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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 253 records · Page 14
All sourcesNASA NTRSDOE OSTI
DOE OSTI2013

Strategy Guideline: Energy Retrofits for Low-Rise Multifamily Buildings in Cold Climates

This Strategy Guideline explains the benefits of evaluating and identifying energy efficiency retrofit measures that could be made during renovation and maintenance of multifamily buildings. It focuses on low-rise multifamily structures (three or fewer stories) in a cold climate. These benefits lie primarily in reduced energy use, lower operating and maintenance costs, improved durability of the structure, and increased occupant comfort. This guideline focuses on retrofit measures for roof repair or replacement, exterior wall repair or gut rehab, and eating system maintenance. All buildings are assumed to have a flat ceiling and a trussed roof, wood- or steel-framed exterior walls, and one or more single or staged boilers. Estimated energy savings realized from the retrofits will vary, depending on the size and condition of the building, the extent of efficiency improvements, the efficiency of the heating equipment, the cost and type of fuel, and the climate location.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2013

Field Assessment of Energy Audit Tools for Retrofit Programs

This project focused on the use of home energy ratings as a tool to promote energy retrofits in existing homes. A home energy rating provides a quantitative appraisal of a home’s energy performance, usually compared to a benchmark such as the average energy use of similar homes in the same region. Rating systems based on energy performance models, the focus of this report, can establish a home’s achievable energy efficiency potential and provide a quantitative assessment of energy savings after retrofits are completed, although their accuracy needs to be verified by actual measurement or billing data. Ratings can also show homeowners where they stand compared to their neighbors, thus creating social pressure to conform to or surpass others. This project field-tested three different building performance models of varying complexity, in order to assess their value as rating systems in the context of a residential retrofit program: Home Energy Score, SIMPLE, and REM/Rate.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2014

Evaluation of Crawlspace Retrofits in Multifamily Buildings

In 2011 and early 2012, Building Science Corporation (BSC) collaborated with Innova Services Corporation on a multifamily community unvented crawlspace retrofit project at Oakwood Gardens in Lansdale, Pennsylvania. BSC provided design consulting services and pre- and post-retrofit evaluation, testing, and data monitoring. The existing condition was a vented crawlspace with an uninsulated floor between the crawlspace and the dwelling units above. The crawlspace was therefore a critically weak link in the building enclosure and was ripe for improvement. Saving energy was the primary interest and goal, but the greatest challenge in this unvented crawlspace retrofit project was working through a crawlspace bulk water intrusion problem caused by inadequate site drainage, window well drainage, foundation wall drainage, and a rising water table during rainy periods.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2015

Evaluation of an LED Retrofit Project at Princeton University’s Carl Icahn Laboratory

The LED lighting retrofit at the Carl Icahn Laboratory of the Lewis-Sigler Institute for Integrative Genomics was the first building-wide interior LED project at Princeton University, following the University’s experiences from several years of exterior and small-scale interior LED implementation projects. The project addressed three luminaire types – recessed 2x2 troffers, cove and other luminaires using linear T8 fluorescent lamps, and CFL downlights - which combined accounted for over 564,000 kWh of annual energy, over 90% of the lighting energy used in the facility. The Princeton Facilities Engineering staff used a thorough process of evaluating product alternatives before selecting an acceptable LED retrofit solution for each luminaire type. Overall, 815 2x2 luminaires, 550 linear fluorescent luminaires, and 240 downlights were converted to LED as part of this project. Based solely on the reductions in wattage in converting from the incumbent fluorescent lamps to LED retrofit kits, the annual energy savings from the project was over 190,000 kWh, a savings of 37%. An additional 125,000 kWh of energy savings is expected from the implementation of occupancy and task-tuning control solutions, which will bring the total savings for the project to 62%.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2019

