ASHRAE members are often confronted with ethical issues (whether they realize it or not). This session is part of a continuing program under which ASHRAE members engage in an interactive session where participants are presented with two NPSE ethics cases, discuss the cases in small groups and then reveal their decisions. The actual NSPE decisions are then provided. Test your "Ethics IQ" against real cases and receive CE credit in the process.

ASHRAE members are often confronted with ethical issues (whether they realize it or not). This session is part of a continuing program under which ASHRAE members engage in an interactive session where participants are presented with two NPSE ethics cases, discuss the cases in small groups and then reveal their decisions. The actual NSPE decisions are then provided. Test your "Ethics IQ" against real cases and receive CE credit in the process.

ASHRAE members are often confronted with ethical issues (whether they realize it or not). This session is part of a continuing program under which ASHRAE members engage in an interactive session where participants are presented with two NPSE ethics cases, discuss the cases in small groups and then reveal their decisions. The actual NSPE decisions are then provided. Test your "Ethics IQ" against real cases and receive CE credit in the process.

Demand controlled ventilation (DCV) systems use sensors—generally either CO₂ or occupancy sensors—to estimate the actual number of people in an area and supply only as much ventilation air as is needed at that time. This can save substantial energy over the traditional method of ventilation which assumes that all spaces in a building are at peak occupancy at all times. But while DCV has been in use for over 20 years and its theoretical impacts have been well demonstrated, little is known about the actual operation and energy performance of these systems in real buildings. And even less is known about the performance of DCV for complex multizone systems. This paper helps fill this information gap by covering a field study of DCV systems that we recently conducted in multizone HVAC systems in the upper Midwest. After gathering information on a broad number of actual DCV systems installed in this region, the authors have measured, analyzed and demonstrated the impact of DCV in a subset of six such systems.

The biowall is a plant-assisted air-filter that is integrated with the central HVAC system on a home to improve indoor air quality and has the potential to reduce energy consumption. The biowall concept has been evaluated in a laboratory setting and a pre-commercialization prototype has also been installed in a model home for further evaluation. This paper summarizes the laboratory and field demonstration work that has been accomplished since 2014. It is expected that a biowall can reduce the outside air requirements for IAQ by up to 50% which could subsequently reduce HVAC energy consumption by 30%.

Displacement ventilation systems have found increased usage in recent years and have been shown to reduce energy consumption while satisfying the required indoor air quality (IAQ) standard. The system takes advantage of thermal buoyancy effect to displace warm air and light containments above the occupant breathing zone. This makes the displacement ventilation system a good candidate for cooling spaces with high ceilings. Despite the advantages of this system there are still questions on the system ability in removing CO2, which has a higher molecular weight than air. The current paper investigates the CO2 concentration from occupants in an interior office with a displacement ventilation system.

Details of a three year submetering project to install web based meters for all campus buildings is presented.  The use of this data to target under-performing buildings for energy projects will be presented.  Details of how the metering data for multiple uses such as energy dashboards, energy benchmarking, energy project baselining, and monitoring based commissioning will be presented.

This presentation describes the various ways USD utilizes advanced submetering in their building automation system.  Initially installed to assist in measurement and verification of energy performance contracts, USD’s building meters are used to track energy project savings in an ongoing retrocommissioning effort.  The role that energy tracking has played in USD’s successful and repeated commitment to fund energy efficiency projects will be presented.

Many buildings with large, high-bay areas suffer from high energy cost in the winter months due to inefficient equipment, poor system layout and thermal stratification. While various strategies are available to heat and ventilate the building, some technologies can meet these heating loads with greater energy efficiency, improved temperature control and other operational benefits. This presentation provides an overview of 100% outside air, HTHV (High Temperature Heating and Ventilation) direct-fired heating technology for high-bay commercial buildings and discusses the findings of a recent field study outside St. Louis, MO.

This paper describes the study of an IT office building where radiant cooling system and conventional VAV has been installed for the performance assessment. The paper details the calibration of whole building energy model to component level; lighting, equipment and HVAC components like chiller, pumps, cooling towers, fan etc. Also, a new methodology for the systematic selection of influence parameter has been developed for the calibration of a simulated model which requires the large time for the execution.

The design-build construction method presents opportunities and challenges to all the groups involved in a construction project.  This paper will explore how the mechanical and electrical designers and contractors addressed these opportunities and challenges for the recent Byron G. Rogers Federal Office Building modernization project in downtown Denver, Colorado.  The project involved approximately 500,000 square feet of renovation and deep energy retrofit in an existing high-rise building  which is anticipated to to be added to the National Register of Historic Places in the future. 

