Joshua Kneifel - Profile on Academia.edu (original) (raw)

Papers by Joshua Kneifel

Due to the significant life-safety and economic loss resulting from extreme, "low probability, hi... more Due to the significant life-safety and economic loss resulting from extreme, "low probability, high consequence" weather events such as Hurricane Katrina, Hurricane Sandy, and the Joplin tornado, greater focus has been placed on increasing the resiliency of buildings to decrease these impacts. Investigations of building performance following tornadoes and hurricanes have shown that wind-borne debris, including loose aggregate, gravel, and stone surfacing on roofs are significant contributors to building damage and occupant injuries. Buildings may often experience little to no structural damage, but suffer failure of exterior glazing, causing catastrophic damage to building interiors and building contents that can also result in injuries and fatalities. A recent proposed code change to the International Building Code (IBC) would prohibit installation of loose aggregate surfacing on roofs of Risk Category III or IV buildings located in the most tornado-prone region of the country (covering portions of the Great Plains, Midwest, and Deep South) in order to reduce the wind-borne debris hazard, particularly to glazed openings.

Homeowners and builders have increasingly strived to build low energy homes. As building material... more Homeowners and builders have increasingly strived to build low energy homes. As building materials, equipment, and methods have improved and renewable energy systems have become commonplace, the goal of net-zero energy homes has become technologically viable. Such an example of these capabilities is on display in the Net-Zero Energy Residential Test Facility (NZERTF), located at the National Institute of Standards and Technology (NIST) in Gaithersburg, Maryland. While the NIST NZERTF has shown that net-zero energy performing homes are technologically feasible using conventional technologies, questions related to costs continue to arise. Economic performance evaluation is reliant on accurate construction cost data, which may change significantly over time as industry learns how to implement energy-efficiency measures into building design and more energy-efficient technology diffuses into the marketplace. In order to update the underlying data in NIST's economic analysis, a NIST-funded contract was completed to estimate the costs of building components designed to meet current Maryland building energy code based on 2015 IECC as well as higher efficiency building components that are either currently installed in the NZERTF or will be installed in the NZERTF in the near future.

Energy efficiency requirements in energy codes for residential buildings vary across states, and ... more Energy efficiency requirements in energy codes for residential buildings vary across states, and many states have not yet adopted the latest energy efficiency code edition. As of July 2014, states had adopted energy codes ranging across editions of the International Energy Conservation Code (IECC) (2003, 2006, 2009, and 2012). Some states do not have a code requirement for energy efficiency, leaving it up to the locality or jurisdiction to set its own requirements. This study considers the impacts that the adoption of newer, more stringent energy codes for residential buildings would have on building energy use, operational energy costs, building life-cycle costs, and “cradle-to-grave” life-cycle carbon emissions. The results of this report are based on analysis of the Building Industry Reporting and Design for Sustainability (BIRDS) new residential database, which includes 9120 whole building energy simulations covering 10 building types in 228 cities across all U.S. states for study periods ranging from 1 year to 40 years. The performance of buildings designed to meet current state energy codes is compared to their performance when meeting new editions of IECC design requirements to determine whether more stringent energy code editions are cost-effective in reducing energy consumption and life-cycle carbon emissions. The estimated savings for each of the building types are aggregated using city- level new residential building construction data to calculate the magnitude of the incremental savings that a state may realize if it were to adopt a more energy efficient code edition as its state energy code. These state-level estimates are further aggregated to the national level to estimate the potential total impact from nationwide adoption of more stringent energy codes.

Building stakeholders need practical metrics, data, and tools to support decisions related to sus... more Building stakeholders need practical metrics, data, and tools to support decisions related to sustainable building designs, technologies, standards, and codes. The Engineering Laboratory of the National Institute of Standards and Technology (NIST) has addressed this high priority national need by extending its metrics and tools for sustainable building products, known as Building for Environmental and Economic Sustainability (BEES), to whole-buildings. Wholebuilding sustainability metrics have been developed based on innovative extensions to life-cycle assessment (LCA) and life-cycle costing (LCC) approaches involving whole-building energy simulations. The measurement system evaluates the sustainability of both the materials and the energy used by a building over time. It assesses the "carbon footprint" of buildings as well as 11 other environmental performance metrics, and integrates economic performance metrics to yield science-based measures of the business case for investment choices in high-performance green buildings.

