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Low Carbon Development Pathways for Cooling: Leveraging Kigali Amendment Across Residential Applications
Heating and cooling demand for space conditioning and refrigeration accounts for around a fifth of global final energy consumption. Climate change, urbanisation, and economic development have tripled electricity demand for cooling alone since the 1990s, with the majority coming from the use of inefficient cooling equipment, which burdens electricity grids, especially during the peak hours. It is imperative to address the energy required to provide cooling. The Kigali Amendment to the Montreal Protocol addresses these needs by setting ambitious global targets to phase down refrigerants with high global warming potential, while improving energy efficiency. Integrating energy efficiency and the refrigerant transition will contribute to economic security, well-being, energy access and security, and sustainability among the G20 countries.
Energy Savings - NETL Earth Day
NETL provides definitions and examples of energy efficiency and energy conservation.
Redox regulation of energy transfer efficiency in antennas of green photosynthetic bacteria
The efficiency of energy transfer from the peripheral chlorosome antenna structure to the membrane-bound antenna in green sulfur bacteria depends strongly on the redox potential of the medium. The fluorescence spectra and lifetimes indicate that efficient quenching pathways are induced in the chlorosome at high redox potential. The midpoint redox potential for the induction of this effect in isolated chlorosomes from Chlorobium vibrioforme is -146 mV at pH 7 (vs the normal hydrogen electrode), and the observed midpoint potential (n = 1) decreases by 60 mV per pH unit over the pH range 7-10. Extraction of isolated chlorosomes with hexane has little effect on the redox-induced quenching, indicating that the component(s) responsible for this effect are bound and not readily extractable. We have purified and partially characterized the trimeric water-soluble bacteriochlorophyll a-containing protein from the thermophilic green sulfur bacterium Chlorobium tepidum. This protein is located between the chlorosome and the membrane. Fluorescence spectra of the purified protein indicate that it also contains groups that quench excitations at high redox potential. The results indicate that the energy transfer pathway in green sulfur bacteria is regulated by redox potential. This regulation appears to operate in at least two distinct places in the energy transfer pathway, the oligomeric pigments in the interior of the chlorosome and in the bacteriochlorophyll a protein. The regulatory effect may serve to protect the cell against superoxide-induced damage when oxygen is present. By quenching excitations before they reach the reaction center, reduction and subsequent autooxidation of the low potential electron acceptors found in these organisms is avoided.
Alaska's Rural Building Stock: a Validation Study Using ResStock and Field Data
The availability of accurate national data on demographics, building stock, and energy use is vital for modeling residential buildings and evaluating decarbonization strategies. However, rural and Indigenous populations, including those in rural Alaska, are typically underrepresented in these datasets. These communities face unique challenges due to their remote locations, severe weather conditions, and limited access to resources, resulting in high energy burden. This report examines how rural Alaskan communities are underrepresented in the ResStock housing model and highlights the need for improved data to address their unique housing and energy challenges. Thus, this report examines the representation of rural Alaskan communities within the national housing stock model, ResStock. A validation study was conducted, considering ResStock, Field Data and Aerial and 3D-view data collection (A3DDC) datasets. The validation process started by using the down selecting approach on the ResStock building stock dataset. For the purpose of this study, only the rural Alaska Boroughs and Census areas located in ASHRAE IECC Climate Zone 8 were considered to ensure a more accurate and fair comparison with the field data, which was collected in rural areas located in climate zone 8, specifically within the Nome Census area. While ResStock may accurately represent several characteristics of the building stock for rural Alaska, some differences between modeled, field data, and aerial and 3D-view data collection datasets were identified. The following building characteristics have a high impact on modeled energy consumption and demonstrated large differences: Revisit heating setpoints and consider a substantially higher setpoint distribution, it could potentially address "missing loads" if this is the case. Develop and include Toyo heating in future modeling for ResStock and EnergyPlus. Remove natural gas as a water heater fuel type outside of North Slope County. Foundation type updated to have more crawlspaces rather than basements. Infiltration rates need reexamination for a larger distribution toward higher infiltration rates. Include more vinyl and less brick in exterior wall type and revise wall color for greater proportion of light rather than dark color. Roof material revised from majority shingles to majority metal. Update number of occupants to higher number of occupant count. Building orientation represents a higher proportion of south facing buildings rather than relatively equal. The findings suggest that updating ResStock's probability logic could better represent rural Alaskan buildings. ResStock can be utilized to identify the best upgrades or energy efficiency and energy efficiency improvements, helping community leaders in making more informed decisions.