The heating, ventilation, air conditioning and refrigeration industry shows a trend toward increased adoption of condensing boilers in heating systems, but the full impact on design and construction is complex. The maximum efficiency of condensing boilers can significantly exceed that of non-condensing boilers at lower return water temperatures. However, in order to reach lower return water temperatures, coils must be properly selected. A standard coil selection exhibits a tendency to produce a smaller change in temperature with lower water temperatures. As a result, pumping energy increases due to the increased flow required to supply the same heat energy. This paper investigates the effect on overall system performance and construction cost of various heating system metrics with regards to condensing and non-condensing boilers.

While BIM represents the future of project delivery, the present, especially for MEP trades, requires creativity and imagination to compensate for BIM tools that are currently immature and incomplete.  This is compounded by an industry still finding its swim lanes as the BIM centric integrated project delivery system forces all parties to blur their scope lines.  This presentation discusses the disconnect between the process and product, the tools and deliverables, the expectations and outcomes.  The presentation will also provide guidance on dealing with the uncertainty and fill in the missing pieces to bring the project team together.

Project teams are having to use multiple software platforms for various reasons (BIM, energy, daylight, etc…) so one software package may never do it all.  But there are commonalities that can be leveraged on each project to ensure successful delivery. Hence, it can be argued that seamless interoperability is unlikely to be universally successful or widely adopted, and may actually stifle creative workflows.  Rather, the success of BIM to BEM will need to focus on collaboration that results in a project-specific BIM to BEM workflow between relevant team members.  This session will outline a framework for this successful collaboration.

BIM technology currently has been used not only during construction document stage, but also during initial stage. The good implementation of the BIM to BEM will enhance collaboration process among architect, engineer and energy modeler. However, the application in projects is still limited. The presentation will explore interoperability between BIM and BEM and collaboration among disciplines in early stage. Additionally, how the simulation results can drive better performance building and provide faster opportunities to identify different energy efficiency measures will be highlighted using case studies to show the implementation and lesson learned from the process.

Many of you may be familiar with ASHRAE at the Chapter level. This seminar covers the structure of the Society from committees to councils and everything in between. We love our acronyms and when we’re done, you’ll finally know what they all mean and how you can get involved.

Now that you’ve got your bearings and know the difference between a TC and a TG, this seminar tells you about the softer side of ASHRAE. You’ll find out what social events you shouldn’t miss and how to make the most of your conference experience.

Lubricants optimized for R-404A refrigerant may not be the best choice for the new low GWP alternatives. In this study, selected low GWP alternative refrigerants to R-404A are evaluated with several synthetic POE lubricants of systematically varied chemical structure and correspondingly varied compatibility with these refrigerants. The results of laboratory and full system tests are correlated to the measured thermo-physical properties and miscibility of the refrigerant/POE mixtures. Combining the property information with full system test data allow for analysis of the impact of refrigerant-lubricant mixture properties on system performance.

The commercial transition to low global warming potential (GWP) refrigerants that can benefit environmental impact does not preclude the need to consider the interactions/stability  between the lubricant and refrigerant.  Dealing with some low GWP refrigerants, it becomes even more essential to investigate and understand these interactions due to potential property differences these refrigerants have over refrigerants used today.  This presentation will outline key interactions that need to be studied along with examples of lubricant options for some low GWP refrigerant candidates.  Low GWP refrigerants based on various natural and synthetic chemistries will be assessed.

Low global warming potential (GWP) refrigerants have been studied by the HVAC&R industry extensively with limited success in finding optimal design compatible replacements for all product segments. New ultra low GWP olefin refrigerants such as HFOs are being considered by themselves or blended with traditional refrigerants to optimize design attributes for equipment manufacturers, but there can be compromises that develop in other design attributes.  This presentation will provide a summary of the design trade-offs when considering new refrigerants and the product differences associated with new lower GWP refrigerant products that are being introduced by the HVAC&R industry.

The ASHRAE Load Calculations Application Manual has been updated to include results from more than
four years of ASHRAE research. This presentation will give an overview of the state-of-the-art with an
emphasis on the new methods and data in the 2nd Edition of the Load Calculations Application Manual.

Air conditioning system sizing is an important aspect of the early building design process.  Calculating cooling and heating loads can be challenging when all of the details regarding building construction and function are not well-defined.  Making reasonable decisions and assumptions in the schematic design phase of a project is critical to selecting and applying proper HVAC solutions.  This presentation will provide some guidance on these decisions and how they impact the building design process.

Load calculations require application of engineering judgment gained by experience, hard knocks and bullets dodged.   Understanding the impact of each assumption is key to reaching a reasonable result within time constraints of modern fast-track design processes.   Young engineers need to be able to recognize results that look unusual - and be able to backtrack and find their mistakes, not blindly use results because the computer says so.

The cooling performance of a raised-floor data center is dominated by its ability to deliver adequate cooling airflow to IT equipment through perforated tiles. Although many studies have focused on the design of plenum systems and the use of Computational Fluid Dynamics to predict tile airflow rates, very little has been published regarding accurately measuring airflows in existing facilities. We investigate the ability of a commercially-available passive flow hood to accurately measure data center tile airflow.