Previous studies have shown that mature shade trees can reduce total energy use in residential ho... more Previous studies have shown that mature shade trees can reduce total energy use in residential homes in a life-cycle cost effective manner, particularly when located on the west side of a building. However, no study has precisely determined the optimal location for a shade tree, nor has the dynamic impact of the year-by-year growth of shade trees been studied. This research develops a basic method to determine the optimal locations of shade trees and compares results from six case-studies to evaluate whether the impact of shade trees varies across the United States. Building energy consumption is simulated for a prototypical residential structure over a 20-year time period after the planting of a twoyear old shade tree sapling. Simulations are performed for six cities representative of five different climate zones. Overall energy reductions and life-cycle cost savings are found to vary over time and to a lesser, but similar extent between cities. Planting a shade tree is generally not cost-effective for a homeowner in the first 10 years, but is costeffective over a 20-year time period. Given that electric utilities desire to reduce longterm peak electricity demand, the life-cycle cost results support the benefits of utilitysupported shade tree programs.

Some states do not have a code requirement for energy efficiency, leaving it up to the locality o... more Some states do not have a code requirement for energy efficiency, leaving it up to the locality or jurisdiction to set its own requirements. This study considers the impacts that the adoption of newer, more stringent energy codes for commercial buildings would have on building energy use, operational energy costs, building life-cycle costs, and cradle-to-grave energy-related carbon emissions.

Energy efficiency requirements in current commercial building energy codes vary across states. En... more Energy efficiency requirements in current commercial building energy codes vary across states. Energy standards that are currently adopted by states range from ASHRAE 90. 1-19991- to ASHRAE 90.1-2007. Some states do not have a code requirement for energy efficiency, leaving it up to the locality or jurisdiction to set their own requirements. The six National Institute of Standards and Technology (NIST) Special Publications (1147, 1148-1, 1148-2, 1148-3, and 1148-4) use the Building Industry Reporting and Design for Sustainability (BIRDS) database to analyze the impacts that the adoption of newer, more efficient commercial building energy codes would have on building energy use, operational energy costs, building life-cycle costs, and energy-related carbon emissions for each state by Census Region. This study summarizes the results from the series of documents for each of the 50 states into a two-page section.

The National Institute of Standards and Technology (NIST) received funding through the American R... more The National Institute of Standards and Technology (NIST) received funding through the American Recovery and Reinvestment Act (ARRA) to construct a Net Zero Energy Residential Test Facility (NZERTF). The initial goal of the NZERTF is to demonstrate that a net-zero energy residential design can "look and feel" like a typical home in the Gaithersburg area. The demonstration phase of the project intends to demonstrate that the operation of the house does perform at "net zero," or produces as much electricity as it consumes over an entire year. The NZERTF began the demonstration phase in July 2013 and will be completed in June 2014.

Energy efficiency requirements in energy codes vary across states, with states having adopted ene... more Energy efficiency requirements in energy codes vary across states, with states having adopted energy codes ranging across editions of the industry consensus standard (ASHRAE 90.1). Some states do not have a code requirement for energy efficiency, leaving it up to the locality or jurisdiction to set its own requirements. This paper uses ASTM building economic standards (E917-05(2010) and E1074-09) to estimate the impacts that the adoption of more stringent energy codes for commercial buildings would have on building life-cycle costs. The results are based on analysis of the Building Industry Reporting and Design for Sustainability (BIRDS) database. For this study, the performance of buildings designed to meet current state energy codes is compared to their performance when meeting a "Low Energy Case" (LEC) building design based on ASHRAE 189.1-2009, which increases energy efficiency beyond the ASHRAE 90.1-2007 design, to determine whether more stringent energy standard editions are life-cycle cost-effective in reducing energy consumption. The approach is described in detail for a single city and building type (Knoxville, TN). Using the same approach, the new savings for each building type in all cities for Tennessee are calculated. The estimated average savings for each of the building types are aggregated using state-level new commercial building construction data to calculate the magnitude of the net savings (80.8 GWh annually and 28.1millioninlife−cyclecosts)thatTennesseemayrealizeifitweretoadopttheLECdesignasitsstateenergycode.Thesestate−levelestimatesarefurtheraggregatedtothenationallevel,estimatingthepotentialtotalimpactfromnationwideadoptionoftheLECdesigntobe34441GWhand28.1 million in life-cycle costs) that Tennessee may realize if it were to adopt the LEC design as its state energy code. These state-level estimates are further aggregated to the national level, estimating the potential total impact from nationwide adoption of the LEC design to be 34 441 GWh and 28.1millioninlife−cyclecosts)thatTennesseemayrealizeifitweretoadopttheLECdesignasitsstateenergycode.Thesestate−levelestimatesarefurtheraggregatedtothenationallevel,estimatingthepotentialtotalimpactfromnationwideadoptionoftheLECdesigntobe34441GWhand1.0 billion for one year's worth of construction for a 10-year study period.