Spectrum splitting using multi-layer dielectric meta-surfaces for efficient solar energy harvesting
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Characterization of cellulosic wastes and gasification products from chicken farms
Highlights: Black-Right-Pointing-Pointer The gas chromatography indicated the variable quality of the producer gas. Black-Right-Pointing-Pointer The char had appreciable NPK values, and can be used as a fertiliser. Black-Right-Pointing-Pointer The bio-oil produced was of poor quality, having high moisture content and low pH. Black-Right-Pointing-Pointer Mass and energy balances showed inadequate level energy recovery from the process. Black-Right-Pointing-Pointer Future work includes changing the operating parameters of the gasification unit. - Abstract: The current article focuses on gasification as a primary disposal solution for cellulosic wastes derived from chicken farms, and the possibility to recover energy from this process. Wood shavings and chicken litter were characterized with a view to establishing their thermal parameters, compositional natures and calorific values. The main products obtained from the gasification of chicken litter, namely, producer gas, bio-oil and char, were also analysed in order to establish their potential as energy sources. The experimental protocol included bomb calorimetry, pyrolysis combustion flow calorimetry (PCFC), thermo-gravimetric analyses (TGA), differential scanning calorimetry (DSC), Fourier transform infrared (FT-IR) spectroscopy, Raman spectroscopy, elemental analyses, X-ray diffraction (XRD), mineral content analyses and gas chromatography. The mass and energy balances of the gasification unit were also estimated. The results obtained confirmed that gasification is a viable method of chicken litter disposal. In addition to this, it is also possible to recover some energy from the process. However, energy content in the gas-phase was relatively low. This might be due to the low energy efficiency (19.6%) of the gasification unit, which could be improved by changing the operation parameters.
Supporting a Clean Energy Economy 2013-2018
The National Governor’s Association Center for Best Practices energy staff is focused on developing and implementing innovative solutions to state energy policy challenges. Among NGA’s energy teams focus are topics such as energy affordability, resilience, and reliability, which align with priorities of DOE’s WIP office. Given NGA’s direct connections with governors’ offices and longstanding support to governors’ policy staff on energy efficiency, renewable energy, resilience, reliability, affordability, and related topics, we are well suited to work alongside the U.S. Department of Energy (DOE) to support governors’ offices and key energy staff, address longstanding challenges, and deliver best practice solutions.
Advanced Aerodynamics. Selected NASA Research
This Conference Publication contains selected NASA papers that were presented at the Fifth Annual Status Review of the NASA Aircraft Energy Efficiency (ACEE) Energy Efficient Transport (EET) Program held at Dryden Flight Research Center in Edwards, California on September 14 to 15, 1981. These papers describe the status of several NASA in-house research activities in the areas of advanced turboprops, natural laminar flow, oscillating control surfaces, high-Reynolds-number airfoil tests, high-lift technology, and theoretical design techniques.