Energy efficiency has become increasing important in the data center industry, driven by rising energy prices, environmental legislation, corporate social responsibility pressures and competition. Energy efficiency is part of sustainability, however consideration of other aspects such as the embodied environmental impact of materials, components and systems are needed for a holistic view of sustainability. Life cycle assessment areas of protection may be defined as climate change, ecosystem quality, human health and resource depletion. The industry is starting to become more aware of these issues and developing metrics to quantify performance. This paper describes key data center sustainability issues and proposes how the industry should approach its environmental responsibilities in order to capitalize on the business opportunity as well as demonstrating sustainable leadership.

A number of studies reported associations between ground-level ozone and various adverse health effects, including respiratory and cardiovascular diseases. Indoor ozone is also a significant initiator of indoor chemistry by driving various oxidative processes which produce many harmful oxidation products. Hence ozone is the required challenge gas with respect to oxidizing gases to be tested in AHSRAE Standard 145.2-2011. In practical application, how often the filters should be changed on specific operation condition is a key question. Wheeler-Jonas equation is widely used for describing breakthrough curves of VOCs removal by granular activated carbon (GAC).  This paper will investigate the applicability of W-J equation to the oxidizing gas - ozone. The experiments will be conducted on a state-of-the-art full-scale filter test rig. The air tightness, uniform distribution of challenge gases and stable temperature and humidity control of the test rig have already been validated. Commercially available AC filters with different pore sizes, specific areas and bulk densities will be tested.

Institutional campuses often times encompass both centralized and decentralized heating and cooling systems. Each configuration inherently has advantages and challenges when trying to maintain occupant comfort while minimizing energy consumption.  Recent technological advancements in computing power allows building energy modelers to quickly and efficiently develop models which can be evaluated as part of a centralized plant or as a stand alone system.

ASHRAE is aiming for buildings to achieve net-zero energy use, including energy-intensive mission critical facilities, by the year 2030.  The design methods to achieve this goal are aiming to be in place in less than 5 years, by 2020. There is a need to ensure designers can choose the most beneficial options available.  Often data center heat is considered a bane, and water source energy recovery is not an option because the heat rejection and distribution is limited by physical, monetary and temperature aspects.  However, opportunities are becoming more available for new and existing facilities as data center densities and water cooling temperatures move steadily higher. This paper reviews the potential benefits of operating with higher water temperatures and finding means to couple alternative systems as heat sinks for modern data centers.

Data centers have an extensive range of complicated system design choices, which can often times seem overwhelming when deciding the best way to maximize the system design for reliability and energy efficiency. Is an air-side or water-side economizer system better, or should an indirect system be used over a wet-bulb economizer design? Is the industry moving away from raised floor designs to installing server cabinets directly on slab? High-level decisions can be complicated, but diving further into the details reveals even further trade-offs and directions in designs. Should containment be done on the cold-aisle or hot-aisle? Is it better to select units with EC fans or VFD equipped motors? The authors present a range of topics for debate in data center design and discuss the strengths and weaknesses of each, applicability and limiting factors as well as encourage participation in discussions about highly contested topics in the data center industry. These debates are happening right now across designers and operators, end users and owners and produces a variety of viewpoints and engaging discussions on complex systems design.

This session illustrates doing a better job serving the needs of most commercial buildings by utilizing “Low Flow/High Delta” water based systems.  Water has a high affinity for energy and we should be using it in a much wiser fashion. This presentation will illustrate how to use water based systems to transfer energy more efficiently, save operational expense, help control systems operate with greater ease, and open other benefits to the overall building design and operation.  Lessons learned will be illustrated on the application of “Low Flow – High Delta” water based systmes.

This session illustrates doing a better job serving the needs of most commercial buildings by utilizing “Low Flow/High Delta” water based systems.  Water has a high affinity for energy and we should be using it in a much wiser fashion.  This presentation will illustrate how to use water based systems to transfer energy more efficiently, save operational expense, help control systems operate with greater ease, and open other benefits to the overall building design and operation.  Lessons learned will be illustrated on the application of “Low Flow – High Delta” water based systems.

Ground source heat pump (GSHP) systems are commonly used in Sweden for both residential and commercial buildings.  However, there are several key differences with GSHP systems utilized in the USA. Scandinavian systems are often heating-only, and instead of using grouted boreholes, groundwater-filled boreholes are often used.  These boreholes are cased from the ground surface to the usually-shallow bedrock.  A single or double U-tube is commonly suspended in the borehole.  These boreholes are often deeper than those commonly used in the USA.  This paper reviews current Scandinavian practice for borehole design and discusses several installations with boreholes 250 – 300 m (820-984 ft) deep or deeper.