Price (Cents/kWh) 0.0 to 9.0 9.0 to 11.0 11.0 to 13.0 13.0 to 15.0 15.0 to 17.0 17.0 to 41.9

The Applied Economics Office (AEO) of the Engineering Laboratory (EL) at the National Institute o... more The Applied Economics Office (AEO) of the Engineering Laboratory (EL) at the National Institute of Standards and Technology (NIST) has developed the Building Industry Reporting and Design for Sustainability (BIRDS) database, which estimates the sustainability (energy, economic, and environmental) performance for eleven commercial building prototypes designed to different energy efficiency levels. Analysis of the BIRDS database estimates both the average percentage change in energy consumption and the aggregate changes in energy consumption for one year's worth of new construction for each U.S. state. Due to the limited publically-available new construction data, the estimates are calculated by giving equal weighting to all the cities in a state that are included in the BIRDS database. However, such an approach leads to underweighting the importance of cities with more new construction and overweighting cities with less new construction.

Building stakeholders need practical metrics, data, and tools to support decisions related to sus... more Building stakeholders need practical metrics, data, and tools to support decisions related to sustainable building designs, technologies, standards, and codes. The Engineering Laboratory of the National Institute of Standards and Technology (NIST) has addressed this high priority national need by extending its metrics and tool for sustainable building products, known as Building for Environmental and Economic Sustainability (BEES), to whole buildings. Whole building sustainability metrics have been developed based on innovative extensions to life-cycle assessment (LCA) and life-cycle costing (LCC) approaches involving building energy simulations. The measurement system evaluates the sustainability of both the materials and the energy used by a building over time. It assesses the "carbon footprint" of buildings as well as 11 other environmental performance metrics, and integrates economic performance metrics to yield sciencebased measures of the business case for investment choices in high-performance green buildings.

The National Institute of Standards and Technology (NIST) received funding through the American R... more The National Institute of Standards and Technology (NIST) received funding through the American Recovery and Reinvestment Act (ARRA) to construct the Net-Zero Energy Residential Test Facility (NZERTF). One of the goals of the NZERTF is to demonstrate that a net-zero residential design can "look and feel" like a typical home in the Gaithersburg, MD area. There has been limited evaluation to date on the use of wholebuilding simulation models to evaluate the sensitivity of a unique net-zero energy building design's energy performance to varying weather conditions across multiple locations. Whole-building simulation software such as EnergyPlus (E+), allows the user to simulate the annual energy performance for a specific building design. The purpose of this report is to evaluate both the energy and economic performance of the NZERTF across the Building America Mixed-Humid Climate Zone, using the results of E+. Additionally, the NZERTF design is compared to code compliant designs for 45 locations throughout the climate zone.

This paper looks to contribute to the existing building simulation literature by examining the im... more This paper looks to contribute to the existing building simulation literature by examining the impacts of weather variability on annual household energy use and solar photovoltaic (PV) production for low-energy homes integrating renewable energy generation system(s) in their design. Using the U.S. Department of Energy's EnergyPlus v8.3 whole-building energy simulation program, we observe variability in the energy performance of a net-zero home across 34 different Actual Meteorological Year (AMY) weather files collected between 1980 and 2013 (U.S. Department of Energy (DOE) 2015). The simulated building design is based on the Net Zero Energy Residential Test Facility (NZERTF) developed by the National Institute of Standards and Technology. In addition to this, the simulation will be run with a local TMY3 weather file to evaluate how representative it is of "typical" weather conditions for the area, and if its use will result in accurate predictions of NZERTF energy performance.

