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At least 397 records · Page 22

Building Energy Analysis of Manufactured and Multifamily Housing Types in Juneau, Alaska

This report details the results of building energy modeling analysis evaluating the potential energy savings, economic outcomes, and grid-level electricity reduction associated with cold climate air source heat pump (ccASHP) adoption across multifamily and manufactured housing (MMFH) building typologies in the City and Borough of Juneau (CBJ). Three building archetypes were evaluated: multifamily 4-plex apartments, multifamily 8-plex apartments, and manufactured housing units. Building energy models were developed using OpenStudio-HPXML and calibrated to actual utility consumption data and local meteorological data from the Juneau International Airport weather station using an automated calibration tool following the BPI-2400-S-2015 v.2 standard for model calibration. Occupant behaviors present the greatest variability in successful calibrations. Calibrated models were benchmarked against a baseline electric resistance heating condition, with the selected ccASHP modeled as the retrofit condition and typical meteorological year weather data for all results generation.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

Leveraging Open-Source Tools for Collaborative Macro-energy System Modeling Efforts

The authors are founding team members of a new effort to develop an Open Energy Outlook for the United States. The effort aims to apply best practices of policy-focused energy system modeling, ensure transparency, build a networked community, and work toward a common purpose: examining possible US energy system futures to inform energy and climate policy efforts. Individual author biographies can be found on the project website: https://openenergyoutlook.org/.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

A Framework for Daylighting Optimization in Whole Buildings with OpenStudio

We present a toolkit and workflow for leveraging the OpenStudio (Guglielmetti et al. 2010) platform to perform daylighting analysis and optimization in a whole building energy modeling (BEM) context. We have re-implemented OpenStudio's integrated Radiance and EnergyPlus functionality as an OpenStudio Measure. The OpenStudio Radiance Measure works within the OpenStudio Application and Parametric Analysis Tool, as well as the OpenStudio Server large scale analysis framework, allowing a rigorous daylighting simulation to be performed on a single building model or potentially an entire population of programmatically generated models. The Radiance simulation results can automatically inform the broader building energy model, and provide dynamic daylight metrics as a basis for decision. Through introduction and example, this paper illustrates the utility of the OpenStudio building energy modeling platform to leverage existing simulation tools for integrated building energy performance simulation, daylighting analysis, and reportage.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Integrating physics-based models with sensor data: An inverse modeling approach

Physics-based building energy models (e.g., EnergyPlus) rely on some unknown input parameters (e.g., zone air infiltration) that are hard to measure, leading to uncertainty in simulation results especially for existing buildings with varying operating conditions. With the increasing deployment of smart thermostats, zone air temperature data are readily available, posing a new opportunity for building energy modeling if such data can be harnessed. This study presents a novel inverse modeling approach which inverses the zone air heat balance equation and uses the measured zone air temperature to analytically calculate the zone air infiltration rate and zone internal thermal mass (e.g., furniture, interior partitions), which are two important model parameters with great variability and difficult to measure. This paper introduces the technical concept and algorithms of the inverse models, their implementation in EnergyPlus, and verification using EnergyPlus simulated building performance data. The inverse modeling approach provides new opportunities for integrating data from massive IoT sensors and devices to enhance the accuracy of simulation results which are used to inform decision making on energy retrofits and efficiency improvements of existing buildings.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

An Extensible High Energy Density Modeling Tool for Extreme Regimes

The overreaching goal of the project is to develop a simulation capability to model an entire High Energy Density (HED) target heated by an X-ray Free Electron Laser (XFEL) beam including the surrounding material with a focus on target material associated with subsequent shots. Our primary objective is to study target fratricide problems, where radiation/debris from the current shot degrade the target for subsequent shots. This work will have a large impact on research being conducted at HED facilities where the quality of data is directly related to the effective repetition rate of the driver, which is often limited by target fratricide problems. This project focuses on a stream of closely spaced droplet targets that are appropriate for new very high repetition rate sources such as the ~1 MHz LCLS-II upgraded XFEL. The capability of the PISALE (Pacific Island Structured-AMR with ALE) code is extended to model this class of problems. We summarize the capability and improvements made to the HED branch of the PISALE code. We discuss our simulations of target fratricide for small (5 micron) hydrogen droplets heated by an XFEL beam at SLAC. We also compare simulations of the initial dynamics of larger (50 micron) water droplets, heated by the same XFEL beam, with experimental data. We briefly discuss training, dissemination, and related activities associated with this project.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗

International Energy Agency Ocean Energy Systems Task 10 Wave Energy Converter Modeling Verification and Validation: Preprint

This is the first joint reference paper for the Ocean Energy Systems (OES) Task 10 Wave Energy Converter modeling verification and validation group. The group is established under the OES Energy Technology Network program under the International Energy Agency. OES was founded in 2001 and Task 10 was proposed by Bob Thresher (National Renewable Energy Laboratory) in 2015 and approved by the OES Executive Committee EXCO in 2016. The kickoff workshop took place in September 2016, wherein the initial baseline task was defined. Experience from similar offshore wind validation/verification projects (OC3-OC5 conducted within the International Energy Agency Wind Task 30) [1], [2] showed that a simple test case would help the initial cooperation to present results in a comparable way. A heaving sphere was chosen as the first test case. The team of project participants simulated different numerical experiments, such as heave decay tests and regular and irregular wave cases. The simulation results are presented and discussed in this paper.

16 TIDAL AND WAVE POWER↗

Tuning the fluid wetting dynamics on gold microstructures using photoactive compounds

This work demonstrates how photoactive compounds can be used to tune the surface chemistry, surface free energy, and the wetting velocity of fluids on Spiropyran functionalized surfaces with different surface microstructures. Evidence of this photowetting effect is based on data showing: (1) the cyclic changes in the static, advancing, and receding contact angles $\theta$ CA for multiple UV$\rightleftarrows$vis photoswitching cycles with both smooth and microstructured surfaces and (2) the changes in the fluid wicking velocity (via UV$\rightleftarrows$vis photoswitching) on different Spiropyran functionalized hemiwicking surfaces. X-ray photoelectron spectroscopy is used to determine the efficiency of photoswitching caused by the quality of the Spiropyran functionalization. Reversible photoisomerization of Spiropyran generates a gradient in surface free energy, resulting in a similar change in contact angle ($\theta$ CA ) in the photoswitchable surfaces. In conclusion, by incorporating these changes into the Owens-Wendt and Van Oss surface energy models, the energy of smooth Au surfaces can also be predicted for both UV and visible light irradiations, where reversible contact angle variations of $\Delta$$\theta$ CA ≈ 5–10° are achieved with both water and water-ethanol mixtures due to the conversion of SP to merocyanine, which corresponds to a total free energy change of ~13% on the photoswitchable surface.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Component-Level Analysis of Heating and Cooling Loads in the U.S. Residential Building Stock

The residential building sector accounts for a substantial portion of total energy consumption in the United States and offers a significant opportunity for energy reduction and decarbonization through improvements in energy efficiency. Heating and air conditioning are the primary contributors to residential energy usage and electricity system peak demand. However, due to the diversity of the housing stock and the complexity of factors affecting heating and cooling demand, identifying the relative contributions to heating and cooling loads poses challenges. To address this, we applied the ResStock analysis tool to simulate 550,000 building energy models, providing statistical representation of residential buildings in the contiguous United States. We introduced outputs that quantified the heating and cooling influence of different components of a home, such as air leakage, envelope components (ceilings, walls, windows, foundations), internal heat gains from people, lighting, plug loads, and duct losses and gains. Leveraging the granularity of ResStock, we present a dataset to enable deeper understanding of the contributors to heating and cooling loads as a function of housing characteristics such as location, envelope efficiency, and building type. This work aims to support prioritization of research and development and informed decision-making for residential building decarbonization.

building simulation↗

Energy Savings Modeling and Inspection Guidelines for Commercial Building Federal Tax Deductions for Buildings in 2016 and Later

This document provides guidance for modeling and inspecting energy-efficient property in commercial buildings for certification of the energy and power cost savings related to Section 179D of the Internal Revenue Code (IRC) enacted in Section 1331 of the 2005 Energy Policy Act (EPAct) of 2005, noted in Internal Revenue Service (IRS) Notices 2006-52 (IRS 2006), 2008-40 (IRS 2008) and 2012-26 (IRS 2012), and updated by the Protecting Americans from Tax Hikes (PATH) Act of 2015. Specifically, Section 179D provides federal tax deductions for energy-efficient property related to a commercial building's envelope; interior lighting; heating, ventilating, and air conditioning (HVAC); and service hot water (SHW) systems. This document applies to buildings placed in service on or after January 1, 2016.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