The purpose of this paper is to explore the performance of shallow depth helical heat exchangers coupled with ground source heat pumps (GSHP) for residential HVAC applications.  This shallow depth system serves as an alternative to traditional vertical bore fields, which carry high installation costs.  These helical heat exchangers occupy considerably less land when compared to horizontal configurations, but are still influenced by changing ground temperatures driven by seasonal weather conditions.  Performance data and design information is limited for helical heat exchangers, which has limited their adoption amongst GSHP system designers and installers.  In Situ testing was performed for a GSHP system to provide designers with performance information and insight towards appropriate applications of this technology.

Heat pumps use less energy when the difference between the source and load temperatures is small. For a ground-source heat pump (GSHP), the source temperature is prescribed by the local ground temperature. As for the load temperature, it depends on the type of heating system. In this paper, the performance of a water-to-water heat pump coupled to two different heating systems is examined. The first one is a radiant type floor heating system operating at a relative low temperature (≈30 °C). The second system uses a fan-coil unit operating at higher temperature (≈45 °C) to supply space heat. The objective of the paper is to quantify the energy savings from running a GSHP at a low load temperatures.

Photovoltaic panels that provide electricity and thermal energy are now commercially available. These PV/T collectors use either the air or a liquid as the heat transfer fluid to collect thermal energy. This paper examines the overall system performance of PV/T collectors linked to a ground-source heat pump equipped with a four-pipe borehole. The system selected for this study consists of two independent fluid circuits. In the first circuit, the outlet fluid from a liquid-cooled PV/T collector is first pumped through a heat exchanger then to the ground heat exchanger. In the second circuit, fluid is pumped from the ground heat exchanger to the heat pump via the heat exchanger which provides a thermal link between the PV/T and GSHP circuits.

Studies have shown that neglecting borehole thermal capacity in annual simulations of ground-source heat pump systems can lead to an overestimation of the energy consumption by 3-4% when the heat pump is operating intermittently. There are various approaches to account for thermal capacity when simulating geothermal boreholes. The objective of this paper is to validate the TRCM procedure. Experimental data from two tests performed at the Canadian Centre for Housing Technology (Ottawa, Canada) are used for this validation.

This paper provides an overview of recent refinements to the Radiant Time Series Method (RTSM) as part of 1616-RP. These refinements include replacing the ASHRAE three-parameter (A,B,C) clear sky model with a new globally-applicable model, introducing new design day temperature profiles, updating the weather data, and improving the treatment of interior shading in the fenestration model. In addition, the sensitivity of the calculated cooling loads to the weather-related refinements is investigated with a parametric study.

This paper extends the application of a correlation developed previously by the author for the overall heat transfer coefficients (the U-factors) of single layered fiberglass Metal Building (MB) insulation assemblies to assemblies where insulation is used in a manner designed to fill up the space (the “cavity”) between the two consecutive structural elements (purlins or girts). These assemblies may involve either single or multiple insulation layers and the cavity may be filled to various extents. The paper describes a general technical approach to calculate the thermal resistances of various regions of a MB insulation assembly, namely regions beyond, underneath, and above the structural units.

The occupancy patterns in office buildings have been becoming increasingly diverse. And, even in cases where the occupancy periods are still rigid, the time needed to bring a room from nighttime setback temperatures to the setpoint temperatures not only change in time but also vary between offices. Consequently, operators have been challenged to choose conservatively short temperature setback periods. In recognition of these challenges, a self-adaptive control algorithm that can learn the recurring occupancy patterns and the parameters of a model predicting the indoor temperature response was implemented in a southwest-facing shared office space in Ottawa, Canada.

Stationary gas turbines used in industrial applications can be run using pre-mixed air/fuel systems. Though pre-mixed air/fuel systems are widely established, research continues to further develop the efficiency of such engines. This paper uses computer numerical simulation in analyzing the effects of the pre-mixed air/fuel composition on the performance of a miniature gas turbine. The composition of the fuel-air pre-mixture was varied, results were recorded and compared. Effects on turbulence intensity in the combustion zone for various pre-mixed air/fuel compositions were monitored and compared. The analysis has shown that performance can be optimized with an optimal air/fuel pre-mixture, and that this optimal performance coincides with peak turbulence intensity at the combustion chamber downstream of the pre-mixed air/fuel injectors.

This paper refers to a study on the application of the thermodynamic analysis method proposed by
POPPE to model the thermodynamic behavior of countercurrent water cooling towers, to improve
performance. This method replaces the traditional method used today, more simple and less accurate, proposed by
MERKEL. The objective is to produce a mathematical routine using this method, to be used in supervisory systems in order to optimize the operation of these towers, looking at energy savings.

Early stage design has fundamental impact on building performance as they place significant limits on later design options. The objective of this study was to develop a simplified and scalable approach for optimizing the form, massing and orientation in early design stage. In this approach, a reference building was first defined with pre-selected building materials and assemblies and HVAC system for the intended climate and site conditions. The energy performance of this reference building was estimated by whole building energy simulation such as EnergyPlus at the same time. Heat fluxes and irradiation fluxes received by these interior surfaces of enclosure were also extracted from the reference building simulation.