The U.S. housing market has witnessed a rise in the number of low-energy and net-zero energy buil... more The U.S. housing market has witnessed a rise in the number of low-energy and net-zero energy buildings. Many of them integrate solar photovoltaic (PV) systems to reduce their electricity usage. In predicting the energy performance of a building design and the integrated PV system, builders utilize whole-building simulation programs. These programs either lack consideration of degradation, or are not explicit in the underlying assumptions of the model being used. In our analysis, we use the U.S. Department of Energy's Energy Plus (E+) Whole-building Energy Simulation program, along with alternative degradation model assumptions, to assess the impacts of system degradation on the energy and economic performance of the NIST Net-Zero Residential Test Facility (NZERTF). Alternative degradation rates and models are evaluated to understand the implications of alternative assumptions on system performance and economic viability. The performance sensitivity is compared to the sensitivity of the cost assumption parameters to determine the relative importance of solar PV degradation to the decision-making process.

Residential building energy efficiency is becoming increasingly important in U.S. energy policy. ... more Residential building energy efficiency is becoming increasingly important in U.S. energy policy. Analyzing the effectiveness of potential energy efficiency improvements in the residential sector involves running whole building energy simulations for alternative building designs. Such analysis requires detailed building design characteristics including climate, fuel type, energy technologies, and design improvements. For broad studies of the U.S. residential sector, prototypical designs representing "typical" residential buildings are necessary to provide the basis for this detailed analysis.

Building stakeholders need practical metrics, data, and tools to support decisions related to sus... more Building stakeholders need practical metrics, data, and tools to support decisions related to sustainable building designs, technologies, standards, and codes. The Engineering Laboratory of the National Institute of Standards and Technology (NIST) has addressed this high priority national need by extending its metrics and tools for sustainable building products, known as Building for Environmental and Economic Sustainability (BEES), to whole buildings. Whole building sustainability metrics have been developed based on innovative extensions to life-cycle assessment (LCA) and life-cycle costing (LCC) approaches involving whole building energy simulations. The measurement system evaluates the sustainability of both the materials and the energy used by a building over time. It assesses the "carbon footprint" of buildings as well as 11 other environmental performance metrics, and integrates economic performance metrics to yield science-based measures of the business case for investment choices in high-performance green buildings.

The National Institute of Standards and Technology (NIST) received funding through the American R... more The National Institute of Standards and Technology (NIST) received funding through the American Recovery and Reinvestment Act (ARRA) to construct a Net Zero Energy Residential Test Facility (NZERTF). The initial goal of the NZERTF is to demonstrate that a net-zero energy residential design can "look and feel" like a typical home in the Gaithersburg area. Demonstration phase of the project intends to demonstrate that the operation of the house does perform at "net zero," or produces as much electricity as it consumes over an entire year. The NZERTF is scheduled to begin the demonstration phase in 2013.

Energy efficiency requirements in energy codes for commercial buildings vary across states, and m... more Energy efficiency requirements in energy codes for commercial buildings vary across states, and many states have not yet adopted the latest energy efficiency standard edition. ). Some states do not have a code requirement for energy efficiency, leaving it up to the locality or jurisdiction to set its own requirements. This study considers the impacts that the adoption of newer, more stringent energy codes for commercial buildings would have on building energy use, operational energy costs, building life-cycle costs, and cradle-to-grave energy-related carbon emissions.

Energy efficiency requirements in energy codes for commercial buildings vary across states, and m... more Energy efficiency requirements in energy codes for commercial buildings vary across states, and many states have not yet adopted the latest energy efficiency standard edition. ). Some states do not have a code requirement for energy efficiency, leaving it up to the locality or jurisdiction to set its own requirements. This study considers the impacts that the adoption of newer, more stringent energy codes for commercial buildings would have on building energy use, operational energy costs, building life-cycle costs, and cradle-to-grave energy-related carbon emissions.

