EnergyPlus model is used in MPC algorithm to predict future building performance. EPMPC could reduce the development cost of MPC by reusing the EnergyPlus model that is often developed during the design phase of a project. However, MPC, especially EPMPC, is much more complex and computation-intensive compared to traditional HVAC control logic; also, it needs to constantly acquire updated forecast data as inputs for computation, such as weather forecast data and occupancy schedule forecast data. Therefore, implementation of MPC to real HVAC systems is difficult. In this paper, a software framework of MPC for HVAC supervisory control is developed to facilitate implementation of MPC.

Intelligent building management systems aim to maintain thermal comfort and reduce energy consumption by learning occupant’s habits and behaviors. A component of these systems is dynamic scheduling, which ensures the HVAC system is only in use when the building is occupied. This paper develops dynamic schedules of building occupancy for an office building in London and estimate the effectiveness through a building simulation.

ASHRAE Guideline 36 aims to standardize a set of best practices for HVAC control. This paper compares a single-duct VAV terminal reheat strategy developed and implemented at Appalachian State University with the dual maximum strategy included in Guideline 36. The two strategies are similar but they differ in the details of implementation. The Appalachian State strategy controls the reheat valve with the zone temperature. Discharge air temperatures are monitored and when that temperature reaches 90 F, the VAV damper modulates to cap the discharge air temperature at the 90 F setpoint. Using numerical analysis and actual performance data, this study looks at the implications of this variation and compare operational outcomes with those established for the dual maximum strategy outlined in Guideline 36 and other energy conservation standards.

Small and medium sized commercial buildings, such as retail stores, restaurants and factories, often utilize multiple roof top units (RTUs) to provide cooling and heating for open spaces. A conventional control approach for these buildings relies on local feedback control, where each unit is cycled on and off using its own thermostat. Because a thermostat operates regardless of the overall building’s behavior, the conventional control approach could result in unnecessary energy use and high electrical peak demand via poor coordination among the units. The control solution is not site-specific and provides reduced energy consumption and peak demand with low sensor requirements. This paper provides recent results of long-term performance of the RTU Coordinator at field sites for small/medium commercial buildings.

The professional engineer has to focus on multiple aspects of a project including, safety, identifying operational and mechanical processes, specifications, control system design and construction, control system installation and system maintenance. How these parts are merged to satisfy the owner’s requirements and are conveyed from schematic design to construction and ultimately operated by the end-user is an interactive process. Integrating the right steps and checks in the process sets the basis for an effective and working design.

Early coordination with owner and engineer allows the controls integrator to understand the mechanical equipment design, owners’ capabilities and development of a “Controls Responsibility Matrix”. There are many ingredients for a successful controls system including coordinating other building trades, integrating with different protocols, installation quality and owner training expectations. The controls integrator will be a life partner with the owner, unlike the bricks and mortar type contractors, so specifying controls is a totally different concept. This presentation introduces the Controls Responsibility Matrix and the relationship for building a successful controls system.

Facts about the adoption rates for different technologies presented at almost every conference this century will be analyzed with the audience as well as their potential obstacles and solutions. Technologies: smart equipment, cloud optimization, automated diagnostics, total integration, performance predictive controls, occupant behavior prediction and self-learning controls.

The findings of a survey among Millennials exploring their slow adoption of new technologies is presented for discussion. Is the main obstacle lack of self-confidence, budgeted time or authority? Does YEA membership make a difference? Does the knowledge of successful stories remove concerns? Are Millennials too busy learning ductwork design to worry about controls? Is higher environmental conscience a strong enough driver in this group? Let's review together!

Until recently, the flagship standard on building energy performance – ASHRAE 90.1 – was silent on its application into these extremely hot climates. This presentation explores the new Climate Zone 0 and the recent changes to Standard 90.1 to expand its building performance guidance to these international locations. The presentation compares and contrasts critical building performance requirements for Climate Zone 0 with previous editions of the standard. It especially focuses on key building envelope and air leakage requirements that critically impact HVAC decisions and ultimate building energy performance. The session concludes with a discussion of additional areas where ASHRAE should expand its standards to address targeted building performance topics in CZ 0 and worldwide.

This presentation demonstrates the correct use of psychrometric calculations in the application of chilled beam systems for the conditioned space.

Having an understanding of how a chilled beam works is the first step to having a successful application. Fully appreciating how that chilled beam is applied and interacts with the rest of the heating and air conditioning system is the second step. All chilled beam projects are similar in design regardless of building type and allows for a quick review by the consultant. In a simple overview, we will review 7 basic steps to chilled beam application so that the start of your project is simplified and accurate.

This presentation focuses on successful installations of chilled beam systems. Correct psychrometric conditions, building pressurization and control sequences are highlighted.

In building design or research processes, building energy simulations are conducted using weather data. There are two types of the weather data for building energy simulations; one is the typical weather year (TWY) to estimate annual cooling/heating load and the other is the design weather data (DWD) to estimate maximum cooling/heating load. In this paper, we propose a new type of year weather data which can be used as both the reference weather year and design weather data, here called as the typical and design weather year (TDWY). The TDWY presented in this paper include each quantile values of multi-year observation data, which means that the TDWY is also used for the versatile design weather data. In this paper, we investigate more detailed property of the TDWY such as the simultaneity of each weather components.

Building dynamic simulation is a mature and advanced technique that has been used for decades to evaluate the thermal performance of building designs and existing buildings. Alternately, some researchers have developed reduced models that represent the thermodynamics of buildings using simple models based in real data. Lumped Parameter Models (LPMs), are lineal dynamic models that can be studied with the techniques developed in systems theory. This work identifies the LPMs that best represent 40 dwellings in the UK, and has applied system theory to study the response of those buildings in frequency to the driving forces of outside temperature, electricity and solar gains. The work has shown that the buildings present a response in frequency similar to low-pass filters with respect to outside temperature.

Temperatures in the Gulf Arab region exceed 50 Celsius during the summer, making cooling one of the biggest issues facing the region. This paper investigates the effect of wind speed, direction and temperature on the air-conditioning system thermal performance in an outdoor shopping and setting area. Moreover, two methods of conditioned air supplying will be tested using displacement diffusers and jet diffusers. The effect of different roof designs will be simulated. Some wind mitigation methods were tested like trees and perforated panels. A three dimensional Computational Fluid Dynamics (CFD) model was built to simulate the air flow and temperature patterns between the buildings. Mass and energy conservation equations were added to the model. K-Turbulence model was in the calculations. In order to validate the numerical model, wind-tunnel tests were carried out and compared with the air-flow patterns from simulations. Comparison between air flow simulations and wind-tunnel results yielded good agreement.

While small diameter (≤5 mm) tube-fin heat exchangers have the potential to improve
performance, successful designs must meet many criteria. Three case studies are presented
to illustrate how optimization techniques can be used to design drop-in 5mm tube-fin
condenser replacements for a domestic refrigerator, a packaged terminal air conditioner, and a window
air conditioner that meet engineering and economic objectives. An optimization method is
applied to heat exchanger simulation tools to evaluate the performance of heat exchanger
simulations to identify optimal configurations that meet many objectives. Results
indicate that these designs can significantly enhance energy-efficiency, reduce
refrigerant charge, and reduce material consumption and cost.

While the interconnections between the tubes of a heat exchanger can have a significant
effect on its performance, this circuitry is difficult to design by hand because of the
large number of possible designs and the nonlinear and discontinuous dependence of the
performance on that circuitry. We formulate the circuitry design as a binary constrained
optimization problem, and apply derivative-free optimization (DFO) algorithms. We apply a
number of existing DFO algorithms to this problem, and demonstrate that they can find
optimal or near-optimal circuitry designs for realistic coil sizes after a limited number
of simulations.

Developments in the Montreal Protocol include the development of a global consensus
to phase-down the use of HFC refrigerants, as well as the continuing transition among
developing countries to phase-out the use of HCFC and introduce HFC as potential
intermediary solution. This presentation covers efforts to develop optimized system designs
for mini-split AC units used in developing and high ambient countries using alternative
lower global warming potential refrigerants. There are available
candidate refrigerants that can be introduced during the current phase-out transition in
order to eliminate a costly 2-step transition from HCFC to HFC and HFC to lower GWP
solutions.

One approach for realizing the potential for both building energy cost savings and the
integration of renewable energy systems (RES) into the power grid involves the proactive
integration of building operation into the power grid by optimizing the operation of
energy sources with time-sensitive electricity price. The operation scheduling problem is
formulated with the RES, electrochemical batteries as energy sources, and the building
envelope as thermal energy storage, and is solved as a mixed integer programming problem.
A case study using the AMPL platform shows that such energy storage technologies provide
an effective way to connect energy supply resources and demands, and facilitate efficient
building operations.

Passenger comfort and ventilation efficiency in cars have attracted the attention of scientists and car manufacturers during the last years due to their potential of improving thermal passenger comfort, increasing efficiency and attended energy reduction. Nowadays, state of the art for the ventilation of passenger compartments of cars is mixing ventilation (MV) which is based on a high mixing degree of inflowing air with cabin air. In cooling cases, this is realized by high-momentum jets of cold air, which enter the cabin at the dashboard. Among the potential benefits of new developed ventilation concepts, are an increased thermal passenger comfort by reducing draughts and simultaneously energy saving potential by increasing the heat removing efficiency (HRE). The latter is of great importance especially for electrically powered cars to improve their range.