Wall Upgrades for Residential Deep Energy Retrofits: A Literature Review

In the United States, 39% of total energy consumption comes from the building sector, 20% of which is attributed to residential buildings. New, high-performance homes incorporate a combination of tight building envelopes, mechanical ventilation and efficient components to ensure comfort, adequate airflow and moisture control. These systems work together to create energy efficient homes that employ measures to manage moisture and indoor pollutants. Older homes, built before 1992 when DOE’s Building Energy Codes Program was established represent approximately 68% of building stock in the country, and often have significant air leakage and inadequate insulation. Homes with little to no air sealing or insulation result in heating and cooling losses, which can represent a substantial portion of utility bills. Done correctly, deep energy retrofits (DERs) can significantly improve the energy performance of a home’s thermal envelope, decrease indoor pollutants and increase homeowner comfort. This literature review summarizes current practices for exterior wall retrofits for existing homes, provides an overview of techno-economic approaches to investigate residential wall systems, and discusses thermal and hygrothermal modeling strategies. Accompanying this literature review is a larger effort to identify state-of-the-art technologies for existing wall energy efficiency retrofit systems that can be applied over existing siding and are suitable for the cold/very cold climates.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2021

U.S.-China Clean Energy Research Center Building Energy Efficiency (CERC-BEE) Open-Source Retrofit Targeting Tool (CRADA FP00007338 Final Report)

To increase the cost-saving energy and carbon dioxide (CO 2 ) emissions reductions in buildings and portfolios at the scale and speed necessary to limit climate change, researchers at LBNL and Johnson Controls (JCI) developed the Building Efficiency Targeting Tool for Energy Retrofits (BETTER). BETTER is a software tool that consists of three components: (1) the BETTER analytical engine source code (which was developed with intellectual property provided by JCI under CRADA FP00007338); (2) the BETTER web application, developed by LBNL and McQuillen Interactive Pty. Ltd; and (3) the BETTER application programming interface (API), also developed by LBNL and McQuillen Interactive Pty. Ltd. BETTER enables building and portfolio owners, managers, and service providers worldwide to quickly, easily identify cost-saving energy efficiency retrofits in existing buildings and portfolios without expensive site visits or complex modeling. With minimal data input, the tool benchmarks a building’s electric and fossil energy usage against peers; quantifies energy, cost and greenhouse gas (GHG) emission reduction potentials at the building and portfolio levels; and recommends energy efficiency measures to decarbonize and electrify buildings and portfolios, targeting specific energy savings levels. No other tool so comprehensively analyzes buildings and portfolios with such ease. If fully implemented, it is estimated that BETTER could help reduce emissions equivalent to planting 1.3 billion trees globally by 2030. Moreover, an additional 50-75% of embodied GHG emissions could be avoided in each case where BETTER results in a building being retrofitted instead of demolished and replaced, providing substantial additional decarbonization benefits for the buildings sector. BETTER has garnered multiple awards and avid interest from investors. In 2020, it earned a R&D 100 Award for innovation and a LBNL Director’s Award for Technology Transfer. In 2021, BETTER was named an EarthX E-Capital Summit Climate Tech Prize semi-finalist

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2024

Evaluation of flame propagation of retrofit energy efficient wall assemblies

Leveraging safety science experience and industry relationships, UL Solutions and the International Association of Fire Fighters (IAFF) initiated a joint project in 2022 under an agreement with the US Department of Energy to evaluate the flame propagation of retrofit energy efficient wall assemblies. A draft of the protocol from the ASTM work was used to test and comparatively study various retrofit energy efficient designs to gain a better understanding of their fire behavior. The goals of this study were as follows: Develop an understanding of fire propagation across new, cost effective, and energy efficient exterior retrofit wall assemblies. Refine the flame propagation draft test method for exterior wall assemblies based on ASTM E2707. Identify conditions that create fire propagation hazards in exterior wall assemblies and educate the fire service on the findings.

42 ENGINEERING↗
DOE OSTI2025

Project-specific considerations for retrofitting carbon capture technology to power generating and industrial facilities

The National Energy Technology Laboratory (NETL) has previously reported on learnings from 7 FEED studies examining retrofitting power plants with capture. This presentation builds on this effort by highlighting learnings from 3 additional FEED studies examining retrofitting power plants with capture and 7 FEED and pre-FEED studies examining retrofitting industrial plants with capture. This includes a discussion of the design, performance, and cost implications associated with (1) site-specific considerations such as water availability, land availability, and site accessibility, and (2) host-plant-specific factors such as flue gas specifications, operational mode, and allowable degree of integration between the capture system and host plant.