Due to the significant life-safety and economic loss resulting from extreme, "low probability, hi... more Due to the significant life-safety and economic loss resulting from extreme, "low probability, high consequence" weather events such as Hurricane Katrina, Hurricane Sandy, and the Joplin tornado, greater focus has been placed on increasing the resiliency of buildings to decrease these impacts. Investigations of building performance following tornadoes and hurricanes have shown that wind-borne debris, including loose aggregate, gravel, and stone surfacing on roofs are significant contributors to building damage and occupant injuries. Buildings may often experience little to no structural damage, but suffer failure of exterior glazing, causing catastrophic damage to building interiors and building contents that can also result in injuries and fatalities. A recent proposed code change to the International Building Code (IBC) would prohibit installation of loose aggregate surfacing on roofs of Risk Category III or IV buildings located in the most tornado-prone region of the country (covering portions of the Great Plains, Midwest, and Deep South) in order to reduce the wind-borne debris hazard, particularly to glazed openings.

Homeowners and builders have increasingly strived to build low energy homes. As building material... more Homeowners and builders have increasingly strived to build low energy homes. As building materials, equipment, and methods have improved and renewable energy systems have become commonplace, the goal of net-zero energy homes has become technologically viable. Such an example of these capabilities is on display in the Net-Zero Energy Residential Test Facility (NZERTF), located at the National Institute of Standards and Technology (NIST) in Gaithersburg, Maryland. While the NIST NZERTF has shown that net-zero energy performing homes are technologically feasible using conventional technologies, questions related to costs continue to arise. Economic performance evaluation is reliant on accurate construction cost data, which may change significantly over time as industry learns how to implement energy-efficiency measures into building design and more energy-efficient technology diffuses into the marketplace. In order to update the underlying data in NIST's economic analysis, a NIST-funded contract was completed to estimate the costs of building components designed to meet current Maryland building energy code based on 2015 IECC as well as higher efficiency building components that are either currently installed in the NZERTF or will be installed in the NZERTF in the near future.

Energy efficiency requirements in energy codes for residential buildings vary across states, and ... more Energy efficiency requirements in energy codes for residential buildings vary across states, and many states have not yet adopted the latest energy efficiency code edition. As of July 2014, states had adopted energy codes ranging across editions of the International Energy Conservation Code (IECC) (2003, 2006, 2009, and 2012). Some states do not have a code requirement for energy efficiency, leaving it up to the locality or jurisdiction to set its own requirements. This study considers the impacts that the adoption of newer, more stringent energy codes for residential buildings would have on building energy use, operational energy costs, building life-cycle costs, and “cradle-to-grave” life-cycle carbon emissions. The results of this report are based on analysis of the Building Industry Reporting and Design for Sustainability (BIRDS) new residential database, which includes 9120 whole building energy simulations covering 10 building types in 228 cities across all U.S. states for study periods ranging from 1 year to 40 years. The performance of buildings designed to meet current state energy codes is compared to their performance when meeting new editions of IECC design requirements to determine whether more stringent energy code editions are cost-effective in reducing energy consumption and life-cycle carbon emissions. The estimated savings for each of the building types are aggregated using city- level new residential building construction data to calculate the magnitude of the incremental savings that a state may realize if it were to adopt a more energy efficient code edition as its state energy code. These state-level estimates are further aggregated to the national level to estimate the potential total impact from nationwide adoption of more stringent energy codes.

Building stakeholders need practical metrics, data, and tools to support decisions related to sus... more Building stakeholders need practical metrics, data, and tools to support decisions related to sustainable building designs, technologies, standards, and codes. The Engineering Laboratory of the National Institute of Standards and Technology (NIST) has addressed this high priority national need by extending its metrics and tools for sustainable building products, known as Building for Environmental and Economic Sustainability (BEES), to whole-buildings. Wholebuilding sustainability metrics have been developed based on innovative extensions to life-cycle assessment (LCA) and life-cycle costing (LCC) approaches involving whole-building energy simulations. The measurement system evaluates the sustainability of both the materials and the energy used by a building over time. It assesses the "carbon footprint" of buildings as well as 11 other environmental performance metrics, and integrates economic performance metrics to yield science-based measures of the business case for investment choices in high-performance green buildings.