Improving comfortable environmental conditions for passengers has been the airlines’ interests in the recent decades. This paper discusses air distribution systems and factors affecting the goal of a healthy and comfortable environment for the passengers and cabin crew. Research was done by using ANSYS FLUENT 17.0 with new features. The standard air distribution systems used in recent air cabin are combined between mixing ventilation and personalized ventilation and this study makes a simple applicable modification on the ventilation system that improves the ventilation efficiency, thus protecting the passengers from being infected by each other. Commercial airplane environmental control systems (ECS) currently mix air ventilation systems, which are necessary to make a safe, thermally comfortable and healthy cabin environment.

A number of studies have shown that air distribution systems on the thermal comfort of occupants can vary depending on locations of diffusers and return outlets and types of ventilation systems. However, few studies have focused on air distribution strategies for serving multiple zones and their effects on local air quality and thermal comfort. Simulation results indicate that temperature distributions of two rooms were a strong function of ventilation type. However, indoor air quality of two rooms was significantly affected by both a ventilation type and an operation strategy. The results suggest that careful consideration is needed for designers and managers in selecting and operating air conditioning system to maximize the ventilation effectiveness and the thermal comfort in multiple zones.

Air-conditioning systems are often designed based on the model experiment and the numerical simulation. However, such study methods spend much time and costs in order to obtain the result. Therefore, the prediction method of indoor thermal environment with less time and cost is required. As for the practical use period, the air-conditioning system controls the supply air temperature and the airflow rate based on the feed-back control system which has temperature sensors. In this paper, Contribution Ratio of Indoor Climate (CRI) is employed to predict the distribution of the air temperature for the sake of the more efficient control system. The vehicle cabin and its air-conditioning system are focused because in-vehicle environment is a relatively severe condition compared with indoor environment of building. The purpose of this paper is to investigate the prediction accuracy of the air temperature in vehicle with CRI in order to clarify its applicability.

The buildings in which we live, work, and play have a tremendous impact on our health, wellbeing, and productivity. This presents a unique opportunity to utilize the design, construction, and operation of buildings to promote and improve human health. Numerous green building programs exist that focus on environmental impact and sustainability within the building design and construction industries, but there remains limited guidance on factors that impact the health and wellbeing of occupants. This is a serious gap, as occupants are the reason buildings are constructed, so their needs must be considered.

Relative humidity has a significant impact on indoor buildings and occupants. Specifically relative humidity impacts occupant health and comfort, as well as building energy usage and preservation. The ASHRAE Handbooks reference humidity over 300 times. Recent changes to the building envelope, HVAC equipment, and occupant requirements will impact ASHRAE humidity recommendations. There are many different HVAC product solutions that can be applied based on ASHRAE’s guidance. This seminar highlights some of the significant interactions concerning humidity levels, as well as outlining significant humidity recommendations and gaps.

Light, whether it originates from natural or electrical sources, is a formable stimulus for regulating circadian, hormonal, and behavioral systems. Over illumination may cause headaches, fatigue, medically defined stress, anxiety and decreases in sexual function. Under illumination may lead to chronic diseases such as breast & prostate cancers, obesity and early-onset diabetes. When considering standards for building design, it is therefore important to balance the desirable and undesirable impacts of light or darkness. Achieving this balance begins with an understanding of how photoreceptors in the eye function and why different visual and non-visual wavelengths of light cause different responses.

Indoor environments greatly impact human comfort, health, and productivity. To investigate and quantify this impact, a highly controllable and reconfigurable laboratory, the Well Living Lab, was designed and built to simulate real-world office and residential spaces. This presentation provides an overview of the experimental capabilities of the Well Living Lab, which include an integrated and scalable building control system, environmental and biometric sensing, and experiment management system. An overview of on-going and planned human-subject research is also provided.

This seminar introduces the experimental approach and selected test sites used to update the heat gains and diversity factors for different office equipment in the ASHRAE Fundamentals handbook tables. The seminar gives an overview on the data logger’s selection criteria for measurement and calibration purposes as well as the testing duration for different equipment. An overview of the experimental results for both, heat gains and diversity factors is also given. Transient data is shown and some typical and atypical findings are pointed out.

This seminar gives an overview of methods used for the determination of recommended heat gains and diversity factors for different office equipment in the ASHRAE Fundamentals Handbook tables. In particular, the effects of a number of tested pieces of equipment as well as the interval duration for data reduction are investigated. Analysis on the effect of the different number of tested pieces of equipment and averaging interval on the diversity factor is also discussed. Recommendations for minimum equipment count for determining diversity factors as well as recommendations for future work are given.

Commercial kitchens and dishrooms house equipment that generate the most intensive concentrations of sensible and latent loads. This seminar presents the heat gain findings from RP1631 Countertop Commercial Appliance Emissions along with the updates to the appliance heat gain tables in the handbook.

Building operations are a significant consumer of energy and contributor to carbon emissions in the U.S. and around the globe. Energy audits offer significant potential in reducing building energy use by providing tailored recommendations involving equipment upgrades, operational adjustments and building recommissioning. However, energy audits are a time intensive process that requires significant experience and training. This causes high costs related to performing an audit and prevents many businesses from having an audit completed. Automating the audit process will not only reduce the cost of audits, but clients will be provided with more repeatable and accurate recommendations based on improved data collection and analysis. Previous work and the current state of the art of robotic auditing tools are discussed in this paper, followed by open challenges and future possibilities of autonomous vehicles for conducting audits.

A building owner can use a realistic energy model to understand the future building’s energy performance. But what happens when the design energy model predicted energy use and the utility bills have a significant variance? Can adjusting the energy model to match the utility bill, or calibrating it, successfully identify the cause of the variance? Will this show strategies to bring the actual energy use back in line with the predicted energy use? This paper reviews the calibration effort of a Medical Office Building where the actual energy use was significantly above the predicted energy use.

How energy efficient can commercial and multifamily buildings become in the near future if first cost is not considered? The paper describes how building energy simulation modeling was used to try to answer this question. The first step was to assemble a list of energy efficiency measures that can be included in the design of non-residential buildings. The list included both commonly used and cutting edge energy efficiency measures with the goal of being comprehensive, at least for measures that can be modeled. Input was sought from many people to ensure that the list of measures did not exclude any important ones.

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Making an informed, responsible ethical decision is not as easy as it may seem. This workshop provides tools to enhance your ability to frame engineering and business dilemmas in accordance with ethical principles in order to make the critical and informed decisions in the workplace. You'll learn how to apply an ethical framework to future decision-making – using a model that you can put into practice right away. You'll have a better understanding of ethical challenges, how to analyze them while considering implications for any stakeholders, and how to choose the right course of action based on ethical principles.

This is an interactive session where participants hear about an ethical violation, then break up into small groups and discuss the ethics case adjudicated by the NSPE. Test your ethics IQ against an actual case decided by a board of your peers and obtain ethics continuing education credits in the process. Three cases are presented along with the final outcome.

This is an interactive session where participants hear about an ethical violation, then break up into small groups and discuss the ethics case adjudicated by the NSPE. Test your ethics IQ against an actual case decided by a board of your peers and obtain ethics continuing education credits in the process. Three cases are presented along with the final outcome.

In California there are 70 non-residential and apartment house ZNE projects in 2015, whereas there are 21 ZNE projects in Japan in 2015. Hence, it’s supposed to be a good example for ZNE dissemination in Japan to clarify the problems toward ZNE dissemination in California. This paper addresses the energy performance of a ZNE office building in Northern California from the perspectives of simulation, measurement, verification, and code compliance. Simulations of the building’s energy use were undertaken during the design stage to demonstrate code compliance and measurements of actual energy use were taken for six months after occupancy.

Occupancy plays a significant role in the amount of energy used in buildings and their presence is stochastic in nature. There is extensive evidence to suggest that buildings usually do not perform as well as predicted by energy simulation. Use of unrealistic occupancy data as an input of building energy modelling (BEM) is a major reason behind it. As a result, large discrepancies are being observed between predicted and actual energy performance, typically averaging around 30% and reaching as high as 100% in some cases. This paper covers research that aims to develop an occupancy prediction model using Artificial Neural Network (ANN) for improving the accuracy of building energy simulation.

The increase in the electricity bills and the new opportunities to participate in the electricity market has encouraged companies with activities not related to the energy industry to engage and actively participate in the electricity market to reduce costs and become more competitive. With the overarching goal of making cost-effective investments and decarbonizing their operation, the first step to improve these companies’ bottom line is to comprehend their electricity costs. This paper focuses on detailing a methodology to model electricity commercial bills and generate real-time price curves; thus allowing customers to calculate their half-hourly true cost of electricity and to assess the challenges of reaching net zero energy buildings for different UK regions and connection voltage levels, across every month up to the financial year 2019-20.