FEED Studies↗
DOE OSTI2025

Dynamic Analysis of a Six-Cable Parallel Robot for Automated Panelized Building Retrofits

Cable-Driven Parallel Robots (CDPRs) are highly suitable for automated panelized building retrofits, thanks to their compact footprint and high payload-to-weight ratio. A common CDPR configuration featuring eight cables, where the anchors form a rectangular prism in front of the building facade, offers a large wrench feasible workspace and good control versatility. However, installing upper anchor points requires additional support structures, such as towers or beams, increasing setup complexity and posing logistical challenges in construction settings. To mitigate these challenges, we propose a six-cable CDPR model specifically designed for automated panelized building retrofits. Although the feasible workspace is limited, our analysis shows that the proposed CDPR adequately covers the critical areas required for panel installation. To validate that the six-cable system can effectively transport the end effector to the desired installation pose, we calculated optimal trajectories based on a constrained dynamic model. The simulation results of the six-cable CDPR demonstrate promising potential for automated panelized building retrofits, effectively balancing simplicity, cost-effectiveness, and functionality.

Liu, Yifang [ORNL] (ORCID:0000000190817417)↗
NASA NTRS1979

Space shuttle orbiter trimmed center-of-gravity extension study. Volume 3: Impact of retrofits for center-of-gravity extension on orbiter thermal-protection system

Heat transfer studies were conducted at Mach 10.3 on space shuttle orbiter models with the S-2 fillet and C-4 canard retrofit moldlines which were generated in aerodynamic and system design studies to increase the allowable c.g. range of the orbiter. Areas of orbiter most strongly affected were the sides where a shear layer which separated along the wing leading edge impinged. Analytical studies of the heating effect on the thermal-protection system were made which indicated that scar weight on the orbiter sides due to allowances for retrofits of the S-2 fillet and C-4 canard is small (less than about 90 kg (200 lbs) in comparison to the total weight of the retrofit).

Dunavant, J. C.↗
NASA NTRS1990

Considerations for the retrofit of data link

Human factors issues related to the retrofit of data link in commercial transport aircraft are discussed. Topics that must be considered for data link implementation include, the loss of the party line, (i.e., the availability to all aircraft of information transmitted on a common voice frequency), and the scheduling of information to the flight crew. This paper focuses primarily on the human factors issues related to retrofit of Mode S. Retrofits is a difficult task because panel space accessible to flight crew members is limited. As with all cockpit equipment, data link implementation will have to comply with Federal Aviation Regulation 25.1523, which requires the manufacturer to address the conspicuity and ease of use of the data link device, and to assess the impact on crew workload. Operational sequence diagrams are provided to illustrate a methodology that can be used to decompose the flight crew body channel utilization of candidate avionics configurations in order to optimize the pilot-vehicle interface.

Corwin, William H.↗
NASA NTRS1998

Infrastructure Retrofit Design via Composite Mechanics

Select applications are described to illustrate the concept for retrofitting reinforced concrete infrastructure with fiber reinforced plastic laminates. The concept is first illustrated by using an axially loaded reinforced concrete column. A reinforced concrete arch and a dome are then used to illustrate the versatility of the concept. Advanced methods such as finite element structural analysis and progressive structural fracture are then used to evaluate the retrofitting laminate adequacy. Results obtains show that retrofits can be designed to double and even triple the as-designed load of the select reinforced concrete infrastructures.

Chamis, Christos, C.↗
DOE OSTI2013

High-Efficiency Retrofit Lessons for Retail from a SuperTarget: Preprint

The National Renewable Energy Laboratory partnered with Target under the Commercial Building Program to design and implement a retrofit of a SuperTarget in Thornton, CO. The result was a retrofit design that predicted 37% energy savings over ASHRAE Standard 90.1-2004, and 29% compared to existing (pre-retrofit) store consumption. The largest savings came from energy efficient lighting, energy efficient cooling systems, improved refrigeration, and better control of plug loads.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2012

Energy and Cost Savings of Retro-Commissioning and Retrofit Measures for Large Office Buildings

This paper evaluates the energy and cost savings of seven retro-commissioning measures and 29 retrofit measures applicable to most large office buildings. The baseline model is for a hypothetical building with characteristics of large office buildings constructed before 1980. Each retro-commissioning measure is evaluated against the original baseline in terms of its potential of energy and cost savings while each retrofit measure is evaluated against the commissioned building. All measures are evaluated in five locations (Miami, Las Vegas, Seattle, Chicago and Duluth) to understand the impact of weather conditions on energy and cost savings. The results show that implementation of the seven operation and maintenance measures as part of a retro-commissioning process can yield an average of about 22% of energy use reduction and 14% of energy cost reduction. Widening zone temperature deadband, lowering VAV terminal minimum air flow set points and lighting upgrades are effective retrofit measures to be considered.

