How energy efficient can commercial and multifamily buildings become in the near future if first cost is
not considered? This presentation describes how building energy simulation modeling was used to try to answer this question. The RP-1651 project involves; identifying advanced technologies to include in modeling of ultra-low energy targets, simulating maximum commercial building energy efficiency levels that are technically achievable now or in the near future by modeling using the DOE reference building models, simulating alternative scenarios examining the relative impact of groups of measures and finally, the energy savings results for the reference buildings and climates will be discussed.

This presentation provides an overview of the scope for RP-1651 and the reference building models that will be used in the analysis performed for RP-1651.  The reference buildings cover more than 80% of the commercial building stock including offices, retail, warehouse, healthcare, restaurant, apartments and schools.  Reference building models are based on Standard 90.1 and have been used to analyses the energy impacts of new versions of that standard. The models were developed for all 17 climate zones throughout the United States.

Specifics of EUI for buildings in Chicago were presented in Orlando. This presentation provides information on the energy components of the buildings.

Details of the Energy Use index from some selected buildings were presented in Orlando. This presentation will provide a more detailed breakdown of the buildings energy components.

The speaker introduces current situations and trends of energy use in Chinese rural buildings, followed by setting up a goal to achieve zero coal and low emission heating. He then addresses a subset of problems that are important to low emission heating in Chinese rural housing. These are the need to: improve the thermal integrity of rural housing; develop biomass utilization technologies for heating and cooking; develop solar energy utilization technologies for heating and hot water supply. Strategies for reducing the use of coal and CO₂ emissions in rural communities are discussed with demonstration projects.

While contemporary architects desire the integration of passive solar heating strategies into design concepts, energy performance is still difficult to predict due to the complexity of related physics. Few energy modeling tools provide passive solar heating because the selection of CFD turbulence models for buoyancy low velocity phenomena and solar radiation models remain a challenge. Utilizing the Interlock House, a 2009 US DOE Solar Decathlon home and Iowa NSF EPSCoR community lab our team conducted refined measurements of passive solar heating effects on a sunny day (March 8th, 2015) in order to validate new approaches to CFD model selection.

BPS aimed to minimize final energy loads has been done as a prerequisite to conduct deep energy refurbishment leading to the effective integration of solar energy. Identified moisture penetration in building envelope directed envelope structure to be changed to ventilated façade within refurbishment works (PV glazed second façade as the most appropriate concerning construction works and existing building structure statics). New façade cooling and heating loads and their dynamics for different levels of PV glazing’s transparency and different designs, regimes and uses of ventilation air are studied (encompassing Indoor space comfort, and outdoor air-wind influence CFD and co-simulation analysis).

Energy retrofits provide an economically attractive solution to reduce the carbon footprint of existing buildings. However, indoor environmental quality and occupant comfort are often overlooked in the retrofit process. In this paper, we present the results of pre-retrofit monitoring of several multi-unit residential buildings in Toronto, Canada. The temperature, relative humidity and mean radiant temperature were measured in over 70 units across seven social housing buildings (built between 1960 and 1980) currently undergoing an energy retrofit process. Occupant thermal comfort was estimated using the Graphic Comfort Zone Method outlined in ASHRAE Standard 55-2013 and excess moisture was calculated as the vapour pressure excess during non-air conditioning periods. The major finding was that on average, the units were uncomfortable more than 70% of the time, with overheating being the main cause of discomfort. Location within a building (e.g., upper vs. lower floors) and building-specific effects showed little impact, although there was a weak seasonal effect with more overheating in the winter and spring. These findings are consistent with an occupant survey taken early in the project.  There was no consistent evidence of excess moisture, although this may be due to the observed overheating in the units. The results were used to inform the energy retrofit design process and are currently being monitored to ascertain how the retrofits affect occupant comfort in these buildings.