Aniak Energy Action Plan

In 2017, the Native Village of Aniak received a grant for the Aniak Energy Efficiency Project from the United States Department of Energy Office of Indian Energy policy and programs. The objective of the project was to reduce and stabilize energy costs in tribal buildings by setting energy efficiency improvement goals to provide direction for a future retrofit project. This final report begins with information about the community of Aniak and the project procedure. Chapters follow on each component of the project. The project team began by recording information about the seven project buildings as well as the Aniak Traditional Council’s goals for each building. Tribal staff also gathered baseline data on each building, including their energy use and general condition. An energy professional surveyed each building, prepared an energy model using AkWarm-C energy modeling software to determine energy-saving retrofits, and completed energy audits, summarized within this report. Each energy audit lists energy efficiency measures and energy conservation measures to pursue to improve the building and decrease its energy use. This report also contains three resources to help with the next steps in an energy retrofit project: a data monitoring plan to track the building condition and energy use through a retrofit project, a maintenance plan to facilitate energy conservation, and a list of funding and training opportunities that could provide resources for a retrofit or training for maintenance staff. Finally, readers can find materials from the outreach component of the project which demonstrated sustainable practices to the community. This Energy Action Plan marks the conclusion of the Aniak Energy Efficiency Project, but is meant to lead to the next step towards safe, comfortable, and energy efficient tribal buildings that will continue to benefit the community of Aniak for many years to come.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

Kwigillingok Energy Action Plan

In 2017, the Native Village of Kwigillingok received a grant for the Kwigillingok Energy Efficiency Project from the United States Department of Energy Office of Indian Energy. The objective of the project was to reduce and stabilize energy costs in tribal buildings by setting energy efficiency improvement goals to provide direction for a future retrofit project. This final report begins with information about the community of Kwigillingok and the project procedure. Chapters follow on each component of the project. The project team began by recording information about the six project buildings as well as the I.R.A. Council’s goal for each building. Tribal staff also gathered baseline data on each building, including their energy use and general condition. An energy professional surveyed each building, prepared an energy model using AkWarm-C energy modeling software to determine energy-saving retrofits, and completed energy audits, summarized within this report. Each energy audit lists energy efficiency measures and energy conservation measures to pursue to improve the building and decrease its energy use. This report also contains three resources to help with the next steps in an energy retrofit project: a data monitoring plan to track the building condition and energy use through a retrofit project, a maintenance plan to facilitate energy conservation, and a list of funding and training opportunities that could provide resources for a retrofit or training for maintenance staff. Finally, readers can find materials from the outreach component of the project, which demonstrated sustainable practices to the community. This Energy Action Plan marks the conclusion of the Kwigillingok Energy Efficiency Project but is meant to lead to the next step towards safe, comfortable, and energy efficient tribal buildings that will continue to benefit the community of Kwigillingok for many years to come.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

Atmautluak Energy Action Plan

In 2017, the Native Village of Atmautluak received a grant for the Atmautluak Energy Efficiency Project from the United States Department of Energy Office of Indian Energy. The objective of the project was to reduce and stabilize energy costs in tribal buildings by setting energy efficiency improvement goals to provide direction for a future retrofit project. This final report begins with information about the community of Atmautluak and the project procedure. Chapters follow on each component of the project. The project team began by recording information about the six project buildings as well as the Traditional Council’s goal for each building. Tribal staff also gathered baseline data on each building, including their energy use and general condition. An energy professional surveyed each building, prepared an energy model using AkWarm-C energy modeling software to determine energy-saving retrofits, and completed energy audits, summarized within this report. Each energy audit lists energy efficiency measures and energy conservation measures to pursue to improve the building and decrease its energy use. This report also contains three resources to help with the next steps in an energy retrofit project: a data monitoring plan to track the building condition and energy use through a retrofit project, a maintenance plan to facilitate energy conservation, and a list of funding and training opportunities that could provide resources for a retrofit or training for maintenance staff. Finally, readers can find materials from the outreach component of the project which demonstrated sustainable practices to the community. This Energy Action Plan marks the conclusion of the Atmautluak Energy Efficiency Project, but is meant to lead to the next step towards safe, comfortable, and energy efficient tribal buildings that will continue to benefit the community of Atmautluak for many years to come.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