An accurate building energy forecasting model is the key for real-time control of advanced building energy system and building-to-grid integration. Feature selection, the process of selecting a subset of relevant features, is an essential procedure in data-driven modeling due to its ability to reduce model complexity, increase model interpretability, and enhance model generalization. In building energy modeling research, features are often selected purely based on domain knowledge. There lacks a comprehensive methodology to guide the feature selection process when developing building energy forecasting models. In this research, a systematic feature selection procedure for developing building energy forecasting models is proposed in consideration of statistical data analysis, building physics and engineering practices. The procedure includes three main steps: (Step 1) rule-based feature pre-selection process based on domain knowledge. (Step 2) feature removal process through filter methods to remove irrelevant and redundant variables. And (Step 3) Using wrapper method to obtain the best combinations of features. A case study is presented here using simulated building energy data that are generated from a medium sized commercial building (a DOE reference building). In this study, the energy forecasting model generated by using the proposed systematic feature selection process is compared with other models such as a model that uses conventional inputs, and a model with single feature selection technique. The comparison result shows that, in terms of cross validation error, the model with systematic feature selection process shows much better model performance than other models including that with conventional inputs and that uses only single feature selection technique.

Environmentally-friendly heat pumps operate using reversible adsorption and desorption of hydrogen from metallic compounds, which were incorporated in a cycle having a work input (compressor) or thermal energy input (generator). Some challenges faced by compressor-driven metal hydride heat pumps are poor heat transfer in the metal hydride beds and high compressor discharge temperatures. To overcome these challenges, a metal-hydride slurry in conjunction with various isothermal compression techniques were used. Liquid-flooded, electrochemical and liquid piston compressors were modeled and integrated into a system model in order to assess their impact on the performance of the slurry-based metal hydride heat pump system.

This paper presents the design of elastocaloric cooling system driven by hydraulic actuators. Ni-Ti tubes under axial compressive loading mode are used to provide cooling and heating. Those Ni-Ti tubes are enclosed in four identical beds, which are driven by two one-way hydraulic cylinders. Operated under the single-stage reverse Brayton cycle, the system achieves heat transfer and heat recovery by using a heat transfer fluid network controlled by solenoid valves. System coefficient of performance of 11.0 and temperature lift of 24.6 K are estimated based on a dynamic model developed in our previous study.

This presentation covers an investigation into the design and preliminary results of a room temperature magnetic refrigeration prototype and describes the physical prototype along with its operational and measurement envelopes. General design goals included: A wide range of cycle parameter control, independent fluid and magnetic circuits, extensive measurement capability and compact design. The maximum no-load span recorded was 21 K and the maximum power recorded was 26 W at a span of 1 K. Three cyclical parameters were varied to help determine the optimal cycle for such a machine.

Under ASHRAE Research Project 1699 (RP-1699) we provide an update of the data used both in the “Climatic Design Information” chapter of the 2017 ASHRAE Handbook of Fundamentals and in ANSI/ASHRAE Standard 169, “Weather Data for Building Design Standards”. A total of 8118 stations were successfully processed worldwide representing a 26% increase compared to 2013. Reported elements now include monthly average wind speed, wet bulb temperature return periods and monthly-average daily all-sky global horizontal solar radiation. A number of pre-screening and post-processing tools were developed in order to ensure a reliable and useful product.

Air-leakage through building envelopes causes significant energy losses. Air-tightness codes do not account for air-leakage due to wind-driven pressure gradients and thermal resistance codes do not consider any air-leakage effects. Air-leakage needs to be included codes to understand the effects on thermal performance. We calculated effective thermal resistances in 103 locations considering air-leakage effects, to see effects on thermal performance. Simulations showed decreased thermal resistances and increased energy losses in every climate. Varying levels of thermal performance demonstrate relative importance of air-tightness in different climates. Results imply current codes do not accurately represent thermal performance and where air-tightness matters most.

This paper describes two of the unique elements of the advanced control sequences developed for ASHRAE Research Project 1455 (RP-1455): automatic fault detection and diagnostics (AFDD) and hierarchical alarm suppression. AFDD is a method used to identify fault conditions and provide possible diagnoses. Hierarchical fault suppression is a method based on hierarchical structure used to reduce the incidence of nuisance alarms. It is written by the members of the research team and is part of the deliverables for this research project. AFDD and hierarchical alarm suppression will further enhance the ability of DDC systems to make intelligent alarm distribution and management decisions.

This presentation discusses fundamental thermodynamic concepts as well as experimental investigations of elastocaloric cooling processes and presents a concept of a potential elastocaloric air conditioning device. Various cooling cycles suitable for elastocaloric cooling are introduced and the process efficiencies are determined based on a graphical approach. The graphical method is validated experimentally with a specially designed scientific test setup, which enables the measurement of mechanical and thermal process quantities under various thermal boundary conditions. The results are compared with the values predicted by the graphical approach. Furthermore, a concept of a continuously operating elastocaloric air cooling device is introduced.

Active magnetic regeneration is one of the most promising alternative technologies for the development of heat pumps and cooling systems for applications near room temperature. Recently, numerous papers have reported on the development of magnetocaloric materials, magnetic circuits, prototypes and cycle optimization. This presentation examines some of the main challenges encountered in the current state of the art technology. It provides an overview of how design choices impact cooling power and work requirements from a system engineering perspective.

One of the most important relationships in the commissioning process is between the commissioning agent, the owner and the engineer of record (EOR). A relationship that requires ongoing coordination with common goals defined from the beginning of the project. But what happens during Design-Build projects when the relationship between the EOR and contractors may result in different goals and can cause a conflict of interest? This paper provides a resource for all commissioning agents participating in a design-build project and offers guidelines to use to navigate from design to construction and to occupancy as effectively as possible.

This paper addresses issues from DGNB refurbishment and explores how a design process can be streamlined to address refurbishment and still preserve the gains from IED. Registration of the existing conditions is a prerequisite for a good design process where the software tools developed to ensure low energy consumption and good indoor climate can be used, and 3D scanning is therefore making a new and important contribution. The paper includes case studies of both ideal and applied design processes from an architectural office that specializes in sustainable projects.

Automated fault detection and diagnosis (AFDD) methods, followed by corrections, have the potential to greatly improve a building and its system’s performances. Existing AFDD studies mostly focus on component and sub-system AFDD. Much less effort has been spent on detecting and diagnosing faults that have a whole building impact. In this paper, an integrated data driven method: Pattern Matching Principle Component Analysis method, is developed and applied for whole building fault detection. Real building data that contains artificially injected faults and naturally occurred faults are used to evaluate the method’s accuracy and false alarm rate. The method presents great potential to be a cost-effective and accurate whole building fault detection strategy.

This paper explores opportunities for, and impacts of potential regulated energy performance and emission reduction standards for existing buildings in British Columbia. It includes evaluation of four standards – Standard 100-2015, Standard 90.1-2010 (BC Building Code), National Energy Code of Canada for Buildings-2015 and retro-commissioning procedures. Standards are applied to the existing building stock, except low-rise residential buildings, at the time of existing building alterations or repairs that trigger the BC Building Code or Vancouver Building Bylaw.

Thermal comfort quality impacts health care workers’ outcomes and patients’ well-being. However, unlike any other type of indoor environments there is often a great variability in activity levels and health condition among occupants in a health care space that makes it difficult to achieve acceptable conditions for certain groups of occupants without sacrificing other groups. This seminar examines types of wearable sensors, their requirements and mappings in assessing individual thermal comfort and how such individual comfort data can be used to drive the operation of personalized and room indoor climate systems in real-time.

Occupants interact with thermal control devices available in buildings to address their comfort needs/desire; hence, the resulting behavior is an expression of one’s thermal preference. The new generation Personal Comfort System(PCS) with wireless connectivity offers a continuous stream of individuals’ heating and cooling usage data along with occupancy and environmental measurements in real time. This presentation summarizes findings from a field study of 40PCS heated and cooled chairs in an office building and reports the predictive performance of personal comfort models developed from continuous PCS data. Proposed models show an improvement of individuals’ comfort predictions by 20-30% compared to PMV.

Since the human body is governed by the thermoregulation principle to balance the heat flux between the ambient thermal condition and the body itself, skin temperature has a significant role in maintaining the physiological principle. Therefore, the author investigated the potential use of skin temperature and its technical parameters to establish a thermal sensation. This seminar discusses optimally combined skin temperature information collected from selected body areas, and examines how much reliable and applicable the designated skin temperatures are for estimating individual thermal sensations.

In this case study, CFD was used to evaluate roof modifications of an aluminum foundry. The study shows the strategies used to provide an efficient and effective computational model that will provide the key data needed to evaluate the large space and make the right modifications to maintain air temperature limits. The modeler’s understanding of fluid dynamics will be a critical element towards applying appropriate strategies in the development of the CFD model to provide a robust design evaluation tool. Care must be taken in specification of the inputs to a CFD model, and interpretation of results and associated implications.

Natural ventilation is characterized by low driving pressures leading to the need for large ventilation openings. In addition, natural ventilation systems must remove sufficient heat to ensure thermally comfortable conditions. This is particularly challenging in high heat gain spaces such as raked-seat auditoria where heat gains can be as high as 90W/m2. This presentation talks through the design and CFD modeling of a 500-seat theatre in the UK which harnesses buoyancy-driven displacement ventilation to deliver a comfortable and ‘atmospheric’ performance space. Two modeling techniques are used: traditional Reynolds Averaged Navier Stokes and Large Eddy Simulation.