Previous studies have shown that mature shade trees can reduce total energy use in residential ho... more Previous studies have shown that mature shade trees can reduce total energy use in residential homes in a life-cycle cost effective manner, particularly when located on the west side of a building. However, no study has precisely determined the optimal location for a shade tree, nor has the dynamic impact of the year-by-year growth of shade trees been studied. This research develops a basic method to determine the optimal locations of shade trees and compares results from six case-studies to evaluate whether the impact of shade trees varies across the United States. Building energy consumption is simulated for a prototypical residential structure over a 20-year time period after the planting of a twoyear old shade tree sapling. Simulations are performed for six cities representative of five different climate zones. Overall energy reductions and life-cycle cost savings are found to vary over time and to a lesser, but similar extent between cities. Planting a shade tree is generally not cost-effective for a homeowner in the first 10 years, but is costeffective over a 20-year time period. Given that electric utilities desire to reduce longterm peak electricity demand, the life-cycle cost results support the benefits of utilitysupported shade tree programs.

Some states do not have a code requirement for energy efficiency, leaving it up to the locality o... more Some states do not have a code requirement for energy efficiency, leaving it up to the locality or jurisdiction to set its own requirements. This study considers the impacts that the adoption of newer, more stringent energy codes for commercial buildings would have on building energy use, operational energy costs, building life-cycle costs, and cradle-to-grave energy-related carbon emissions.

Energy efficiency requirements in current commercial building energy codes vary across states. En... more Energy efficiency requirements in current commercial building energy codes vary across states. Energy standards that are currently adopted by states range from ASHRAE 90. 1-19991- to ASHRAE 90.1-2007. Some states do not have a code requirement for energy efficiency, leaving it up to the locality or jurisdiction to set their own requirements. The six National Institute of Standards and Technology (NIST) Special Publications (1147, 1148-1, 1148-2, 1148-3, and 1148-4) use the Building Industry Reporting and Design for Sustainability (BIRDS) database to analyze the impacts that the adoption of newer, more efficient commercial building energy codes would have on building energy use, operational energy costs, building life-cycle costs, and energy-related carbon emissions for each state by Census Region. This study summarizes the results from the series of documents for each of the 50 states into a two-page section.

The National Institute of Standards and Technology (NIST) received funding through the American R... more The National Institute of Standards and Technology (NIST) received funding through the American Recovery and Reinvestment Act (ARRA) to construct a Net Zero Energy Residential Test Facility (NZERTF). The initial goal of the NZERTF is to demonstrate that a net-zero energy residential design can "look and feel" like a typical home in the Gaithersburg area. The demonstration phase of the project intends to demonstrate that the operation of the house does perform at "net zero," or produces as much electricity as it consumes over an entire year. The NZERTF began the demonstration phase in July 2013 and will be completed in June 2014.

Energy efficiency requirements in energy codes vary across states, with states having adopted ene... more Energy efficiency requirements in energy codes vary across states, with states having adopted energy codes ranging across editions of the industry consensus standard (ASHRAE 90.1). Some states do not have a code requirement for energy efficiency, leaving it up to the locality or jurisdiction to set its own requirements. This paper uses ASTM building economic standards (E917-05(2010) and E1074-09) to estimate the impacts that the adoption of more stringent energy codes for commercial buildings would have on building life-cycle costs. The results are based on analysis of the Building Industry Reporting and Design for Sustainability (BIRDS) database. For this study, the performance of buildings designed to meet current state energy codes is compared to their performance when meeting a "Low Energy Case" (LEC) building design based on ASHRAE 189.1-2009, which increases energy efficiency beyond the ASHRAE 90.1-2007 design, to determine whether more stringent energy standard editions are life-cycle cost-effective in reducing energy consumption. The approach is described in detail for a single city and building type (Knoxville, TN). Using the same approach, the new savings for each building type in all cities for Tennessee are calculated. The estimated average savings for each of the building types are aggregated using state-level new commercial building construction data to calculate the magnitude of the net savings (80.8 GWh annually and 28.1millioninlife−cyclecosts)thatTennesseemayrealizeifitweretoadopttheLECdesignasitsstateenergycode.Thesestate−levelestimatesarefurtheraggregatedtothenationallevel,estimatingthepotentialtotalimpactfromnationwideadoptionoftheLECdesigntobe34441GWhand28.1 million in life-cycle costs) that Tennessee may realize if it were to adopt the LEC design as its state energy code. These state-level estimates are further aggregated to the national level, estimating the potential total impact from nationwide adoption of the LEC design to be 34 441 GWh and 28.1millioninlife−cyclecosts)thatTennesseemayrealizeifitweretoadopttheLECdesignasitsstateenergycode.Thesestate−levelestimatesarefurtheraggregatedtothenationallevel,estimatingthepotentialtotalimpactfromnationwideadoptionoftheLECdesigntobe34441GWhand1.0 billion for one year's worth of construction for a 10-year study period.

