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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 19 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2022

Commercial Building Planning and Retrofitting Strategy for Grid Services

The increasing integration of distributed energy resources (DERs) plays an important role in improving energy consumption efficiency. In September 2020, the Federal Energy Regulatory Commission (FERC) approved Order 2222 which opens wholesale electricity markets to small capacity DERs. The benefit of this new FERC Order 2222 is that DERs, such as rooftop solar panels and batteries, will be able to participate in regional electricity markets and provide grid services. Meanwhile, the planning and operation strategies of DERs are facing new challenges to account for the impact of the wholesale market with numerous uncertainty factors. Therefore, in this paper, we propose a new planning and retrofitting model for long-term commercial buildings that considers both DER investment and market participation. Specifically, we explore the capability of implementing DERs for grid services. The effectiveness of the proposed model is validated using real-world data. Simulation results also validate that participating in grid services can significantly increase revenues through appropriate building energy management and shorten the payback period of DER investments.

building energy management↗
DOE OSTI2026

Are Deep Energy Retrofits in Commercial Buildings Including Window Upgrades?

U.S. Commercial buildings account for about 20% of total U.S. energy consumption. Because the thermal performance of windows significantly affects building energy efficiency and HVAC system performance, best practice guidance often includes window and envelope improvements in conjunction with HVAC upgrades to optimize energy use and improve occupant comfort. It is an open question, however, regarding how often these best practices are implemented in the field. This paper aims to address that gap by conducting a literature review and a series of interviews with commercial building auditing and management professionals to explore the factors that drive window retrofits in commercial buildings. The paper explores a range of case studies from deep energy retrofits across the globe, comparing projects with and without window retrofits. The primary goals of this review are to: (1) provide data from real-world case studies illustrating the role of windows in deep energy renovations and HVAC upgrades, (2) conduct retrofit cost analyses for windows and high-performance HVAC systems and (3) offer insights into how window upgrade decisions are made and when they are implemented as part of deep energy retrofits. Most of the retrofit studies focused exclusively on high performance HVAC upgrades without considering how window upgrades might further enhance the overall energy efficiency of commercial buildings. Interviews with building industry experts shed light on the key factors influencing deep energy retrofit decisions and what factors tip the scales in favor of including window measures with more comprehensive retrofit projects.

Cort, Katherine↗
DOE OSTI2021

The effect of building retrofit measures on CO2 emission reduction – A case study with U.S. Medium office buildings

Building retrofit has great potential to reduce CO2 emissions since buildings are responsible for 36% of emissions in the United States. Several existing studies have examined the effect of building retrofit measures on CO2 emission reduction. However, these studies oversimplified emission factors of electricity by adopting constant annual emission factors. This study uses hourly emission factors of electricity to analyze the effect of building retrofit measures on emission reduction using U.S. medium office buildings as an example. We analyzed CO2 emission reduction effects of eight building retrofit measures that related to envelop and mechanical system in five locations: Tampa, San Diego, Denver, Great Falls, and International Falls. The main findings are: (1) estimating CO2 emission reduction with constant emission factors overestimates the emission reduction for most measures in San Diego, while it underestimates the emission reduction for most measures in Denver and International Falls; (2) The same retrofit measure may have different effects in CO2 emission reduction depending on the climates. For instance, improving lighting efficiency and improving equipment efficiency have less impacts in emission reduction in cold climates than hot climates; and (3) The most energy efficient measure may not be the most emission efficient measure. For example, in Great Falls, the most energy efficient measure is improving equipment efficiency, but the most emission efficient measure is improving heating efficiency.