Wang, Weimin↗
DOE OSTI2013

Roof and Attic Design Guidelines for new and retrofit Construction of Homes in Hot and Coild Climates

Some guidelines for improving the energy efficiency of roofs and attics are presented and are based on the research of the DOE Building Technology. The results of combined analytical and experimental studies were used to benchmark computer tools, which in turn, were used to simulate homes in hot and cold climates. Adding floor and roof insulation, above deck ventilation, radiant barriers, cool color shingle, metal or tile roofs, sealing the attic floor, sealing the duct system and sealing the attic were simulated to compute the cost of energy savings. Results are prioritized to help building owners make an informed economic decision when contemplating roof and attic retrofits. Sealing the attic floor is a top retrofit option. The sealed attic approach and a new prototype roof assembly an insulated and ventilated roof are good options for retrofit work but have paybacks ranging from 15 to 25 years. A new sealed attic concept was simulated and computations show its simple payback is about 10 to 12 years in hot and cold climates; its first cost is significantly reduced from that of a spray foam approach. For new construction the best option is to keep the ducts out of the attic, make sure the attic floor is sealed and add at least code level of insulation to the ceiling.

attic↗
DOE OSTI2015

Cold Climate and Retrofit Applications for Air-to-Air Heat Pumps

Air source heat pumps (ASHP) including air-to-air ASHPs are easily applied to buildings almost anywhere for new construction as well as retrofits or renovations. They are widespread in milder climate regions but their use in cold regions is hampered due to low heating efficiency and capacity at cold outdoor temperatures. Retrofitting air-to-air ASHPs to existing buildings is relatively easy if the building already has an air distribution system. For buildings without such systems alternative approaches are necessary. Examples are ductless, minisplit heat pumps or central heat pumps coupled to small diameter, high velocity (SDHV) air distribution systems. This article presents two subjects: 1) a summary of R&D investigations aimed at improving the cold weather performance of ASHPs, and 2) a brief discussion of building retrofit options using air-to-air ASHP systems.

Baxter, Van D↗
DOE OSTI2018

LCA of Carbon Capture Retrofit Using the “Petra Nova Style” Model - LCAXVIII

This work was presented at the American Center for Life Cycle Assessment (ACLCA) LCAXVIII Conference in Fort Collins, CO on September 26, 2018. This analysis compares the life cycle environmental impacts for an amine-based capture retrofit with an external co-gen source providing the utility inputs for capture compared to a more traditional retrofit in which the plant/unit output is de-rated with the utility inputs for operating the capture system coming directly from the plant. One of the major differences between the designs is that in the case of the external co-gen unit, the combustion emissions associated with operating the capture unit are not part of the flue gas stream that is directed to the capture unit. Another unique consideration in this analysis is the inclusion of the upstream natural gas life cycle in the boundaries of the co-gen retrofit.

Krynock, Michelle↗
DOE OSTI2020

Retrofit-ability: A supplementary metric to inform energy efficiency policies and programs

Building Energy Use Intensity (EUI) has been commonly used to facilitate policy makers and utilities to design energy efficacy programs and help building managers prioritize investment in building upgrades. Buildings with higher EUIs are usually chosen as better candidates for retrofit. Our study of nearly one hundred buildings in Seattle’s Building Tune Up Accelerator program and thousands of buildings in the Asset Score database reveals that EUI (after weather/location/use type normalization) alone is not the best indicator of a building’s potential to save energy, especially for those buildings in the mid-range (30-70 percentile EUI). In this paper, we introduce the concept of “retrofit-ability” — a building’s real potential to reduce its energy use cost-effectively — as a supplementary metric to inform energy efficiency policy and investment. Currently, such potential analyses are predicted for a building stock using prototypical building models or statistical data. However, typical buildings or general historical data may not sufficiently represent building configurations in a portfolio and predict their saving potentials. We utilized machine learning to investigate how key building characteristics (such as envelope attributes, HVAC type, location, use type, etc.) affect a building’s improvement potentials and developed a low-cost method to quantify such potentials for a portfolio of buildings. The supplementary perspective provided by “retrofit-ability” highlights which building assets correlate most with a building’s energy savings potential across region, building use type and more.

Wang, Na↗