This paper is about the application of Mixed Methods for design professionals and social science researchers.   The purpose is to describe an intellectual commons which integrates qualitative and quantitative data related to sustainable design and operation of the built environment. Once described, the proposed intellectual commons would include a form of communication based on data described by symbolism and logic to be shared by the broad range of worldviews in our global society. This form of communication models that which is common in the process of problem solving for many academic and professional disciplines.

Designing energy efficient buildings has been traditionally viewed as an optimization problem with a few stipulated constraints which could be tackled by mathematical methods relying on detailed computer simulations. Recently it has been argued that the conceptual building design process should inherently and explicitly contain an interactive process which captures the synergy between automated performance prediction with the human capabilities to perceive, evaluate and ultimately select one (or a few) suitable solution(s). The need to address multi-criteria requirements makes it even more valuable for a designer to know the “latitude” or “degrees of freedom” he/she has in changing certain design variables while achieving preset criteria such as energy performance, life cycle cost, environmental impacts, etc.

Heat losses and gains through opaque building envelopes (such as walls, roofs and floors) significantly affect the overall energy consumption of buildings. To reduce energy consumption of buildings, it is important to ensure that building envelopes exhibit excellent thermal insulation performance. However, the actual insulation performance of building envelopes varies depending on components and construction methods even if the same insulations of equal thickness are used. Therefore, this study aims to evaluate thermal insulation performances of various opaque building envelopes considering thermal bridges and to discuss methods of reducing thermal bridges.

From the late 1940's to the late 1960's, significant efforts were made by ASHVE and ASHRAE to evaluate and quantify the impact of window shading. In the context of the now defunct Shading Coefficient (SC), well known researchers such as Parmelee, Ozisik, Schutrum, Farber, Yellott and Keyes laid the groundwork for much of the work that followed decades later. Of particular interest are the efforts of Keyes, published by ASHRAE in 1967. In that work, he presented measurements of the solar-optical properties of fabrics determined using a custom made apparatus. The main contribution of this work was a method of classifying fabric properties based either on visible inspection, or property measurements. The result was the Keyes Universal Chart, which has been in the Fenestration Chapter of the ASHRAE Handbook of Fundamentals since the 1970's.

Electrocaloric effect (ECE) is the ability of a dielectric to change its temperature and entropy as an electric field is applied and released. It provides an effective means to realize solid-state cooling devices that are environmentally benign and potentially highly energy efficient. Recent breakthroughs are presented in ferroelectric materials exhibiting giant electrocaloric effect, where an adiabatic temperature change DT > 40 ^oC has been obtained in several nano-structured ferroelectrics.  EC cooling devices based on these new materials, as well as challenges and future perspectives are discussed.

ORNL is collaborating with GEA on developing the world's first magnetocaloric refrigerator. The technology could yield energy savings of 25% over baseline vapor compression systems. A drastic upgrade in refrigerator design using magnetocaloric materials (MCM) eliminates the need for refrigerants but creates new challenges ― one is how to transfer heat to or from the solid MCM material using a heat transfer fluid. In this presentation, the basics of magnetocaloric refrigeration and the performance potential will be discussed, followed by describing state of art systems. The technical challenges and potential solutions for this emerging technology will also be reviewed.

Elastocaloric cooling has been recognized as a potential alternative and supplementary technology to the state-of-the-art vapor compression cooling systems. It is based on the elastocaloric effect found in shape memory alloys associated with the solid-solid martensitic phase transformation induced by stress. The fundamental thermodynamics of the martensitic phase change process will be introduced. Elsatocaloric cooling material following the single stage Brayton cycle and the system design will be presented. With the commercially available nickel-titanium tubes, we will demonstrate two compressive elastocaloric cooling prototypes developed in University of Maryland. Experimental test results and potential performance improvement methods will be presented.

While the intent of electronic cigarettes is to promote smoking cessation, studies suggest that the opposite is occurring.  Additionally, the lack of regulations has resulted in an increase in unintentional exposures in young children and nicotine use in adolescents.  This presentation will provide an overview of electronic cigarettes including discussion of the device, its intent, its toxicity and state and federal regulations that may impact its use.

Research indicates that e-cigarette emissions contain much more than nicotine, including aerosolized flavorings, propylene glycol, thermal degradation products and other contaminants that could present health hazards. Because e-cigarettes are a potential source of indoor air pollutants, AIHA recommends that their use in the indoor environment be restricted at this time. The FDA currently regulates only e-cigarettes that are marketed for therapeutic purposes, but has proposed a rule extending its tobacco product authorities to cover additional products such as e-cigarettes. This presentation will summarize the AIHA White Paper, along with research and regulatory and industry recommendations published subsequent to its release.