Displacement ventilation (DV) has a become a commonly used system in a broad range of applications due to its energy saving potential and superior indoor air quality. There are various rules of thumb that dictate the maximum cooling load that the system can handle. Although using the system for higher cooling loads is not recommended, there are cases where it is still advantageous to do so. This seminar explores the performance of a DV system outside of its normal operating range using CFD. Design guidance will be provided and application-specific trade-offs will be explored.

Natural ventilation is an efficient way of removing high internal heat gains for buildings and its energy saving potentials however depend on many parameters. This presentation reports a series of GIS maps for natural ventilation potentials of North America, similar to the well-known solar potential maps. These maps provide key graphical information of energy saving potentials of both single sided and cross natural ventilation in terms of total hours suitable for natural ventilation and associated energy savings for over 50 cities in the US and 10 cites in Canada.

The current diffuser selection guide described in ASHRAE handbook-fundamentals provides the correlation between diffuser characteristics, such as throw length and types, and its performance to distribute supply air and thereby to optimize space air diffusion. However, the current guideline considers only five diffuser types and the range of sensible cooling loads that is up to four times larger than those we find in today’s energy efferent buildings. This presentation shows the updated ADPI-based guideline that includes 15 diffuser types at lower cooling loads, typical for today’s buildings. The new guideline shows the minimum airflow set-point for a VAV systems.

The performance of air distribution using overhead mixing diffusers is evaluated using ADPI. The ADPI methods is often used for selection of diffusers used for both cooling and heating. However, the current diffuser selection guide confines the application to only cooling mode. This presentation introduces a new ADPI for heating mode and specify the criteria of diffuser selection from the perspectives fluid dynamics and occupant thermal comfort based on ASHRAE Standard-55. The presentation covers the development of the effective draft temperature for heating applications and the resulting ADPIs curves with various diffuser types.

This presentation provides fundamental design data that supports optimal diffuser selection in mixing ventilation with heating and cooling operation. It shows how diffuser adjustment, room-supply air temperature differences and return air grille location impact ADPI and E_V. The study points out connections between ADPI and E_V and shows similarities and differences for heating and cooling operation. It presents the operation characteristic that provide good E_V while maintaining acceptable ADPI. Also, it shows how diffuser adjustment may improve E_V. Furthermore, the presentation shows the cases where return air location may have a significant effect on ADPI and E_V.

The effective draft temperature was experimentally developed in 1949 in Sweden. This is the current equation used to calculate ADPI for cooling. In 1972 Nevins and Miller presented an ASHRAE paper which determined that boundaries for ADPI to obtain a 70% occupant comfort level. After 33 years, this method needed many updates as buildings and air distribution systems changed. The ASHRAE RP 1546 updated and confirmed the ADPI predicted comfort levels using Standard 55. It produced the effective draft temperature equation for heating. Furthermore, it developed ADPI values that can predict thermal mixing in heating.

As cars are parked within an underground parking structure, CO and other exhaust fumes are emitted into the atmosphere. There is a need for an efficient ventilation system that can remove these toxins, circulate fresh air into the garage, and assist fire fighters in the case of a fire emergency. There are two options for this task: ducted or ductless ventilation.

Ducted ventilation is heavily used in the US and other global markets. While this has been the standard for many years, innovations in the field of ventilation have shifted the conventional ventilation system towards ductless designs.

An analytical study is carried out to assess the impact of corrections to nominal test conditions on the measured energy factor for residential water heaters. While test conditions are specified in the method of test, the difficulty in exactly achieving these test conditions in the laboratory necessitates a computational approach to correct the results to nominal conditions. This paper examines the magnitude of those corrections for a range of water heaters of various fuel type, heating method, and size across a number of potential draw volumes during a 24 hour simulated use test.

The impact of the high power requirements of large residential tankless electric resistance water heaters on electric system distribution wiring, transformers, breakers, and other equipment is an area of concern for both electric utilities and builders. This study analyzes how probable and worst case diversified electrical demand of large (28 kW) residential tankless electric water heaters compares to that of 4.5 kW storage water heaters in residential applications as a function of number of households on a given electrical distribution circuit.

Information on hotel hot water use patterns has been limited until now, resulting in most hotel hot water systems being designed using extremely old hot water use data (45-80 years old) that predate the introduction of water and energy efficient fixtures and appliances. In recognition of this fact, ASHRAE funded research project 1544 “Establishing Benchmark Levels and Patterns of Commercial Hot Water Use – Hotels” to both develop a monitoring methodology that could be duplicated by others to collect hot water use data from a larger number of hotels and to obtain updated hot water use information from at least two hotels. This paper compares hot water use results collected for a “travel” hotel which had neither meeting rooms nor food service and a “business” hotel which had both.

This is the fifth paper in a series of technical papers written to describe results of ASHRAE research project 1544. This paper builds on information presented in the project final report, the three previously published papers to present information on using the updated data to select water heating systems for hotels of any desired size and compares results of this sizing method to other hotel hot water system sizing methods described in the ASHRAE Service Water Heating Handbook Chapter through the use of examples.

The outdoor wind and air flow around buildings affect the indoors in several ways. Wind is the primary driver for natural ventilation by exerting pressures (both positive pressure and negative suction) on building surfaces. Wind also can cause building exhausts to migrate outdoors to nearby air intakes and pedestrian locations, creating poor air quality indoors. This presentation focuses on approach wind conditions, the air flow patterns around buildings and wind pressures exerted on buildings. These effects are the fundamental starting place for more detailed ventilation and air quality analyses. Also discussed are modeling methods using CFD and wind tunnel similarity.

There are four types of dispersion models; graphical, analytical, computational and physical. Each one of these models has its appropriate applications, but misapplying a model can result in either an inadequate exhaust design or in an excessive effort (i.e., fees). Therefore, this presentation provides the audience with guidelines on how and when each of these models should be utilized, what the limitations are of each model, and some insight in how to determine if models are being properly utilized.

Laboratory exhaust systems are a central element of high performance science and technology facilities. Air quality, energy efficiency, and operational reliability are deeply impacted by the performance and design of the laboratory exhaust system. This presentation focuses on the design process, considerations, fan basics and control of high performance lab exhaust systems. Brief design application examples will be included to connect fundamentals with practice. The objectives of this presentation are to provide guidance on design team collaboration, insights on lab exhaust design fundamentals and share examples of application.

This paper describes experimental results obtained from running a household dehumidifier overnight and comparing the temperature and humidity changes before and after turning on the dehumidifier, and comparing these changes to the amount of energy used to run the dehumidifier. This work is being performed in response to sustainability goals proposed by the United Nations call for “off-the-shelf” sustainable technologies in third world nations. The objective is to test the energy-saving qualities of dehumidifiers as a method of home heating. The data reduction of the household humidifier first calculates the amount of energy in the form of heat that is generated by the dehumidifier by comparing the change in temperature, time, kWh, and humidity, and applying these changes to the equation for the change in enthalpy in atmospheric air.

This paper presents a new, interior-space, environmental conditioning strategy, referred to as spatially adaptive heating, ventilating, and air conditioning (HVAC), where supply air locations within a room are repositioned in response to changing thermal loads or other room conditions. In order to quantitatively examine the technical merits of this concept, a computational fluid dynamics (CFD) model of a typical office was created using SOLIDWORKS Flow Simulation software and benchmarked using full-scale, experimental, velocity and temperature data from the literature. In light of promising results, a one-fifth scale model office was constructed to examine additional scenarios not covered experimentally in the literature and to validate computer simulations of these scenarios. Initial results from the scale model tests are described, and preliminary engineering concepts for achieving supply register relocation are presented. In addition, the opportunities, challenges, limitations, and potential for energy savings associated with this new strategy are discussed.

Radiant systems are increasingly being used for heating and cooling spaces due to its benefits like better energy efficiency, improved thermal comfort and IAQ. In addition, the radiant systems reduce the ductwork and are aesthetically pleasing. However, the effectiveness of radiant systems for optimal design need detailed study of impact of several parameters. In this paper, detailed CFD simulation of a typical room with radiant panel for cooling has been performed. Typical heat loads from human, lights and computer are considered in the model. Different scenarios of return diffuser location, on floor and on ceiling, are considered. Impact of radiation and buoyancy are modeled in the simulation and typical thermal boundaries are applied for walls, roof and floor. The detailed temperature and flow distribution obtained from simulation are used to evaluate and optimize the cooling system, supply flow requirements and diffuser locations.

This presentation examines measurements of energy and water losses in a residential hot water distribution system using a PEX home-run manifold.

This seminar presents the results of pressure drop testing of pipe, with and without fittings and compares these results to the numbers found in standard engineering reference manuals. A selection of copper, CPVC and PEX piping from 1/4 - 3/4 inch nominal and commonly available elbows at velocities from 1-12 gpm have been tested. The method of tests and the results are presented. Come learn whether these are higher or lower and discuss the implications of not having good numbers for the future of safe, efficient and high performance plumbing design.