Advances on manufacturing processes and the use of new materials are increasing the efficiency and reducing the cost of energy efficient and renewable energy technologies to a point that their deployment will reach desired levels for the sake of energy security and environmental concerns. Along these advances, the demonstration of the cost-effectiveness of this technology is vital to educate people and promote deployment of these technologies. In this sense, at the University of Texas at Tyler, two research and demonstration houses were built. House #1 is a conventional design with some advanced features, and House #2 has more advanced design features. In this study, House 2 is considered, which has relevant characteristics such as net-zero energy with 7.4 kW of solar photovoltaic system, advanced wall framing with open-cell foam insulation (R-24), unvented attic with open-cell foam insulated roof deck (R-24), vinyl-frame windows with double-pane, low-E glass (U=0.33, SHGF=0.23), ducted single-split system in attic (19.0 SEER, 9.0 HSPF), high solar reflectance shingles, and heat pump water heater. Since building energy performance depends on many factors, different scenarios or design characteristics can be assessed by using an energy model. In this study, the software OpenStudio is used to develop a model for House #2. OpenStudio, developed by the National Renewable Energy Laboratory, is a user interface for the well know whole building energy simulation engine EnergyPlus. This paper shows the more relevant steps on model development including definition of the constructions in the model for the walls and roof, development of performance curves for the air source heat pump installed in the house, roof elevations development technique, and weather file. As a means of validation of the model, energy consumption from the model is compared against utility bills data in a calibration approach that is available in the software. The model is used to evaluate some design parameter that can reduce energy consumption during one season (cooling or heating), but increasing energy consumption during the other, such as the high solar reflectance shingles and the use of a heat pump water heater.

This presentation explains the various methods high performance designers follow during high performance design process. It particularly focuses on the design methodology used in a 1740-ft (530m) supertall net zero building on a 3,450,000-ft² campus in the heart of Jakarta, Indonesia. Pertamina’s new headquarters and campus are a mixed use development for the 20,000 plus employees and visitors expected to work daily on the campus. Low enthalpy geothermal system in a combined heat and power scheme using binary cycle technology as primary source of energy will make Pertamina’s Energy Tower the tallest net-zero building in the world.

This presentation describes the role that Standard 189.1 plays in efforts by policymakers to achieve net zero energy and high performance green buildings.

This presentation describes the efforts in Europe to achieve net zero energy and high performance green buildings that have come as a result of the 2015 Paris Climate Agreement and related activities.

Before we know if a building has achieved Zero Net Energy (ZNE) status, we must know which metric is being used in the ZNE evaluation. The seminar presents the various metrics and their pros and cons being used in the ZNE definition from Site energy to Time Dependent Valuation energy and everything in between as well as their impact on the building systems design and energy code compliance.

Utilizing the Net Zero Plus Electrical Training Institute facility (one of the largest net zero commercial retrofits in the United States) as a dynamic case study, this presentation provides a roadmap to achieving zero net energy (ZNE) including discussion on the research, design strategies, and engineering processes that maximize energy efficiency and reduce consumption and costs. The presenter also discusses renewable energy systems and advanced technologies including microgrid systems paired with battery energy storage and measurement and verification (M&V) systems for achieving and maintaining ZNE status. Discussions also include various ZNE financing mechanisms and rebates.

Significant attention has been given to get residential new construction to reach zero net energy (ZNE) as already seen in many city (e.g. Austin), county (e.g., Tucson-Prima) and state (e.g., California) energy code requirements. This presentation focuses on retrofitting single-family homes to reach ZNE status. The presentation provides the results of retrofitting three blocks of homes with different levels of energy efficiency measures, demand response strategies, renewable energy systems, battery energy storage units, and electric vehicles charging stations in the quest to reach ZNE. The presentation also highlights potential electric grid impact of some of these technologies.

This presentation describes the often misunderstood processes by which code officials adopt, amend, and implement building energy codes and model standards such as the International Energy Conservation Code and Standard 90.1. Tips will also be provided for how ASHRAE members can become involved with these processes.

This presentation describes how ASHRAE members can effectively work with state energy officials to encourage the adoption and implementation of the most recent editions of the model building energy codes.

This session presents up-to-date theory and tools important in specifying low emissions high efficiency bio-thermal HVAC systems.  Hydronic distribution incorporating advanced heat storage technology and digital firing control stabilizes combustion, eliminates excess cycling, and prevents low-fire air emissions without overheating occupied spaces. Principles apply to all types of solid biomass fuel. Woody biomass is an inexpensive, widely available and renewable heat source.  By learning about equipment and processes  already in commercial service engineers will be able to specify wood-fired HVAC systems without  the risks, delays and extra cost of “re-inventing"

Sustainable renewability of woody biomass fuel is reviewed, in the context of energy uses with the greatest  thermal use efficiency and local sourcing potential.  Biothermal heat and cooling systems enabling Near-Net-Zero status implement advanced equipment, technologies and methods commercially applied with success around the world, but underutilized in North America. Topics covered: fuel (quantification, preventing known handling problems, and source sustainability) and factors enhancing economic and environmental potential: (non-electric cooling driven by renewable heat, low-cost tools to evaluate single and multi-building opportunities and optimizing thermal capacity to reduce capital cost.