Lou, Yingli↗
DOE OSTI2024

Simulation & Analysis of the Hydronic Shell Retrofit System as a Solution for Deep Energy Retrofits and Electrification of Large Multifamily Housing Communities in Cold Climate

Among 32 million multi-family buildings in the United States, approximately 42% have poor or no insulation. Envelope retrofits of these buildings will provide thermal resiliency and enable a pathway to electrification of space heating systems as a result of improved thermal performance. Hydronic Shell (HS) is a technology which combines an insulated retrofit panel with a heating, ventilation and air-conditioning (HVAC) thus enabling both envelope retrofit and space heating electrification. In this study, we used whole building energy simulation to evaluate energy impact of multi-family building retrofit with hydronic shell system. The simulation was performed for four locations of New York, Syracuse, Chicago and Boston. The results from the simulation showed more than 66% cooling energy reduction and more than 88% heating energy reduction from Hydronic Shell retrofit compared to Baseline building in all four locations. This reduction in energy consumption resulted in up to 219 MT reduction in annual CO2 emission. The cost reduction per floor area achieved from HVAC energy consumption reduction using Hydronic Shell retrofit was 0.66 to 0.99 $\$$/ft 2 . The results also showed higher percentage of heating energy reduction comes from the envelope only retrofit and higher percentage of cooling energy reduction comes from the retrofit HVAC system for the four locations under study.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2018

Evaluation of NOx emissions of a retrofitted Euro 5 passenger car for the Horizon prize “Engine retrofit”

Highlights: • Many studies report diesel vehicles emitting more than 4 times the type approval NO{sub x} in real driving conditions. • One solution is retrofitting them, but there is no legislative background for passenger cars. • The Horizon 2020 prize for the “Engine Retrofit for Clean Air” aims at reducing the pollution in cities. • A Euro 5 retrofitted vehicle showed significant reductions over test cycles, but small at the cold start phases. • In some high speed conditions NH{sub 3} and N{sub 2}O were measured. The Horizon 2020 prize for the “Engine Retrofit for Clean Air” aims at reducing the pollution in cities by spurring the development of retrofit technology for diesel engines. A Euro 5 passenger car was retrofitted with an under-floor SCR (Selective Catalytic Reduction) for NO{sub x} catalyst in combination with a solid ammonia based dosing system as the NO{sub x} reductant. The vehicle was tested both on the road and on the chassis dynamometer under various test cycles and ambient temperatures. The NO{sub x} emissions were reduced by 350–1100 mg/km (60–85%) in the laboratory depending on the test cycle and engine conditions (cold or hot start), except at type approval conditions. The reduction for cold start urban cycles was < 75 mg/km (< 15%). The on road and laboratory tests were inline. In some high speed conditions significant increase of ammonia (NH{sub 3}) and nitrous oxide (N{sub 2}O) were measured. No effect was seen on other pollutants (hydrocarbons, carbon monoxide and particles). The results of the present study show that retrofitting high emitting vehicles can significantly reduce vehicle NO{sub x} emissions and ultimately pollution in cities.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2018

Energy Cost Savings of Systems-Based Building Retrofits: A Study of Three Integrated Lighting Systems in Comparison with Component Based Retrofits

Most building retrofit projects are still component-based in that they typically address only one piece or type of equipment at a time. Systems-based retrofits that seek to address multiple components in an integrated manner have the potential to provide significantly greater energy savings. Lawrence Berkeley National Laboratory (LBNL) partnered with several utilities to develop and evaluate three different integrated retrofit packages involving lighting systems: automated shading with daylight dimming controls, workstation-specific lighting with daylight controls, and task/ambient lighting with plug load occupancy controls. Specifically, our analysis sought to quantify the marginal benefits of these systems (energy savings as well as lighting performance and visual comfort) relative to component based approaches. The analysis was based on a combination of measured performance data from LBNL’s FLEXLAB® test facility and energy simulations. All three systems were compared to a simple fluorescent-to-LED retrofit, which represents the component-based approach. While the simple LED upgrade provides significant lighting energy savings of 63%, the systems yielded energy savings of 81-93%, which equates to additional savings of 49-82% over the simple LED upgrade. All systems tested provided satisfactory visual comfort as well, indicating good potential for market acceptance.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2016

Phased Retrofits in Existing Homes in Florida Phase II: Shallow Plus Retrofits

Originally published in February 2016, this revision contains an added section called 'Evaluation of Complete Central System Replacement with Inverter-Driven Heat Pump,' which presents the designs and energy savings evaluations of two different schemes wherein inverter-driven systems replaced a home's existing central system. Analyses for three additional retrofit measures were bolstered by longer-term data; these are described in the sections on supplemental mini-split heat pumps (MSHPs), smart thermostats, and heat pump clothes dryers. The sections on supplemental MSHPs and smart thermostats were also enhanced with larger sample sizes and projections of weather-normalized annual energy savings. Finally, peak system hour energy demand-reduction predictions are provided for all retrofit measures where meaningful impacts could be drawn.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2016