Mechanical ventilation accounts for a significant portion of the total energy consumption in large office buildings. The air needs to be transported over large distances through ducts, it requires filtration and needs heating and cooling to condition the ventilated space. Most offices in North America have closed windows, and manually opening these windows for natural airflow is discouraged as this can interfere with the operation of the building’s HVAC system. The recent drive for energy efficiency has created renewed interest in using natural ventilation to reduce energy consumption. This paper suggests a new approach to natural ventilation by using motorized windows controlled by the Building Automation System (BAS) in existing buildings. This paper presents a detailed breakdown and analysis of the simulation results, including an economic feasibility analysis of the application of BAS-controlled motorized windows.

The purpose of this research is to elucidate the influence of overhang of an exhaust hood on the capture and containment of the exhaust hood. The capture and containment performance depends on capturing and containing the thermal plume from cooking appliances. Larger exhaust hood openings seem more able to capture thermal plumes even if they expand due to air disturbance. However, provided that the ventilation rate is the same, the face velocity of exhaust hoods is low of the larger exhaust hood openings. This may prevent containment of the thermal plume from cooking appliances. We prepared an electric fryer and an electric noodle cooker. These devices are typical cooking appliances whose thermal plumes are weak and strong, respectively. The capture efficiencies of exhaust hoods were revealed, including the parameters of overhang length of exhaust hood and ventilation rate.

The K-12 education system is the largest public enterprise in the United States. Public K-12 schools employ approximately three million staff and enroll more than fifty million students. Public schools have an expenditure that includes funds for salaries, benefits, transportation, materials and energy use. Of these expenditures, energy use is often targeted for reduction, which sometimes results in reduced ventilation. While saving energy is desirable, it must be achieved without compromising student health. Lack of proper ventilation can result in a decrease of students’ attention and can cause health-related issues. This paper evaluates how the type of heating, ventilation, and air conditioning (HVAC) systems installed in schools and HVAC operation conditions affect temporal and spatial distributions of carbon dioxide (CO₂) concentration in classrooms.

This paper discusses a systematic experimental study of the effects of operating conditions (i.e. relative humidity and temperature of working air streams) on the transport of water vapor and CO2 (as a major indoor air contaminant) through a series of standard polymeric materials suitable for membrane media used in ERVs’. Results are reported for the permeation experiments of binary mixtures of water vapor and CO2 in five commercial polymers of two major types (glassy and rubber). The selectivity of water vapor over CO2 was also evaluated from permeation experiments. In general, the permeability results suggest that ERV exchangers using polymer membranes can achieve high latent effectiveness (i.e. very high water vapor permeability) over a wide range of operating temperature and relative humidity while maintaining very low CO2 permeability and very low EATR crossover rates (<1%) accordingly.

This presentation focuses on the use of computational fluid dynamics (CFD) modeling to predict the performance of an air distribution system inside the built environment. The presentation provides an introduction to CFD and how it can be used effectively to study thermal comfort and indoor air quality. A broad range of examples will demonstrate how CFD can be used to tackle common design challenges in the indoor environment including thermal comfort optimization, enhancement of indoor air quality and air volume reduction, all with the aim of reducing the size and energy usage of the air distribution systems.

Chilled beam systems have been used in Europe for many years, but they've only started to be used recently in the United States. In this study, the effect of the active chilled beam systems on flow and temperature distribution in a typical room with occupants has been investigated using CFD. This presentation explains how a detailed three-dimensional analysis helped find an optimum throw angle for mixed supply air ensuring the thermal comfort level and reducing draft risk in the room.

CFD is commonly used for data center design and operational planning. It provides confidence in routine and innovative designs and enables change in a risk averse operational environment. Yet still more do not take advantage of this technology. One barrier is that accurate prediction for an operational data center requires detailed models. In contrast the designer often doesn’t know what the IT configuration will be. So will garbage in be garbage out? This seminar uses simplified studies to show that sensitivity analysis enables the designer to identify efficient and effective designs perform well despite the uncertainties in IT load/configuration.

In today’s environment volume servers are commonly designed for specific workload types. As a result, in the updated edition of the ASHRAE Datacom Equipment Power Trends and Cooling Applications publication, volume servers and their corresponding power trends are segregated into eight unique workload types. This is a significant change from the 2^nd edition which delineated the power trends only by server size and the number of sockets. In addition, servers are no longer one size and one configuration fits all. These purpose-built servers include specific features and components sized to meet a customer’s workload requirements.

Volume servers are becoming aligned to specific workload types and server configurations to meet customers’ needs. This translates to an increase in server configurations and potentially significantly different power ranges and power trend trajectories even in the same server size. The distinction of servers by workload type and size provides greater accuracy in projecting the power ranges and trends as compared to server size and number of sockets as in the 2^nd Edition of the ASHRAE Datacom Equipment Power Trends. This session discusses the updated power trends over the next decade as a function of eight unique workload types.

The increasing volume server power trends are making it increasing difficult to properly plan for future space, power and cooling needs in the data. This seminar provides assets to help facility planners better understand how to properly apply the updated ASHRAE Datacom Equipment Power Trends and Cooling Applications data. It discusses trends in airflow requirements and how these relate to the data center capabilities for both air and liquid cooling. Examples of how to use these updated guidelines are presented.

A case study in a test house was conducted to investigate the fate and transport of benzyl butyl phthalate (BBzP) and di-2-ethylhexyl phthalate (DEHP) in residential indoor environments and the influence of temperature. Total airborne concentrations of phthalates were sensitive to indoor temperatures, and their steady-state concentration levels increased by a factor of three with an increase in temperature from 21 to 30 ºC. Strong sorption of phthalates was observed on interior surfaces, including dust, dish plates, windows, mirrors, fabric cloth and wood.

Filtration and ventilation are commonly used to remove or dilute airborne contaminants and improve indoor air quality. This presentation concentrates on the effectiveness of residential HVAC filters for reducing air contaminants in residential buildings. To assess the efficacy of residential HVAC filters, efficiencies and pressure drops of filters of different MERV levels were first measured according to ASHRAE 52.2. Then an indoor air quality (IAQ) model was applied to characterize health-relevant indoor aerosols in different residences with various combinations of filter types and ventilation conditions. Modeling results are discussed in the presentation.

Indoor air pollution is an environmental health risk. The methods of reducing concentration of indoor contaminants vary, depending on the design of the air cleaning device, its location and on the contaminant phase. Air cleaning devices can be categorized by the type of contaminant that they remove, particulate and gas phase. This presentation covers recent studies of various filtration methods and their effectiveness in removal of particulate and gas phase pollutants. Test methods used to assess the performance of air cleaning devices are presented and their applicability to various contaminants is discussed.

This workshop discusses the results of 1627-RP, completed in 2016. This research investigated the effectiveness of 30% Advanced Energy Design Guidelines (AEDGs) for K-12 schools and small office buildings, determined the factors common to well and poorly performing buildings and provided recommendations for how future AEDGs could be made more effective.

Using the recent success of 1627-RP as a template, this workshop discusses the potential for additional research projects that identify statistically-significant samples of real buildings built using Std 90.1-2010. Can this type of research be replicated to provide real-world input to future ASHRAE Standards and publications? What guidance can the actual performance of these buildings provide?

This paper examines developing air conditioning systems in the playground zone of a stadium by employing several kinds of technologies to cool the outdoor spaces. The most serious challenge of air conditioning in a playground zone in stadium is controlling the temperature and humidity in the outdoor area and also the enormous energy needed by the cooling system to maintain thermal comfort conditions within the football playground area. The main task for the analyzed model was to ensure the better method to distribute air to achieve the human comfort level for players and reducing the cooling capacity of playground zone by using a large sunshade to reduce the sun's rays and maintain the stadium's temperature.

This paper describes the chiller selection design and procurement process for a building thermal management system. The design procedures described in this paper are based on those carried out during an energy efficiency engineering internship in a local Los Angeles company and thus serving as an example of real world training. This paper presents the results of a case study to replace chillers that are approaching the end of their useful life. This case study is an example of how engineering interns are exposed to the various ASHRAE Standards. The retrofit project was carried out according to specifications and drawing of the existing obsolete equipment and adhering to Standard 90.1 “Minimum Requirements for Chillers” and the ASHRAE “Chiller Life Expectancy” guidelines used to govern chiller selection and installation. Results for COP lift versus load and chiller load versus system load are presented in the paper.

Louvers (or vents) are primarily used in air conditioners, fans and air-coolers for directional circulation of air in a confinement. Hence, it is of interest to determine the downstream flow field characteristics of air passing through these louvers for cooling and ventilating the confinement. A detailed Computational Fluid Dynamics analysis can be done by resolving all the geometrical features of the louver and setting the appropriate boundary conditions. However, this involves high computational effort, especially, in case of physical movement of the louvers for time-varying directional delivery of the air. The central aim of this research is to develop a rapid airflow model which can replicate similar downstream flow characteristics while obviating the necessity to geometrically resolve the louver. This paper examines the results of this research.

Air finned-tube evaporators and/or condensers, are the predominant type of heat exchangers used in building air conditioning applications. The compact V-shaped, or sometimes called A–shaped, finned-tube heat exchanger installation considerably enhance the capacity of heat transfer by allowing the maximum number of coils installed in a given space and increasing the total surface area of heat transfer. On the other hand, this design configuration creates noticeable problems of uneven distribution of air flow velocity over the heat exchanger surfaces, which decreases the energy efficiency of the air conditioning system. This paper uses computational methods to investigate the problems of mismatch between the air and refrigerant flow distributions and propose different engineering solutions at air flow side as well as refrigerant flow side to remedy the problems.