Price (Cents/kWh) 0.0 to 9.0 9.0 to 11.0 11.0 to 13.0 13.0 to 15.0 15.0 to 17.0 17.0 to 41.9

The Applied Economics Office (AEO) of the Engineering Laboratory (EL) at the National Institute o... more The Applied Economics Office (AEO) of the Engineering Laboratory (EL) at the National Institute of Standards and Technology (NIST) has developed the Building Industry Reporting and Design for Sustainability (BIRDS) database, which estimates the sustainability (energy, economic, and environmental) performance for eleven commercial building prototypes designed to different energy efficiency levels. Analysis of the BIRDS database estimates both the average percentage change in energy consumption and the aggregate changes in energy consumption for one year's worth of new construction for each U.S. state. Due to the limited publically-available new construction data, the estimates are calculated by giving equal weighting to all the cities in a state that are included in the BIRDS database. However, such an approach leads to underweighting the importance of cities with more new construction and overweighting cities with less new construction.

Building stakeholders need practical metrics, data, and tools to support decisions related to sus... more Building stakeholders need practical metrics, data, and tools to support decisions related to sustainable building designs, technologies, standards, and codes. The Engineering Laboratory of the National Institute of Standards and Technology (NIST) has addressed this high priority national need by extending its metrics and tool for sustainable building products, known as Building for Environmental and Economic Sustainability (BEES), to whole buildings. Whole building sustainability metrics have been developed based on innovative extensions to life-cycle assessment (LCA) and life-cycle costing (LCC) approaches involving building energy simulations. The measurement system evaluates the sustainability of both the materials and the energy used by a building over time. It assesses the "carbon footprint" of buildings as well as 11 other environmental performance metrics, and integrates economic performance metrics to yield sciencebased measures of the business case for investment choices in high-performance green buildings.

The National Institute of Standards and Technology (NIST) received funding through the American R... more The National Institute of Standards and Technology (NIST) received funding through the American Recovery and Reinvestment Act (ARRA) to construct the Net-Zero Energy Residential Test Facility (NZERTF). One of the goals of the NZERTF is to demonstrate that a net-zero residential design can "look and feel" like a typical home in the Gaithersburg, MD area. There has been limited evaluation to date on the use of wholebuilding simulation models to evaluate the sensitivity of a unique net-zero energy building design's energy performance to varying weather conditions across multiple locations. Whole-building simulation software such as EnergyPlus (E+), allows the user to simulate the annual energy performance for a specific building design. The purpose of this report is to evaluate both the energy and economic performance of the NZERTF across the Building America Mixed-Humid Climate Zone, using the results of E+. Additionally, the NZERTF design is compared to code compliant designs for 45 locations throughout the climate zone.

This paper looks to contribute to the existing building simulation literature by examining the im... more This paper looks to contribute to the existing building simulation literature by examining the impacts of weather variability on annual household energy use and solar photovoltaic (PV) production for low-energy homes integrating renewable energy generation system(s) in their design. Using the U.S. Department of Energy's EnergyPlus v8.3 whole-building energy simulation program, we observe variability in the energy performance of a net-zero home across 34 different Actual Meteorological Year (AMY) weather files collected between 1980 and 2013 (U.S. Department of Energy (DOE) 2015). The simulated building design is based on the Net Zero Energy Residential Test Facility (NZERTF) developed by the National Institute of Standards and Technology. In addition to this, the simulation will be run with a local TMY3 weather file to evaluate how representative it is of "typical" weather conditions for the area, and if its use will result in accurate predictions of NZERTF energy performance.