Phased Retrofits in Existing Homes in Florida Phase II: Shallow Plus Retrofits

Originally published in February 2016, this revision contains an added section called 'Evaluation of Complete Central System Replacement with Inverter-Driven Heat Pump,' which presents the designs and energy savings evaluations of two different schemes wherein inverter-driven systems replaced a home’s existing central system. Analyses for three additional retrofit measures were bolstered by longer-term data; these are described in the sections on supplemental mini-split heat pumps (MSHPs), smart thermostats, and heat pump clothes dryers. The sections on supplemental MSHPs and smart thermostats were also enhanced with larger sample sizes and projections of weather-normalized annual energy savings. Finally, peak system hour energy demand-reduction predictions are provided for all retrofit measures where meaningful impacts could be drawn.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2023

Getting Beyond Widgets: Performance of Efficient Indoor Air Quality System Retrofit Packages for Schools A report on the modeled energy, greenhouse gas, and cost savings of several multi-measure retrofit packages for energy efficiency and indoor air quality in primary schools

School facilities are often underfunded with aging and poorly maintained HVAC and lighting systems. Most existing school buildings stand to benefit significantly from retrofits in terms of energy, cost, and emissions savings. Ventilation and indoor air quality (IAQ), which are important aspects of a healthy and productive learning environment, can also be enhanced by some energy efficiency measures (EEMs). Packaging energy efficiency and IAQ systems retrofits may represent a golden opportunity to improve performance in this critical building sector.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2017

Building America Case Study: Pilot Demonstration of Phased Energy Efficiency Retrofits: Deep Retrofits, Central and South Florida

The Florida Solar Energy Center (FSEC), in collaboration with Florida Power & Light (FPL), is pursuing a phased residential energy-efficiency retrofit program in Florida. Researchers are looking to establish the impacts of technologies of two retrofit packages -- shallow and deep -- on annual energy and peak energy reductions.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2017

Building America Case Study: Pilot Demonstration of Phased Energy Efficiency Retrofits: Shallow Retrofit Results, Central and South Florida

The Florida Solar Energy Center (FSEC), in collaboration with Florida Power & Light (FPL), is pursuing a phased residential energy-efficiency retrofit program in Florida. Researchers are looking to establish the impacts of technologies of two retrofit packages -- shallow and deep -- on annual energy and peak energy reductions. Sixty homes have been instrumented to record total house power and detailed energy end-use data on all appliances as well as household interior temperature and relative humidity conditions.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2017

Building America Case Study: Pilot Demonstration of Phased Energy Efficiency Retrofits: Shallow Retrofit Results, Central and South Florida

The Florida Solar Energy Center (FSEC), in collaboration with Florida Power & Light (FPL), is pursuing a phased residential energy-efficiency retrofit program in Florida. Researchers are looking to establish the impacts of technologies of two retrofit packages -- shallow and deep -- on annual energy and peak energy reductions. Sixty homes have been instrumented to record total house power and detailed energy end-use data on all appliances as well as household interior temperature and relative humidity conditions.

BA-PIRC↗
DOE OSTI2024

Simulation & Analysis of the Hydronic Shell Retrofit System as a Solution for Deep Energy Retrofits and Electrification of Large Multifamily Housing Communities in Cold Climate

According to the 2020 residential energy consumption survey, there are 32 million multi-family buildings in the United States, and approximately 42% of these have poor or no insulation (US EIA 2020). Electrification of buildings with heat pump is one of the key strategies to achieve the goal of 90% reduction of greenhouse gas emissions in buildings by 2050 (U.S. Department of Energy 2024a). Building electrification will also enable greater penetration of variable renewable energy sources. However, replacing the natural gas dominated heating system by electrical appliance will increase the electrical load in heating dominated climate. It is crucial to well-insulate the building envelope to mitigate the stress in the grid from electrification. The hydronic shell (HS) system discussed next can achieve dual objective of envelope retrofit with space heating system electrification.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