Operating history is the most reliable tool for evaluating whether good ideas really worked in practice.  This segment provides that background for risk sensitive building energy designers considering the value potential and best practices to follow in specifying these emerging technologies. Results data is presented for facilities employing biothermal HVAC as commercial practice.  Functional reliability, convenience, compliance with air quality rules, electricity consumption, peak demand effects, economic performance compared with predictions and occupant satisfaction are addressed.  Efforts that were employed to build awareness about the advanced systems and increase their market penetration will be described.

Passive buildings must be designed with a number of specialized considerations on HVAC systems, including acoustic constraints, the use of ERVs, and the use of smaller amounts of ductwork.  This talk describes how these considerations are taken into account in practical building designs.

VRF systems are ideally suited to application in passive buildings and homes, due to their high part-load energy efficiency, low fan noise, and flexibility in installation.  This presentation provides new information about the application of these systems to ultra-low-energy buildings, as well as measured data on performance of these systems in the field.

This presentation reviews the load calculation process for ultra-low energy buildings, the selection of equipment and design of systems, and (hopefully!) present monitored energy & comfort data.

Winner of the 2015 US Dept of Energy Solar Decathlon, The Stevens Institute of Technology's SURE HOUSE is a residential prototype for a truly sustainable and resilient home for the New Jersey shore. This student-designed and -built home uses 90% less energy than a typical New Jersey home through Passive House measures, is flood-proofed using a high-performance plastic and fiber-composite protective shell, and is fully solar powered. These measures combine to create a home which seeks to reduce its contribution to global climate change while also bracing for the effects of rising sea levels and increasingly severe storms.

Nexushaus is a new residential housing prototype that is responsive to the challenges of the energy-water “nexus” in the context of growth in the United States from Texas all the way west to California. Nexushaus offers residents the following features: A modular design system that can change as residents’ needs change over time, smaller, well designed interior spaces combined with generous outdoor living spaces, a photovoltaic array designed for maximum efficiency and flexibility, a hydronic air conditioning and heating system, a potable rainwater collection system with integrated thermal storage and a greywater garden irrigation system.

This paper presents the energy efficiency, cost effectiveness and development potential of a new energy supply concept. The concept is based on solar hybrid, bore hole heat storage and a ground source heat pump. The back of the photovoltaic cells is cooled with cold water to increase the efficiency. The heated water is then connected to the cold side of a ground-source heat pump (GSHP) and to bore holes. The heat from the solar hybrid can be used in several ways to increase the efficiency of the heat pump, e.g. as the direct source of heat or to recharge the bore holes. A housing association consistent of 70 terraced houses on the west coast of Sweden has installed this new system solution. The system consists of 337 m²solar hybrid panels mounted on the roof of the terraced houses, and GSHP with seven bore holes. During the year of 2015 detailed measurements on this full scaled system is performed. In this paper presents the results from these measurements, as well as analysis of the data. The analysis aims to quantify the energy efficiency of the system. The first results show that the system has a good efficiency and that the energy demand has decreased significantly. The monitoring has also been used as a tool to adjust the system and optimize the system solution. After only a few months of monitoring adjustments advices for improvements of the regulation strategies were suggested and implemented. These changes have led to a system that is now even more efficient than at the initial installation. In parallel to the monitoring the experiences from the housing association is investigated through interviews and enquiries. In the paper their perception of common ownership, obstacles in the implementation and advices on procurement will be presented. The paper aims to increase the knowledge about this system solution with solar hybrid and geothermal combined. The increased knowledge will eventually lead to a broader implementation of this system solution with 100 % renewables.

In Canada, outside air temperatures can vary significantly during the year. A temperature gradient of 70 ⁰C between the cooling and heating season is common in many regions. Because of the high thermal inertia of the soil, airflow circulating in earth tubes will benefit of  a significant temperature increase or decrease with respect to heating or cooling season . The advantages of an earth-to-air heat exchange system are its simplicity, high pre-cooling and pre-heating potential leading to fossil fuel savings and related emisssions and low operation maintenance costs. Very few experimental studies of ground temperature impact on heating with earth-to-air heat exchanger were found in the literature for cold climate. This paper deals with the performance of an earth-to-air heat exchange system for an operational Canadian building, with the aim of characterizing its efficiency. The building, called Earth Rangers, is a visitors’ centre built to educate children about biodiversity, conservation and the adoption of more sustainable behaviors. The earth tube system is an earth-to-air heat exchanger system which consists of nine 900 mm diameter, 20 m long pre-cast concrete pipes buried beneath the frost line (approximately 1500 mm below grade). Outside air is drawn through the buried concrete pipes allowing surrounding earth to moderate the temperature of the incoming air so that it is either pre-heated or pre-cooled depending on the time of year. The performance assessment of the earth tube system consisted of continuous monitoring between January and November 2014.Results from winter and summer field monitoring are presented in terms of overall heat exchanger effectiveness and comparing the pre-heating effectiveness of the  monitored earth tubes and exploring what could be done to improve the design. This long-term field study on earth tubes has confirmed the overall effectiveness of this passive means during the winter and summer conditions.