The rapid growth of e-cigarette use has raised questions about their impact on the indoor air quality of offices and public spaces.  The dearth of available information reveals them to be sources of volatile organic compounds (VOCs) and particulate aerosols that have not been fully characterized.  E-cigarettes primarily emit propylene glycol, glycerin and nicotine in addition to diethylene glycol, nitrosamines, 1,2-propanediol, acetic acid, acetone, isoprene, formaldehyde, acetaldehyde, propaldehyde and various flavoring compounds into the indoor air at varying levels.

ASHRAE publishes many documents which relate to indoor air quality.  Smoking has a significant impact on indoor air quality, so how do these documents deal with smoking?  This presentation will identify the various ASHRAE documents and discuss the different ways they deal with smoking.  Will they all need to be modified for e-cigarettes?

This paper is the first part of two papers that report on the results of the ASHRAE-RP 1468 project. This paper presents an overview of the project and the three volumes of documentation included in the final report. The purpose of the project was to produce reference models and guidelines for developing software to automate thermal model creation from a Building Information Model (BIM) into a Building Energy Simulation (BES) for energy simulations. This paper describes the methods of the research and presents highlights of the guidelines.

This paper presents an experimental and numerical study focusing on the development of control-oriented thermal models of varying resolution for an actively charged/discharged phase change material thermal energy storage (PCM TES) system intended for building integration. This PCM TES system consists of five layers of PCM panels with an air channel between the middle layers. Conditioned air is drawn through the cavity to charge and discharge the PCM. The PCM TES system is tested in an environmental chamber where its dynamic response was carefully monitored. The monitored data is used for model development and validation. Compared to a detailed 30th order RC model, simplified 4th order and 2nd order models are shown to be able to satisfactorily predict the thermal energy storage and release of the PCM TES system. To simplify the PCM characterization input and to reduce the simulation time, a five-parameter equation is developed to model the PCM specific heat and a four-parameter equation for its thermal conductivity. The presented modeling methodology is applicable for similar PCM TES systems with multiple PCM layers and air flow channels.

This paper presents an experimental and theoretical study of the dynamic response of low mass residential buildings and their respective space heating peak demands for different room temperature set point profiles, with a focus on the impact of thermal model resolution on the peak demand calculation. Experiments were conducted at two identically constructed and highly instrumented houses. The wood floor of one of them is covered with carpet. Their dynamic response to different ramping set point profiles is monitored and analyzed. Equivalent and physically meaningful RC network thermal models for the purpose of model based control are developed for a north zone of the houses.

Buildings account for 40% of CO2 emissions in the UK and around 25% in China. In an attempt to mitigate global warming and reduce greenhouse gas emissions, the UK Government is committed to reduce its greenhouse gas emissions by 80% below the 1990’s level by 2050; China pledged a 40–45% decrease in CO2 emissions per GDP by 2020 against 2005 levels. To achieve these targets, building retrofitting is one of the efficient ways to improve building energy efficiency and the associated CO2 emissions. In order to evaluate the potential energy savings that can be achieved through building retrofit plans, this study aims to assess two levels of deep retrofit in a typical office building. These retrofit scenarios are assessed using numerical simulation of a prototypical building in five climate zones in china as well as London and Aberdeen in the UK. Numerical simulations have been conducted using the EnergyPlus software. The outcomes of this study reveal that deep retrofit in office buildings can potentially achieve up to 54% energy saving compared with the energy consumption of buildings designed in 1980(s). However, economic factors should be also considered in the process of decision making to choose the most appropriate building retrofit strategy.

High performance buildings are becoming more prevalent in new Army construction projects. Unfortunately, these new designs often do not take into account preventive procedures to avoid thermal bridging effects which are localized heat flow between the building interior and exterior. These effects become much more significant as buildings are designed to be highly insulated and better sealed against air leakage. Researchers from the U.S. Army Engineer Research and Development Center - Construction Engineering Research Laboratory (ERDC-CERL) visited several Army installations and used infra-red imaging to survey buildings to identify places in the building envelope where thermal bridging commonly occur. Characteristic construction sections were selected for heat transfer modeling to quantify the thermal bridging impact and develop general mitigation solutions. This manuscript presents examples of the developed U.S. Army ERDC-CERL Thermal Bridge Mitigation Catalog, which includes architectural details thermal bridge modeling values (ψ and U-factors), and schematics of good construction practices to improve the building envelope performance of typical Army facilities. In addition, this work includes developed visual step-by-step sequencing examples to be used by the construction practitioner for the assembly of a properly mitigated thermal bridge detail in the building envelope.

The aim of the “School of the Future” project which receives funding within the EU’s 7th Framework Program, is to design, demonstrate, evaluate and communicate shining examples of how to reach the future high performance building level. School buildings, their owners and their primary users, namely pupils (the next generation) are the focus of the project. Both the energy and indoor environment performance of four demonstration buildings in four European countries and climates is being greatly improved due to holistic retrofits to the building envelope, the service systems, the integration of renewables, and building management systems. This paper describes the EU project, including all results, a comparison of the four demonstration buildings, and a detailed description of the German demonstration project.