Streamwise longitudinal vortex generation is a promising method for enhancing air-side heat transfer performance of heat exchangers in a range of applications. In this paper, the vortex-enhanced air-side flow and heat transfer for offset strip-fin array is studied with an emphasis on understanding the relation between flow structure and heat transfer. The flow and heat transfer behavior of the baseline offset strip-fin geometry has been thoroughly investigated both experimentally and numerically in the literature. However, numerical modelling of vortex generator (VG) enhanced offset-strip fin array has not been reported. The predictive capability of the model in terms of the local flow and heat transfer characteristics is evaluated in such geometry for both baseline and enhanced cases.

Currently, the taxonomy of HVAC system and components has various basis, which can get quite complex because of the various components and system configurations. In addition, some of the system names might be commonly used in a confusing manner, such as “unitary system” vs. “packaged system.” Without a systematic classification, these components and system terminology can be confusing to understand or differentiate from each other, and it creates ambiguity in communication, interpretation, and documentation. It is valuable to organize and classify HVAC systems and components so that they can be easily understood and used in a consistent manner. This paper aims to develop a systematic classification of HVAC systems and components.

Within the last decades, needs for building control systems that reduce cost, energy, peak demand and that facilitate building-grid integration, district-energy system optimization and occupant interaction have come about. Model Predictive Control (MPC) is a control technique that utilizes system models and forecasts to predict performance and optimize control inputs in real-time. This presentation discusses in detail the ways occupant interaction with MPC-controlled building systems can occur, particularly as related to the control of HVAC systems, including benefits, drawbacks and challenges. This presentation discusses progress on current work that is exploring and implementing these interactions in demonstration buildings.

This presentation reviews current occupancy behavior (OB) based MPC control projects for smart building at the University of Texas at San Antonio. Challenges and opportunities of OB-MPC for smart buildings are presented and discussed, particularly on models to use, occupancy data and optimization algorithms. Simulation results show that OB-MPC can achieve up to 24% energy cost reduction in residential buildings and 17% in commercial buildings.

This presentation covers the collaborative research work from cross-functional team effort behind the journal paper that was recently honored with ASHRAE Research Journal Best Paper of the Year Award. The development and application of a fault and occupant tolerant control technology, its online implementation, and results from several tests conducted for a large-sized HVAC system are discussed. The performance and limitations of the fault detection and diagnosis, model predictive control as well as the fault and occupant tolerant control algorithms are illustrated and discussed using measurement data recorded from multiple field tests.

MPC is a new approach to controlling building systems to optimize equipment operation. Meanwhile, occupant behavior is a key contributor to the uncertainty of energy consumption. The combination of MPC and OB would foster great building energy saving potential. The integrated network to measure occupancy and behavior related with environmental parameters is introduced. With the measured data, the occupant behavior predicting models will be built and integrated with the building system model to improve the control logic. A demonstration of the predictive model application is presented to see the effect of occupant behavior based model predictive control.

This presentation introduces exotic applications of absorption heat pumps that have been actually implemented. These can serve to provide new creative solutions to modern challenges in industrial thermal management. After a quick introduction into absorption process, the examples are explained in their economic context, the technical solution is explained in brief and the results are explained in their economic and environmental context.

This presentation introduces numerous case studies from the US and beyond for successful applications of absorption heat pumps. A diverse set of examples is presented, and all are demonstrating real world savings of energy and water.

This presentation provides an overview of which mass markets have potential for large-scale adoption of packaged absorption machines. Whereas small scale cooling applications often struggle to compete on energy savings with electric-driven cooling, heating applications often have compelling energy and economic attributes. Small packaged units are beginning to be available to serve these applications.

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Presentation content includes items that engineers need to be aware of so that obstacles to a successfully operating system can be avoided. UFAD systems are highly integrated with other services and more closely couple with the building structure than compared to traditional overhead mixing systems. This inherent characteristic of UFAD systems demands an integrated and collaborative approach when working on these types of projects. This seminar addresses issues that need attention and sometimes get overlooked when designers treat UFAD projects similar to overhead mixing system during design.

The major challenge for design of underfloor air distribution systems is the reconciliation of comfort requirements between the interior and perimeter zones served by the system. For a variety of reasons, the past UFAD design strategy has proved less effective. Newer strategies have been proposed and applied to overcome this issue. Each of these strategies has implications for the building architecture, first cost and performance for specific weather conditions. Some strategies may even be used together. This presentation reviews each of these strategies, discusses their benefits and limitations and presents energy modeling results for the strategies for a large office project.

Automated tools facilitate an ongoing commissioning process to improve occupant comfort, ensure the persistence of correct system operation and reduce energy consumption. These tools decrease the time and the skill level required to carry out necessary quality assurance measures, and as a result they enable more thorough testing of building heating, ventilating and air-conditioning (HVAC) systems. This paper describes the algorithm developed by the U.S. National Institute of Standards and Technology (NIST) to analyze chiller loops and presents the results of a passive monitoring investigation using field data obtained from BACnet controllers and field validation of the findings. The tool was successful in detecting faults in system operation in its first field implementation for performance monitoring.

Design of chilled water plants has a very large impact on building energy uses and energy operating costs. This paper proposes a design tool for optimal design of chilled water plants. The tool that integrates system models with a genetic algorithm optimization solver minimizes the life cycle cost by finding the design variables such as chilled water and condenser piping diameters, chilled and condenser water temperature differences and chilled water supply temperature. The proposed modeling methods depend on detailed cooling load analysis and head and energy calculations. The pump head calculations including piping, all fittings, valves, and devices are achieved by using the Darcy-Weisbach equation with given flow parameters. The energy calculations are done by using generic chiller, fan, and pump models. The hourly cooling loads need to be obtained from any energy simulation software. The method is tested on an existing three-story, eighty-eight thousand square foot building.

A preliminary evaluation of the performance of a consumer-based control system was conducted by the Oak Ridge National Laboratory (ORNL) and Southwest Gas as part of a cooperative research and development agreement (CRADA) authorized by the Department of Energy (DOE) (Mahderekal et al. (2013). The goal of the research was to evaluate the low-cost approach as a solution for implementing a supervisory control system for a residential gas-operated heat pump. This technical paper explains the research process. A robust data set was produced that allowed detailed assessment of the reliability and the operational performance of the newly developed control system. Experiences gained from the test provided important points of improvement for subsequent evolution of the heat pump technology.

While the design and installation of Variable Refrigerant Flow systems is not inherently difficult, there are nuances and details specific to these systems that if overlooked can lead to costly repairs, poor comfort control and improper system operation. This seminar discusses methods of mitigating potential issues before they occur and reviews best practices and considerations for equipment design and selection, contract documents, functional testing and installation quality control.

This seminar reviews lessons learned from projects utilizing VRF systems from the perspective of the commissioning agent. The importance of properly commissioning these sophisticated systems, means of identifying and addressing common oversights found in various project stages and developing realistic plans for incorporating commissioning into a projects scope are discussed. Additionally, examples and lessons learned from projects the speaker has personally been involved with are reviewed to further improve the confidence among industry professionals responsible with commissioning these systems.

Thermodynamically, the application of heat recovery to kitchen exhaust air is very attractive to design engineers and foodservice facility managers. Exhaust air temperatures are significantly higher than space conditions (due to heat load from the cooking equipment) and the makeup air heating loads are recognized as a major energy end use within foodservice facilities. Because of the recent advances in commercial kitchen ventilation, the potential for heat recovery is more viable than ever before. This seminar presents the potential for energy recovery and the technologies that have recently taken advantage of the opportunities for heat recovery in commercial kitchens.

This seminar discusses the results of the application of commercial kitchen hood grease filters with integral air to water heat exchangers. Topics in this seminar include a system overview, recommended applications, energy advantages and grease extraction and hood system cleaning advantages.

Utilizing various technologies, today’s Clean In Place hoods reduce water consumption while providing labor savings and increased employee safety but at what cost? With rising minimum wages, increasing labor and utility costs, does a compelling business model exist to offset the initial capital and long term investment? This presentation focuses on validating the variable costs.

DCKV systems are becoming more popular as food service designers strive to achieve higher energy savings. However, DCKV systems can be a challenge for energy modelers due to unknowns with expected system operation and lack of features in modeling software. For example, varying the rate of exhaust and makeup air in relation to cooking process heat, smoke, or vapor load is not explicitly modeled in available software. This presentation highlights modeling methodology for three popular energy modeling software packages and provide tips for work-arounds.

Thermal response tests (TRTs) are often conducted to inversely estimate the design parameters of borehole heat exchangers (BHEs); those are the effective thermal conductivity of ground and borehole thermal resistance. TRT can only provide the design parameters of a borehole heat exchanger, but it cannot provide the transient heat exchange rate of installed BHE which represents the actual performance of installed BHE. This paper proposes an estimation method of TPT that can provide both the thermal performance of BHEs and design parameters that usually obtained from TRT. Results showed that the performances of BHEs strongly depend on the inlet temperature. Additionally, transient heat exchange rates obtained from TPRTs provide valuable information on BHE performances that can be used for the design of BHEs.

