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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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Watch how NREL researchers are using the Smart Power Laboratory at the Energy Systems Integration Facility (ESIF) to develop technologies that will help the "smart homes" of the future perform efficiently and communicate effectively with the electricity grid while enhancing occupants' comfort and convenience.
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ET team research results are critical to achieving 50% energy savings across U.S. buildings within the next two decades. The ET team focuses on supporting research, development, and tech-to-market opportunities of high impact technologies, or those that demonstrate potential for achieving significant energy savings cost effectively.
In 2009, a 37-unit apartment complex located in Boulder, Colorado, underwent an energy retrofit to comply with Boulder SmartRegs Ordinance, a mandate that requires all rental properties to meet certain energy efficiency standards by 2018. The Consortium of Advanced Residential Buildings (CARB), a U.S. Department of Energy Building America team, worked with city planners and building owners to evaluate this program and recently completed a case study evaluating the effectiveness of a collection of retrofit measures.
Combustions safety is an important step in the process of upgrading homes for energy efficiency. There are several approaches used by field practitioners, but researchers have indicated that the test procedures in use are complex to implement and provide too many false positives. Field failures often mean that the house is not upgraded until after remediation or not at all, if not include in the program. In this report the PARR and NorthernSTAR DOE Building America Teams provide a simplified test procedure that is easier to implement and should produce fewer false positives.
"9Combustion safety is an important step in the process of upgrading homes for energy efficiency. There are several approaches used by field practitioners, but researchers have indicated that the test procedures in use are complex to implement and provide too many false positives. Field failures often mean that the house is not upgraded until after remediation or not at all, if not include in the program. In this report the PARR and NorthernSTAR DOE Building America Teams provide a simplified test procedure that is easier to implement and should produce fewer false positives. A survey of state weatherization agencies on combustion safety issues, details of a field data collection instrumentation package, summary of data collected over seven months, data analysis and results are included. The project provides several key results. State weatherization agencies do not generally track combustion safety failures, the data from those that do suggest that there is little actual evidence that combustion safety failures due to spillage from non-dryer exhaust are common and that only a very small number of homes are subject to the failures. The project team collected field data on 11 houses in 2015. Of these homes, two houses that demonstrated prolonged and excessive spillage were also the only two with venting systems out of compliance with the National Fuel Gas Code. The remaining homes experienced spillage that only occasionally extended beyond the first minute of operation. Combustion zone depressurization, outdoor temperature, and operation of individual fans all provide statistically significant predictors of spillage.
In this paper, we demonstrate the potential benefits that residential buildings can provide for frequency regulation services in the electric power grid. In a hardware-in-the- loop (HIL) implementation, simulated homes along with a physical laboratory home are coordinated via a grid aggregator, and it is shown that their aggregate response has the potential to follow the regulation signal on a timescale of seconds. Connected (communication-enabled), devices in the National Renewable Energy Laboratory's (NREL's) Energy Systems Integration Facility (ESIF) received demand response (DR) requests from a grid aggregator, and the devices responded accordingly to meet the signal while satisfying user comfort bounds and physical hardware limitations. Future research will address the issues of cybersecurity threats, participation rates, and reducing equipment wear-and-tear while providing grid services.
U.S. residential thermostats control approximately 9% of the nation’s energy use. Many building codes now require programmable thermostats (PTs) because of their assumed energy savings. However, several recent field studies have shown no significant savings or even higher energy use in households using PTs compared to those using non-PTs. These studies point to usability problems that lead to incorrect use and wasted energy. However, the lack of clear, consistent metrics has hampered the acceptance of usability concerns by thermostat manufacturers. Thus there is a need for metrics specific to PTs that manufacturers can use to evaluate their products. Here, we report on the results of a usability study conducted on five commercially available PTs and the development of four new metrics suitable for use in evaluating thermostat usability. Our study confirmed usability deficits in the current generation of PTs and showed the metrics are correlated with each other as well as agreeing with the qualitative results of the study.
Recent years have seen a dramatic increase in the number of “smart” devices available for residential buildings. This column describes opportunities presented by advances in smart home technology that could impact our homes and how we interact with them.
Miscellaneous electric loads (MELs) research dates back over thirty years, with the earliest publications on MELs originating in the late 1980s. As the number and types of MELs grew over the subsequent decades, so did the body of minimum energy performance standards (MEPS) and regulations put in place to control what is now an ever-growing source of energy consumption in the residential and commercial sectors. In particular, these MEPS are designed to control off-mode, standby, and connected standby power consumption to prevent energy waste. Research on MELs focuses a great deal on analyzing the characteristics of MELs, approaches for measuring their consumption, and at a higher level what constitutes a MEL. Despite these advances, there has yet to be a comparison of different approaches across regulatory bodies of MELs – both between and within countries – to identify similarities, gaps, and opportunities for crafting common language and testing procedures. This study provides an international analysis of MELs-related voluntary and mandatory MEPS across 12 economies to address this gap. The analysis demonstrates that even while economies may participate in shared commitments to regulated MELs energy consumption, there remains no common language for framing MELs, nor is there a shared understanding of updating aging test procedures used globally for verifying MELs-related MEPS.