At the technical University of Denmark, research in energy balance in buildings in relation to indoor climate has been performed with good results for decades. During the last 2 decades, research in the field of Integrated Energy Design (IED) focusing on the earliest design phases has played a major role. Research demonstrate that the largest effect in relation achieving net zero energy buildings is obtained when indoor climate and energy simulation tools are applied from the first architectural sketches, where geometry, façade design  and orientation etc.  is determined. Large architectural offices and engineering consultancies in the region have invested in software and interdisciplinary design teams and perform Integrated Energy Design (IED). Legislation has been altered; Simulations of indoor climate and energy balance is required in order to obtain building permits. IED has been rolled out extensively in the building industry. Having reduced the energy needed to operate the indoor environment to almost zero, by designing with knowledge and optimizing systems, the energy needed to construct the building and its systems comes forth as important.  The CO2 impact of buildings becomes an important parameter because sustainability certification systems like Deutche Gesellschaft für Nachhaltiges Bauen (DGNB) has taken a lead in Europe. The DGNB system includes Life Cycle Assesment (LCA) and Danish government has stated that Denmark must be CO2 neutral by 2050. The focus shifts from energy and indoor climate to CO2 impact in relation to design. The experience from the decades of IED manifests, that the largest gain in reduction stems from the early design phases. LCA in relation to buildings has to include the energy needed to operate the buildings indoor climate as well as embodied CO2 in the building.  This makes the simulations far more complex. LCA thus tends to be placed in the last design phases and used for evaluation: only a single iteration is needed. However real-time LCA simulation tools are required, if designers are to base design decisions on not only knowledge concerning indoor climate and energy balance but also LCA. The paper presents the efforts at DTU, Department of civil engineering, to develop  real-time LCA simulation tools including indoor climate and energy balance simulation (based on Energy +) and first round of implementing the tool at well esteemed architectural offices in the Nordic Countries. The development of the real-time LCA-indoor climate- energy balance tool was developed by funding from the Nordic Built Foundation.

This paper presents methodology of study of the synergetic energy/environment’s constrains relevant to the residential buildings settlement’s sustainability. Presented are results of the design of a sustainable Net Zero Energy Buildings Settlement. Implementing integrated building design building’s dynamic behavior and energy efficiency have been optimized by the BPS resulting in crucial reduction of loads of the initial designs. Further multidisciplinary engineering optimization lead to the settlement of NZEB status (HVAC system’s heat pumps using sea water, and other building’s technical systems powered exclusively by RES (solar thermal, PV, wind and biomass), and water recycling bio-aquatic water treatment are closing the village eco-sustainability.

The European Directive on the Energy Performance in Buildings (EPBD) mandates nearly-zero energy new buildings by 2020. This presentation reviews characteristics and benchmarks of NZEBs from within existing building stock. A European-developed framework for assessing residential building refurbishment is presented based on regional/national building typologies for large building portfolios. This procedure enables key experts/non-experts to ensure high-quality retrofits, check regulatory compliance, track/steer refurbishment processes and quantify energy savings. The presentation concludes with results of future EU Member State refurbishment strategies to make realistic projections of residential heating energy use and support efforts for meeting energy savings or emissions targets.

It all starts with a holistic approach from the ground up with the aim to first, reduce our home energy consumption by installing high performance building envelope, including but not limited to double glazed windows with low emissivity, better insulation that exceeds minimum building energy code, use of high efficiency appliances and HVAC equipment. And second, install solar electric (PV) and thermal systems to handle the remaining annual energy requirement. High performance building envelope combined with high efficiency appliances and equipment, and integration of solar energy systems can lead our homes to become NZEB. A case study is discussed.

To achieve zero net energy in residential dwellings, a roof mounted PV system is typically the enabling technology at the center of the energy design.  This presentation explores financing models and trends for the U.S. residential PV market.  Third-party power purchase agreements (PPAs) and lease based financing in the solar industry is less than a decade old, but they are rapidly becoming the dominant PV system delivery methods.  The PPA model faces regulatory and legislative challenges in some states.  These issues are presented and discussed with a look forward toward future developments.