The heat recovery ground source heat pump (HR-GSHP) system that has several types of GSHPs for different uses connected in the ground heat exchangers yields two types of heat recovery effects. The first one is the direct heat recovery effect obtained by operating the several types of GSHPs. The second one is the indirect heat recovery effect that utilizes the underground thermal storage effects and is brought by alternately operating the several types of GSHPs in the short term. By utilizing these two effects, the HR-GSHP can yield both energy saving effect and drastic reduction of the ground heat exchanger’s total length. This paper investigates the design and operation method of the HR-GSHP system.

In office buildings, the use of a Gas Heat Pump air-conditioning systems may be able to meet thermal demands with the same efficacy as a conventional electrical system while reducing energy demand of the whole building. This paper investigates technically, ambient and economically the substitution of a conventional air-conditioning system of an existing office building by a Gas Heat Pump air-conditioning system. The analysis was conducted through a data assembling of the potential of retrofit of operating office buildings in the city of Sao Paulo; through interviews with mechanical engineers and consultants; and through a case study developed in an existent office building, using computer simulation to evaluate energy performance of different air-conditioning scenarios.

Pollution Control Units have been used in the marketplace for several years. However, with increasing pollution control regulation, and the boom of mixed-use (residential / commercial) complexes, there has been a significant increase in the use of these products. This led to a stronger demand for standardized safety requirements. This session focuses on the timely development and publication of UL8782, Outline of Investigation for Pollution Control Units for Commercial Cooking Operations released January 30, 2017. This session also reveals plans for inclusion of these requirements into the appropriate ASHRAE Standards and installation Codes.

Pollution control units (PCUs) utilized for commercial kitchen exhaust is increasingly more common due to tighter environmental regulation, as well as a greater propensity to install foodservice establishments in population-dense and mixed-use areas. This presentation explains the process of selecting and applying the scrubbing device for commercial kitchen exhaust air.

Balancing performance, capital costs and cost of operations; Electrostatic Precipitator based pollution control units have been providing reliable cost effective smoke and odor abatement for nearly four decades. This presentation focuses on the performance deliverables of these units and where the application of this technology makes great sense.

The use of ozone generators in CKV exhaust treatment is a new technology recently introduced to North America, yet one that has been in widespread use throughout Europe for about a decade. Although ozone is already applied in many areas of science and industry, this presentation focuses upon its use in CKV. Topics covered include methods of production, benefits realized, limitations and code-compliance requirements for grease applications.

Thermal load management studies have been carried out at small and large scale, covering all the range from a single building to the country level, although prior research provides valuable information on the possible energy management schemes and gains, the large scale studies typically suffer shortcomings. This paper addresses those shortcomings focusing on the existing building stock. It describes a comprehensive tool to estimate the potential for thermal load management at large scale accounting for the buildings passive storage potential. The paper also describes the application to a 10 buildings case-study in Geneva (Switzerland) and quantifies the associated gains.

Energy efficiency in buildings is one of the key measures to tackle global energy and emission concerns. The large share of air conditioning in commercial buildings makes air conditioning systems as primary targets for retrofitting. This paper studies 50 commercial buildings in Singapore that have undergone chiller plant retrofitting. The energy audit reports from these buildings are studied in detail to gather data related to building energy consumption and chiller plant efficiency (measured in kW/RT). The energy utilization index (EUI) which is measured as the total energy per square meter is analyzed for these buildings before and after retrofitting.

Commercial buildings alone are responsible for 36% of the total United States electricity consumption, and on average 30% of this electricity consumption is wasted. One of the greatest challenges in improving building energy efficiency lies in the ability to do simple and non-intrusive disaggregation. Building energy disaggregation extracts system and equipment level energy signals from a whole building’s energy consumption data. This paper proposes a novel unsupervised non-intrusive building energy disaggregation technique using 15-minute interval whole-building energy consumption and weather data. The proposed disaggregation technique consists of an analysis loop with three steps.

Benchmarking energy use can help building owners and managers to assess building energy performance and to identify energy efficiency opportunities. Energy consumption data makes it easy to understand the energy use characteristics of each building, and can promote occupants’ awareness of building energy efficiency when providing an energy performance index developed from this data. As a way of improving energy efficiency in the building sector, the Korean government has developed a nation-wide integrated energy consumption database with more than six million building records. This paper introduces the framework of the national building energy consumption database and to analyze energy use characteristics of office buildings across the country.

Knowledge of occupants' interactions with building components and systems and how indoor environments are influenced in response to occupant behaviors is highly beneficial to operate and maintain existing building more efficiently and to design new buildings to be more comfortable and energy-conscious. This paper provides insight in this regard. To this end, occupant behaviors and energy flows are being monitored in an academic building in Ottawa, Canada. The paper presents results of this monitoring campaign on occupants' presence and behaviors, indoor environmental conditions, and energy demands in various offices.

The experimental performances of a dual-mode CO₂ heat pump system coupled with hot and cold thermal storage is investigated in this paper. This combined system was tested by controlling compressor frequency, expansion valve opening and hot and cold circulation water flow rates. Experimental results show that high compressor frequency benefits the combined system performances. Expansion valve opening affects the thermal stratification of thermal storage tanks very slightly. Low hot and cold water flow rates are good for the thermal stratification of thermal storage tanks although high water flow rates can enhance the COP of heat pump system; and thermal stratification in thermal storage tanks is one of the most important impact factors on the COP of heat pump.

Growing concerns about climate change, new decarbonization agenda, research for energy independence and geopolitical evolutions have led countries and industries to rethink their energy consumption. In this research for sustainability, major stakeholders in the UK food retail market are investigating pathways to reduce their carbon footprint. Low-carbon energy production technologies such as photovoltaic systems coupled with battery storage constitute potential solutions, also driven by rising electricity bills. The purpose of this paper is to develop an end-user optimization model assessing potential benefits of photovoltaic systems associated with battery storage for commercial buildings integration.

This paper discusses new methods for the operation of interacting simulating models. These methods provide tools to step into optimization of combinations of integrated energy systems. The main design issues that are addressed are hydronic flow system and the sizing of storage systems. The hydronic layout is important with respect to utilization of exergy i.e. water temperature, but the research also shows the importance of control strategies on energy savings. A proposed new hydronic layout and control design are described in this paper, as applied to heating, cooling and storage systems.

When modeling an HVAC system using fan powered terminal units with EnergyPlus, the user must enter values for fan total pressure rise and fan/motor efficiency. A recent study found that for an 8 inch inlet (203 mm) series fan powered terminal unit, the fan total pressure was considerably lower than values commonly recommended in online training sources. Values in that study were on the order of 0.25 in. w.g. (63 Pa) and not 1.5 or even as much as 3 in. w.g. (374 – 747 Pa). Manufacturer’s performance data were used to verify and extend VAV fan powered terminal unit total pressure rise measurements as determined in a previous study.

The current version of ASHRAE Standard 170 procludes natural ventilation in all spaces in healthcare facilities. This work-group suggests it should be allowed in most healthcare spaces, except for Operating Rooms, Procedure Suites, Sterile Core areas, Interventional Radiology or Cardiology Spaces, Airborne Isolation Areas, and Protective Environments. Natural or mixed-mode ventilation designs may offer some benefits. Among the most likely are energy reduction and enhanced occupant satisfaction. Less likely benefits may include enhanced indoor air quality and a more beneficial microbiome. When considering natural ventilation in health care, designers must fully address the fundamental challenges of space appropriateness, climate appropriateness, acoustics, security, and outdoor air quality. Projects implementing natural ventilation should anticipate commissioning challenges.

The energy consumption of the heating and cooling coils of the air handling units of an educational building with multiple laboratories has been evaluated and suitable energy recovery methods were assessed in an attempt to reuse the energy lost in the exhaust air stream and promote energy conservation while complying with the current building codes. The HVAC system of Life Sciences II (LS II) building of Southern Illinois University Carbondale, is a constant air volume (CAV), 100% outside air (OA) system due to the many laboratories in the building. It is one of the most energy intensive buildings on campus.

The adoption of energy efficient standards significantly cut the energy consumption in buildings by reducing envelope heat transfer and internal heat gain. These energy efficiency measures reduce not only the electrical load but also the cooling load as well as the supply airflow rate. As a result, additional reheat is typically required to maintain the minimum airflow setpoint under partial space cooling loads for conventional air handling units (AHUs) and may degrade the effectiveness of energy efficient measures. The AHUs with return air bypass (RAB) provides an alternative to reduce additional reheating and overcooling at the minimum airflow rate with good space humidity control. The purpose of this paper is to investigate the energy and control performance of the AHUs with RAB under different operating conditions through simulations.

In most HVAC systems, water is usually delivered by several centralized pumps, which may reduce the pumping system’s energy efficiency because of unnecessary pressure loss. A decentralized pumping system is an alternative system that only circulates the minimum water required by the respective terminal unit and can reduce the excess pressure loss. This paper verifies the performance of the decentralized pumping system by conducting an experiment comparing centralized and decentralized pump systems under various water flow conditions in terms of their energy consumption in water delivery and their energy saving potential.