Akiachak Energy Action Plan

In 2017, the Akiachak Native Community received a grant for the Akiachak Energy Efficiency Project from the United States Department of Energy Office of Indian Energy. The objective of the project was to reduce and stabilize energy costs in tribal buildings by setting energy efficiency improvement goals to provide direction for a future retrofit project. This final report begins with information about the community of Akiachak and the project procedure. Chapters follow on each component of the project. The project team began by recording information about the nine project buildings as well as the I.R.A. Council’s goal for each building. Tribal staff also gathered baseline data on each building, including their energy use and general condition. An energy professional surveyed each building, prepared an energy model using AkWarm-C energy modeling software to determine energy-saving retrofits, and completed energy audits, summarized within this report. Each energy audit lists energy efficiency measures and energy conservation measures to pursue to improve the building and decrease its energy use. This report also contains three resources to help with the next steps in an energy retrofit project: a data monitoring plan to track the building condition and energy use through a retrofit project, a maintenance plan to facilitate energy conservation, and a list of funding and training opportunities that could provide resources for a retrofit or training for maintenance staff. Finally, readers can find materials from the outreach component of the project which demonstrated sustainable practices to the community. This Energy Action Plan marks the conclusion of the Akiachak Energy Efficiency Project, but is meant to lead to the next step towards safe, comfortable, and energy efficient tribal buildings that will continue to benefit the community of Akiachak for many years to come.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

The relative effect of noise at different times of day: An analysis of existing survey data

This report examines survey evidence on the relative impact of noise at different times of day and assesses the survey methodology which produces that evidence. Analyses of the regression of overall (24-hour) annoyance on noise levels in different time periods can provide direct estimates of the value of the parameters in human reaction models which are used in environmental noise indices such as LDN and CNEL. In this report these analyses are based on the original computer tapes containing the responses of 22,000 respondents from ten studies of response to noise in residential areas. The estimates derived from these analyses are found to be so inaccurate that they do not provide useful information for policy or scientific purposes. The possibility that the type of questionnaire item could be biasing the estimates of the time-of-day weightings is considered but not supported by the data. Two alternatives to the conventional noise reaction model (adjusted energy model) are considered but not supported by the data.

Fields, J. M.↗

Abrupt climate change and extinction events

There is a growing body of theoretical and empirical support for the concept of instabilities in the climate system, and indications that abrupt climate change may in some cases contribute to abrupt extinctions. Theoretical indications of instabilities can be found in a broad spectrum of climate models (energy balance models, a thermohaline model of deep-water circulation, atmospheric general circulation models, and coupled ocean-atmosphere models). Abrupt transitions can be of several types and affect the environment in different ways. There is increasing evidence for abrupt climate change in the geologic record and involves both interglacial-glacial scale transitions and the longer-term evolution of climate over the last 100 million years. Records from the Cenozoic clearly show that the long-term trend is characterized by numerous abrupt steps where the system appears to be rapidly moving to a new equilibrium state. The long-term trend probably is due to changes associated with plate tectonic processes, but the abrupt steps most likely reflect instabilities in the climate system as the slowly changing boundary conditions caused the climate to reach some threshold critical point. A more detailed analysis of abrupt steps comes from high-resolution studies of glacial-interglacial fluctuations in the Pleistocene. Comparison of climate transitions with the extinction record indicates that many climate and biotic transitions coincide. The Cretaceous-Tertiary extinction is not a candidate for an extinction event due to instabilities in the climate system. It is quite possible that more detailed comparisons and analysis will indicate some flaws in the climate instability-extinction hypothesis, but at present it appears to be a viable candidate as an alternate mechanism for causing abrupt environmental changes and extinctions.

Crowley, Thomas J.↗

Quasi-elastic nuclear scattering at high energies

The quasi-elastic scattering of two nuclei is considered in the high-energy optical model. Energy loss and momentum transfer spectra for projectile ions are evaluated in terms of an inelastic multiple-scattering series corresponding to multiple knockout of target nucleons. The leading-order correction to the coherent projectile approximation is evaluated. Calculations are compared with experiments.

Cucinotta, Francis A.↗

What a New Energy Efficiency Measure for Commercial Buildings Means to You

This article describes a new path for compliance with ASHRAE Standard 90.1-2016. The new approach will lead to increased flexibility for designers, multiple uses for the same building energy models, increased recognition of energy saving design strategies, and lower energy modeling costs.

Appendix G↗