The East Tennessee Technology Park (ETTP) is the site of five former gaseous diffusion plant (GDP) process buildings that were used to enrich uranium from 1945 to 1985. The process equipment in the original two buildings (K-25 and K-27) was used for the production of highly enriched uranium (HEU), while that in the three later buildings (K-29, K-31 and K-33) produced low enriched uranium (LEU). Equipment was contaminated primarily with uranium and to a lesser extent technetium (Tc). Decommissioning of the GDP process buildings has presented several unique challenges and produced many lessons-learned. Among these is the importance of good, up-front characterization in developing the best demolition approach. Also, chemical cleaning of process gas equipment and piping (PGE) prior to shutdown should be considered to minimize the amount of hold-up material that must be removed by demolition crews. Another lesson learned is to maintain shutdown buildings in a dry state to minimize structural degradation which can significantly complicate characterization, deactivation and demolition efforts. Perhaps the most important lesson learned is that decommissioning GDP process buildings is first and foremost a waste logistics challenge. Innovative solutions are required to effectively manage the sheer volume of waste generated from decontamination and demolition (D and D) of these enormous facilities. Finally, close coordination with Security is mandatory to effectively manage Special Nuclear Material (SNM) and classified equipment issues. (authors)
The Defense Waste Processing Facility processes legacy nuclear waste generated at the Savannah River Site during production of enriched uranium and plutonium required by the Cold War. The nuclear waste is first treated via a complex sequence of controlled chemical reactions and then vitrified into a borosilicate glass form and poured into stainless steel canisters. Converting the nuclear waste into borosilicate glass is a safe, effective way to reduce the volume of the waste and stabilize the radionuclides. One of the constituents in the nuclear waste is mercury, which is present because it served as a catalyst in the dissolution of uranium-aluminum alloy fuel rods. At high temperatures mercury is corrosive to off-gas equipment, this poses a major challenge to the overall vitrification process in separating mercury from the waste stream prior to feeding the high temperature melter. Mercury is currently removed during the chemical process via formic acid reduction followed by steam stripping, which allows elemental mercury to be evaporated with the water vapor generated during boiling. The vapors are then condensed and sent to a hold tank where mercury coalesces and is recovered in the tank's sump via gravity settling. Next, mercury is transferred from the tank sump to a purification cell where it is washed with water and nitric acid and removed from the facility. Throughout the chemical processing cell, compounds of mercury exist in the sludge, condensate, and off-gas; all of which present unique challenges. Mercury removal from sludge waste being fed to the DWPF melter is required to avoid exhausting it to the environment or any negative impacts to the Melter Off-Gas system. The mercury concentration must be reduced to a level of 0.8 wt% or less before being introduced to the melter. Even though this is being successfully accomplished, the material balances accounting for incoming and collected mercury are not equal. In addition, mercury has not been effectively purified and collected in the Mercury Purification Cell (MPC) since 2008. A significant cleaning campaign aims to bring the MPC back up to facility housekeeping standards. Two significant investigations are being undertaken to restore mercury collection. The SMECT mercury pump has been removed from the tank and will be functionally tested. Also, research is being conducted by the Savannah River National Laboratory to determine the effects of antifoam addition on the behavior of mercury. These path forward items will help us better understand what is occurring in the mercury collection system and ultimately lead to an improved DWPF production rate and mercury recovery rate. (authors)
Demolition of the K-25 Gaseous Diffusion Plant required establishing a non-credible risk of inadvertent criticality because a Criticality Accident Alarm System (CAAS) could not be reliably maintained operable as the building was being torn down. Preparation for, and demolition of, the facility was a multi-year long effort with significant changes in approach. The most significant change was to demolish the facility with as much of the process gas equipment and piping left in the facility as possible, rather than removing all process gas equipment and piping from the facility prior to demolishing the building structure only. The contractor had to adapt their approach to accommodate these changes. The normal approach to demolition was to remove all process gas equipment and piping prior to demolition, using Nuclear Criticality Safety (NCS) controls based on the double contingency principle, while CAAS coverage was intact. Then, the building structure was demolished with no requirement for a CAAS. This was the method used to demolish the K-33 Building, for example. In the case of K-25 demolition, all equipment and piping that met the Environmental Management Waste Management Facility (EMWMF) disposal cell Waste Acceptance Criteria (WAC) was left in the building and removed as part of the building demolition process. This resulted in significant quantities of fissionable material remaining in the building and being handled during demolition. The NCS Organization worked closely with several groups during preparation activities. A Data Management organization was established to specifically identify every piece of process gas equipment and piping in the facility so that it could be accounted for and characterized. Deactivation and Decommissioning (D and D) personnel conducted internal visual inspections, by remote camera, of all process gas equipment and piping larger than 3' diameter, to reveal any large deposits that would require removal. Non-Destructive Assay (NDA) of the vast majority of equipment and piping was required to quantify the amount of fissionable material remaining. Finally, all process gas equipment and piping larger than 3'' diameter was internally filled with foam, which was credited by NCS with immobilizing the remaining fissionable material such that large migration and accumulation could not occur during demolition activities. NCS personnel worked closely with all of these groups in order to acquire the data and information needed to establish a non-credible risk of inadvertent criticality during building demolition. Good communication and a close working relationship between NCS, the various D and D/characterization personnel, and the Department of Energy (DOE) ensured the success of the modified approach to building demolition. The same successful approach is currently underway in the K-27 Building as well. (authors)
For residential property owners preparing to rebuild homes in Maui, this fact sheet, produced by the National Renewable Energy Laboratory (NREL), a national laboratory of the U.S. Department of Energy (DOE), provides a brief introduction to the topics of renewable energy and energy efficiency for new residential construction, presents a few high-level considerations and key concepts, and provides a sampling of information on rebates, incentives, certification programs, standards, and relevant policies. This fact sheet is not intended to be comprehensive nor to replace local resources.