The U.S. housing market has witnessed a rise in the number of low-energy and net-zero energy buil... more The U.S. housing market has witnessed a rise in the number of low-energy and net-zero energy buildings. Many of them integrate solar photovoltaic (PV) systems to reduce their electricity usage. In predicting the energy performance of a building design and the integrated PV system, builders utilize whole-building simulation programs. These programs either lack consideration of degradation, or are not explicit in the underlying assumptions of the model being used. In our analysis, we use the U.S. Department of Energy's Energy Plus (E+) Whole-building Energy Simulation program, along with alternative degradation model assumptions, to assess the impacts of system degradation on the energy and economic performance of the NIST Net-Zero Residential Test Facility (NZERTF). Alternative degradation rates and models are evaluated to understand the implications of alternative assumptions on system performance and economic viability. The performance sensitivity is compared to the sensitivity of the cost assumption parameters to determine the relative importance of solar PV degradation to the decision-making process.

Residential building energy efficiency is becoming increasingly important in U.S. energy policy. ... more Residential building energy efficiency is becoming increasingly important in U.S. energy policy. Analyzing the effectiveness of potential energy efficiency improvements in the residential sector involves running whole building energy simulations for alternative building designs. Such analysis requires detailed building design characteristics including climate, fuel type, energy technologies, and design improvements. For broad studies of the U.S. residential sector, prototypical designs representing "typical" residential buildings are necessary to provide the basis for this detailed analysis.

Building stakeholders need practical metrics, data, and tools to support decisions related to sus... more Building stakeholders need practical metrics, data, and tools to support decisions related to sustainable building designs, technologies, standards, and codes. The Engineering Laboratory of the National Institute of Standards and Technology (NIST) has addressed this high priority national need by extending its metrics and tools for sustainable building products, known as Building for Environmental and Economic Sustainability (BEES), to whole buildings. Whole building sustainability metrics have been developed based on innovative extensions to life-cycle assessment (LCA) and life-cycle costing (LCC) approaches involving whole building energy simulations. The measurement system evaluates the sustainability of both the materials and the energy used by a building over time. It assesses the "carbon footprint" of buildings as well as 11 other environmental performance metrics, and integrates economic performance metrics to yield science-based measures of the business case for investment choices in high-performance green buildings.

The National Institute of Standards and Technology (NIST) received funding through the American R... more The National Institute of Standards and Technology (NIST) received funding through the American Recovery and Reinvestment Act (ARRA) to construct a Net Zero Energy Residential Test Facility (NZERTF). The initial goal of the NZERTF is to demonstrate that a net-zero energy residential design can "look and feel" like a typical home in the Gaithersburg area. Demonstration phase of the project intends to demonstrate that the operation of the house does perform at "net zero," or produces as much electricity as it consumes over an entire year. The NZERTF is scheduled to begin the demonstration phase in 2013.

Energy efficiency requirements in energy codes for commercial buildings vary across states, and m... more Energy efficiency requirements in energy codes for commercial buildings vary across states, and many states have not yet adopted the latest energy efficiency standard edition. ). Some states do not have a code requirement for energy efficiency, leaving it up to the locality or jurisdiction to set its own requirements. This study considers the impacts that the adoption of newer, more stringent energy codes for commercial buildings would have on building energy use, operational energy costs, building life-cycle costs, and cradle-to-grave energy-related carbon emissions.

Energy efficiency requirements in energy codes for commercial buildings vary across states, and m... more Energy efficiency requirements in energy codes for commercial buildings vary across states, and many states have not yet adopted the latest energy efficiency standard edition. ). Some states do not have a code requirement for energy efficiency, leaving it up to the locality or jurisdiction to set its own requirements. This study considers the impacts that the adoption of newer, more stringent energy codes for commercial buildings would have on building energy use, operational energy costs, building life-cycle costs, and cradle-to-grave energy-related carbon emissions.