Many innovative energy-saving strategies have been implemented in energy efficient and sustainable building design to reduce overall energy use and operational cost. However, measurement of the actual energy usage and verification of implemented energy-saving design and strategies are also required to ensure the building performs as expected. This paper presents a comprehensive evaluation of the energy performance at the Iowa Utilities Board and Office of Consumer Advocate (IUB-OCA) building by examining annual detailed sub-metered data.

Many semi-volatile organic compounds (SVOCs) including phthalates and PAHs have been linked to adverse health effects such as endocrine disruption and cancer. Due to widespread use of synthetically produced plasticizers, insecticides, and flame retardant indoors, large amounts of SVOCs persist indoors for relatively long periods (>1 yr). This study investigates inhalation vs. dermal uptake to human surface considering air flow and SVOC transport in the vicinity of a human body.  Using computational fluid dynamics (CFD) simulations of pollutant dynamics around a human body, breathing zone concentrations and SVOC uptake by human surface were estimated for an occupant in ventilated room.

 Siloxanes are common ingredients in consumer products like antiperspirants, skin and hair care products, cosmetics and detergents, and are being promoted as green dry cleaning solvents to replace toxic chlorinated solvents.  The wide applications have caused elevated concentrations of siloxanes in our environments, and the indoor levels are usually much higher than outdoor air. Some siloxanes are regarded as potential endocrine disrupting compounds. The sources, indoor and outdoor air concentrations, and the health and environmental effects of siloxanes will be presented and future research needs will be discussed.

This is the first in a series of technical papers written to describe results of ASHRAE research project 1544. Hot water use in hotels and its associated energy use is significant. However, 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 first paper describes the technique used to locate and solicit participating hotels, details about the hotels tested, and the instrumentation, data collection approach and equipment used in the field test effort.

This is the second in a series of technical papers written to describe results of ASHRAE research project 1544. Hot water use in hotels and its associated energy use is significant. However, 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 second paper describes data collected from a “travel” style hotel having no meeting rooms or commercial food service.

This is the third in a series of technical papers written to describe results of ASHRAE research project 1544. Hot water use in hotels and its associated energy use is significant. However, 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 third paper describes data collected from a “business” style hotel having multiple meeting rooms and several restaurants and thus a commercial kitchen.

The main challenge in understanding cooling performance in a legacy data center is the invisible transport medium (air). This seminar describes a comprehensive experimental characterization of a new data center lab. Airflow and temperature measurements are utilized to understand the facility’s performance at different operational stages. Since the facility houses a wide range of different IT equipment (servers, switches, storages, blades), it is important to understand the airflow demand of each. The IT was tested and flow characterized. The characterization data is integrated via compact models into a full CFD simulation. Measured data from the facility are used for validation.

Localized hybrid air-water cooling in server cabinets remove heat using a self contained system that does not interact with the room level air cooling system is one approach to more effectively control the cooling when there is wide variation in the amount of dissipation in neighboring racks. This seminar describes an experimental test and CFD validation of a commercial hybrid-cooled enclosed cabinet. The model includes fans and channels and the heat exchanger box and uses experimentally measured flow curves for the IT equipment.  A sensitivity study was applied to the validated model to investigate the effect of leakage on cabinets performance.

DCIM provides tools to bridge the gap in terms of process and data communication between facilities and IT, but there is still a gap in terms of the engineering consequences of actions. This presentation will give examples of how common practices, at both the rack and the room scale (including the impact of choosing to co-locate different types of IT), can impact availability, capacity and efficiency in different ways. Metrics will be used to quantify the impact of proposed changes so that the business can make IT deployment and infrastructure decisions in a holistic way to fit its needs.

Automated detection of schedule- and operation-related energy savings opportunities in commercial buildings can help building owners lower operating expenses while also reducing the adverse societal impacts such as global greenhouse gas emissions. We propose automated methods of identifying certain energy efficiency opportunities in commercial buildings using only whole-building electricity consumption and local climate data. Our two-step approach uses piecewise linear regression and density-based clustering to detect both schedule- and operation-related electricity consumption faults. This paper discusses results obtained from applying this approach to two office buildings and two residential buildings meant to demonstrate our model’s effectiveness in identifying such energy efficiency opportunities. Ways by which the analysis results can be conveniently and succinctly presented to building managers and operators are also suggested.

On the establishment of a reliable baselines for energy savings estimation, one or more variables are usually used to determine a model by regression analysis. These regression models generally use one or more independent variables, such as outside air temperature (OAT), degree days, or combination of these with occupancy or humidity. Based in a calibrated multi-use building energy simulation in a hot and humid climates, in this paper the study of the influence of outside air intake fraction on the selection of the best parameter to develop change-point regression modeling for cooling and heating energy use was evaluated. A comparison among regressions based on three variables, two regularly used in measuring and verification (M&V) process – OAT and outside air enthalpy (OAE), plus the addition of an operational enthalpy was carried out. The study included variations of the outside air intake fraction in the range of 10% -100% and the development of the corresponding patterns of regression models for each of the parameters.