District cooling means producing cooled water in a centralized plant and distributing it in pipelines to a number of buildings to cool the air in each building’s air conditioning system. This paper investigates the effect of the wind speed and direction on cooling towers' thermal performance. Moreover, the distance between stacks, cooling tower fan speed, and effect of wind barriers were also simulated. A three-dimensional Computational Fluid Dynamics (CFD) model of a power plant cooling towers is utilized to assess the effect of flow circulation air on entering air wet bulb temperature under different ambient conditions and orientations.

Texas A&M University’s Main campus has its heating and cooling district to provide needs of both heating hot water (HHW) and chilled water (CHW) to over 230 buildings. Commonly, buildings exceeding the plant static pressure level experience negative pressure in their tallest parts, allowing air into the system that reduces heat transfer efficiency, causes noise, and increases corrosion. The negative pressure also results in consuming much more pumping power due to the requirement of lifting water above plant static pressure to above top building coil. This paper identifies the reason for the negative pressure, and a pressure distribution analysis was performed on the campus thermal loop.

Chiller plants are commonly used to provide cooling water to data centers. While chiller plants are designed for the maximum projected heat load, majority of data centers produce a fraction of the design load. Chiller plants that operate at partial load may not perform efficiently. Evaluating the performance of a working chiller plant is challenging because of the limited data available at the site. Moreover, it is not possible to know how the system will perform after making an adjustment to improve the efficiency. This paper illustrates the use of a scientific approach based on the Flow Network Modeling (FNM) technique for improving the operating efficiency of a real-life data center in Rochester, NY.

This presentation provides an owner’s perspective on operating a net positive energy and water building. This includes an overview of the project, including goals, design, completion and operation of the building; the cultural shifts of staff who came from a traditional closed office environment and moved to a net zero open office environment; findings from formal polling about staff satisfaction that uncovered both the challenges and tangible benefits that have emerged since opening; and how building green has enhanced the organization’s mission.

This presentation provides the challenges and lessons from designing and operating a net zero energy building from an engineer’s perspective. This includes how daily energy reports and dashboards were used to diagnose problems; defining the energy implications of rainwater harvesting and how to further reduce that energy use; how operational data can inform assumptions for future designs; how to balance staff comfort with energy conservation; and the effectiveness of natural ventilation in mixed-humid climates.

This presentation highlights the results of an effort to evaluate energy and Indoor Environmental Quality (IEQ) performance of a net zero energy building from occupants’ perspectives during its first year of operation. The assessment was performed based on the ASHRAE Performance Measurement Protocols (PMP) for Commercial Buildings. This includes an occupant IEQ satisfaction survey along with continuous measurements of selected energy and IEQ variables with occupancy. Lessons learned from the assessment are presented, including evidence that a net zero energy building can deliver high standards of comfort to their occupants.

As the demand for solar electric systems grows, design professionals are looking to add solar PV as an option for their customers. This session covers grid-tied PV systems and provides attendees a solid understanding of the various solar PV components such as PV modules & inverters, system sizing, array configuration, shading analysis and estimation of energy production of a solar system based on site specifics including orientation and tilt angle. Also, different mounting and tracking systems is covered.

Larger buildings electrical rates typically allocate the cost of electricity towards demand. The cost for demand can be similar or even exceed the cost of energy. Because of this, the economics for large buildings PV systems are less favorable when only the energy cost savings are considered. The rational to not attribute demand savings to the PV system have been that a cloud can reduce the output for 15 minutes and the peak for the month or year will be set. This presentation demonstrates that demand savings should be included in the economic analysis of PV systems.

The installed cost of solar photovoltaic installations has decreased significantly in the past decade. In some areas of the U.S.A. and many parts of the world, the long term 20 year cost of solar PV electricity is equal to or cheaper than the grid. However, the first cost hurdle must still be overcome by commercial projects. Tax credits, third party financing, third party ownership and other methods are discussed to give project design professionals a full understanding of the options available to move toward your Zero Net Energy Buildings.

Sustainability begins with preservation - maximizing the use of existing materials and infrastructure, reducing waste and preserving the historic character of older towns and cities. Land availability surrounding the locations/sites of most of historic and heritage buildings, original bioclimatic adaptability and currently available environmental technologies, including HVAC and mature technologies of renewable energies supply systems, can supplement inherent sustainable NZEB’s features without compromising the unique historic character. Presenting studies (Aviation Museum and Institute for Conservation) addresses methodologies, current knowledge and technologies use in refurbishment design process, as well as importance of relevant benchmarking, rating system and financing scheme development.

The Walgreens Net Zero Energy store in Evanston, Illinois opened in November of 2013 and now has over three years of operating data. The project incorporated an innovative heat pump technology with a vertical well geo-exchange system and a central heat pump system that provides chilled water, heating hot water and services the refrigeration cabinets. Detailed performance data has been collected on the building and the geo-exchange field. This study explores the benefit of the geo-exchange system and the lessons learned from operating a net zero energy building. The project won a 2016 ASHRAE Technology Award.

The first documented net zero energy school in the United States was Richardsville Elementary in Warren County, Kentucky. One of the latest net zero energy schools is Discovery Elementary in Arlington, Virginia. This presentation addresses how geothermal heating and cooling was used to reduce the building energy requirements in these two schools and how net zero energy designs have evolved in this short period of time.

The Olver Transit Center in Greenfield, Massachusetts is the first net zero public transportation center, using geothermal heat pumps, a 7300 sq ft ground mounted PV system and an on-site wood pellet boiler. The geothermal and pellet boiler are supplemented by air preheating with a solar wall and energy heat recovery. It includes office space on the second floor and is designed to also serve future rail service.

The new Cincinnati, OH police station completed in late 2015 was intended to be a design-build LEED silver, but the winning bid showed that a net zero building could be built within the available budget. Forty geothermal bores with decentralized low-head pumps and 2-speed heat pump units greatly reduced the HVAC energy usage. Water-to-water heat pumps are used for domestic hot water and garage underslab heating to balance annual heat rejection and extraction. The building is always open for business and includes fitness/locker facilities, public spaces, offices and classrooms and a garage for police cruisers, each with unique IAQ requirements.

This seminar discusses lessons learned at Fort Huachuca over the past 35 years with various renewable systems, including indoor pool solar water heating; solar domestic hot water; grid connected PV; transpired air solar collectors; daylighting; PV outdoor lighting; a dish/Sterling solar thermal electric generation; building integrated PV; utility owned 13.6 MW (AC) PV; and organic Rankine cycle electrical generation.

The US Army requires that projects install solar thermal arrays to provide 30% of domestic hot water load when there is an economic payback. There are challenges, however, improperly sizing a system to meet these design loads and verifying that the system meets the requirements is not required. This presentation looks at an Army barracks that specified an array that would meet 70% of the domestic load but encountered many problems during commissioning and the first 6 months of operation. Lessons learned and recommendations for future projects are presented.

Passive house standard are among the highest in relationship with building envelope. Since building envelope is a key component in net zero buildings, many of the design procedure can also be applied to net zero buildings. This presentation covers the fundamentals and climate considerations with designing passive construction.

Pennsylvania State University’s GridSTAR Experience Center, located at the Philadelphia Navy Yard, features a near net zero energy building. A unique combination of building materials, construction methods, energy management strategies and renewable energy sources were employed to approach net zero. Research was conducted to evaluate building energy and envelope performance. The results of the measured building energy performance were compared to whole-building energy simulations and one-dimensional hygrothermal modeling. This presentation covers important envelope considerations and lessons learned to achieve near net zero energy residential buildings.

Net zero and passive buildings are intrinsically air tight. This can present challenges if the envelope and HVAC systems are not correctly designed. This presentation covers hygrothermal fundamentals as well as design and modeling considerations for building envelopes in passive and high efficiency buildings.

This presentation highlights the overall goals of Standard 90.1, specific goals set for 90.1-2016 edition. This presentation also covers the major changes of format, new climate zones, major changes in the envelope requirements and their applications in building design and construction.

This presentation covers the major changes in lighting and power requirements of 90.1-2016. The presentation also provides insights into appropriate application of the major new requirements so engineers and designers will receive a better understanding of the design changes needed to meet the new requirements.

This presentation covers the major changes in mechanical requirements of 90.1-2016, including equipment efficiency updates and system requirement changes.

Standard 90.1 has traditionally included two paths for compliance: the prescriptive path and performance path (also known as the Energy Cost Budget Method). The 2016 standard establishes a third path: a stable whole building performance method. This presentation provides an overview of this new fixed-baseline compliance path and explains its appropriate application and how this new path could encourage the innovative designs to eventually achieve net zero energy buildings. This presentation also summarizes the energy savings from Standard 90.1-2016. 

Design for affordability incorporates thoughtful floor plans, thermal envelope, water distribution systems and HVAC systems to minimize costs and maximize benefit to cost ratio. This presentation provides detailed information on key design elements of affordable high performance homes. Case studies of successful application of these principles in affordable ZNE homes are summarized, along with insights on creative approaches and challenges when trying to apply cost-effective solutions to real-world affordable new construction.