Energy modelling and optimization studies can facilitate the design of cost-effective, low-energy buildings. However, this process inevitably involves early assumptions of unknowns such as predicting occupant behavior, future climate and econometric assumptions. As presently practiced, energy modelers typically do not quantify the implications of these unknown into performance outcomes. This paper describes an energy modelling approach to quantify economic risk and better inform decision-makers of the economic feasibility of a project. The proposed methodology suggests how economic uncertainty can be quantified within an optimization framework. This approach improves modelling outcomes by factoring in the effect of variability in assumptions and improves confidence in simulation results. The methodology is demonstrated using a net-zero energy commercial office building case-study located in London, ON.

There is a trend towards high-rise residential buildings with large glazed areas – often floor-to-ceiling. In most climates, these buildings are reliant on mechanical systems to maintain comfort as a result of the poor insulating properties and high solar transmittance of the glazing. In the summer they are prone to overheating from high solar gains; in the winter, they are prone to thermal discomfort due to low surface temperatures and high heat loss through poorly-insulated glazing and other façade components. Thus, such buildings are vulnerable to power failures, mechanical system failures, and extended demand response strategies. Furthermore, such buildings can be uncomfortable and high in energy consumption during normal operation. This paper describes a methodology to evaluate building resilience using simulation methods. Several resilience metrics were developed or obtained from the literature including: thermal autonomy and passive survivability. A Toronto, Canada-based case study was performed to assess the effect of various passive design strategies to improve resilience. Results showed that thermal autonomy was very poor without occupant interaction. However, this did not translate to poor passive survivability; relatively comfortable conditions were maintained for at least two to three days after power failures.

We introduce and provide results from a rigorous, scientific testing methodology that allows pure building model calibration systems to be compared fairly to traditional output error (e.g. how well does simulation output match utility bills?) as well as input-side error (e.g. how well, variable-by-variable, did the calibration capture the true building's description?). This system is then used to generate data for a correlation study of output and input error measures that validates CV(RMSE) and NMBE metrics put forth by ASHRAE Guideline 14 and suggests possible alternatives.

Smart windows are used to reduce energy consumption and improve thermal and visual comfort by controlling the solar flux entering into a building and/or adapting their thermal resistances. A commercial building with integrated electrochromic windows is modeled. The hour-by-hour state of the smart windows required to minimize overall energy consumption (heating, cooling, lighting) while respecting constraints related to visual comfort is determined through an optimization strategy based on genetic algorithms. Then, this optimal control is compared to two other approaches that could be applied in real-time applications: (i) rule-based control, and (ii) predictive control. The impacts of thermal mass, façade orientation and climate are analyzed.

Accurate energy performance prediction of HVAC system plays a significant role for intelligent building operations to improve energy efficiency and reduce energy consumption in buildings. In modern commercial and residential buildings, large amounts of raw data, including electric metering data, are monitored, trended and saved in, for example, Building Automation System (BAS). Due to the complexity of building mechanical and electrical system and the cost, practically speaking, it is impossible to have sensors/meters to monitor the building at a fine granularity. Building total energy consumption (e.g., total electricity consumption) is one of the most commonly available metering data.

Many facility departments have installed energy meters seeking to pin point how, where and when energy is being inefficiently utilized. This has led to the recording of vast amount of data over extended periods of time, which makes it very difficult to manage and manually analyze. Luckily, techniques in machine learning have shown promising results in automated knowledge discovery making it more and more crucial when large data is at hand. This paper applies machine learning (ML) algorithms to detect abnormalities in chilled water systems (CWS) at building level. Two abnormal situations are pursued: chilled water sensor misreadings and low thermal efficiency in terms of delta T. The visualization of building chilled water historical data provides general trends and an initial identification of the building abnormalities; this visualization also helps to lay down the requirements for the abnormality detection algorithms, and eventually, their selection.

The accuracy of experimental results has always concerned engineers and scientists. The uncertainty of each parameter is desired to be minimized because these uncertainties will propagate in the data reduction process. In heat-transfer equipment testing, there are usually two independent measurements of heat-transfer rate in the hot and cold stream respectively (Q_h and Q_c). It is proposed in this paper that Q_ave should be calculated based on a form of weighted-linear average, with weighting factors depending on the individual uncertainties in Q_h and Q_c. Heat-transfer rate which has higher uncertainty will be weighed less in the average, and the other one with lower uncertainty will be weighed more accordingly. Implementing this new methodology will minimize the uncertainty in heat-transfer coefficient and Colburn j factors, which will consequently provide more accurate data for use in the development of correlations or for performance comparison purposes.