Electrochemical Hydrogen Peroxide Generator
Two-electron reduction of oxygen to produce hydrogen peroxide is a much researched topic. Most of the work has been done in the production of hydrogen peroxide in basic media, in order to address the needs of the pulp and paper industry. However, peroxides under alkaline conditions show poor stabilities and are not useful in disinfection applications. There is a need to design electrocatalysts that are stable and provide good current and energy efficiencies to produce hydrogen peroxide under acidic conditions. The innovation focuses on the in situ generation of hydrogen peroxide using an electrochemical cell having a gas diffusion electrode as the cathode (electrode connected to the negative pole of the power supply) and a platinized titanium anode. The cathode and anode compartments are separated by a readily available cation-exchange membrane (Nafion 117). The anode compartment is fed with deionized water. Generation of oxygen is the anode reaction. Protons from the anode compartment are transferred across the cation-exchange membrane to the cathode compartment by electrostatic attraction towards the negatively charged electrode. The cathode compartment is fed with oxygen. Here, hydrogen peroxide is generated by the reduction of oxygen. Water may also be generated in the cathode. A small amount of water is also transported across the membrane along with hydrated protons transported across the membrane. Generally, each proton is hydrated with 3-5 molecules. The process is unique because hydrogen peroxide is formed as a high-purity aqueous solution. Since there are no hazardous chemicals or liquids used in the process, the disinfection product can be applied directly to water, before entering a water filtration unit to disinfect the incoming water and to prevent the build up of heterotrophic bacteria, for example, in carbon based filters. The competitive advantages of this process are: 1. No consumable chemicals are needed in the process. The only raw materials needed are water and oxygen or air. 2. The product is pure and can therefore be used in disinfection applications directly or after proper dilution with water. 3. Oxygen generated in the anode compartment is used in the electrochemical reduction process; in addition, external oxygen is used to establish a high flow rate in the cathode compartment to remove the desired product efficiently. Exiting oxygen can be recycled after separation of liquid hydrogen peroxide product, if so desired. 4. The process can be designed for peroxide generation under microgravity conditions. 5. High concentrations of the order of 6-7 wt% can be generated by this method. This method at the time of this reporting is superior to what other researchers have reported. 6. The cell design allows for stacking of cells to increase the hydrogen peroxide production. 7. The catalyst mix containing a diquaternary ammonium compound enabled not only higher concentration of hydrogen peroxide but also higher current efficiency, improved energy efficiency, and catalyst stability. 8. The activity of the catalyst is maintained even after repeated periods of system shutdown. 9. The catalyst system can be extended for fuel-cell cathodes with suitable modifications.
Targeting Net Zero Energy at Marine Corps Base Hawaii, Kaneohe Bay: Preprint
This paper summarizes the results of an NREL assessment of Marine Corps Base Hawaii (MCBH), Kaneohe Bay to appraise the potential of achieving net zero energy status through energy efficiency, renewable energy, and hydrogen vehicle integration.
State and Local Planning for Energy (SLOPE) Platform
This fact sheet outlines the basic overview features, purpose, and additional information for the State and Local Planning for Energy (SLOPE) Platform. SLOPE is a collaboration between nine U.S. Department of Energy (DOE) technology offices and the National Renewable Energy Laboratory (NREL), integrates and delivers jurisdictionally resolved potential and projection data on energy efficiency, renewable energy, and sustainable transportation in an easy-to-access online platform to enable data-driven state and local energy planning and decision-making.
Opportunities and Challenges for Water and Wastewater Industries to Provide Exchangeable Services
Water and wastewater treatment plants and distribution systems use significant amounts of energy, around 2 - 4% of the total electricity used in the US, and their energy use is projected to increase as populations increase and regulations become more stringent. Water and wastewater systems have largely been disconnected from the electric utilities' efforts to improve energy efficiency and provide energy efficiency and provide grid services, likely because their core mission is to provide clean water and treated wastewater. Energy efficiency has slowly crept into the water and wastewater industry as the economic benefit has become more apparent, but there is still potential for significant improvement. Some of the larger, more progressive water utilities are starting to consider providing grid services; however, it remains a foreign concept to many. This report explores intrinsic mechanisms by which the water and wastewater industries can provide exchangeable services, the benefit to the parties involved, and the barriers to implementation. It also highlights relevant case studies and next steps. Although opportunities for increasing process efficiencies are certainly available, this report focuses on the exchangeable services that water and wastewater loads can provide to help maintain grid reliability, keep overall costs down, and increase the penetration of distributed renewables on the electric grid. These services have potential to provide water utilities additional value streams, using existing equipment with modest or negligible upgrade cost.
Analysis of energy recovery potential using innovative technologies of waste gasification
Highlights: Black-Right-Pointing-Pointer Energy recovery from waste by gasification was simulated. Black-Right-Pointing-Pointer Two processes: high temperature gasification and gasification associated to plasma. Black-Right-Pointing-Pointer Two types of feeding waste: Refuse Derived Fuel (RDF) and pulper residues. Black-Right-Pointing-Pointer Different configurations for the energy cycles were considered. Black-Right-Pointing-Pointer Comparison with performances from conventional Waste-to-Energy process. - Abstract: In this paper, two alternative thermo-chemical processes for waste treatment were analysed: high temperature gasification and gasification associated to plasma process. The two processes were analysed from the thermodynamic point of view, trying to reconstruct two simplified models, using appropriate simulation tools and some support data from existing/planned plants, able to predict the energy recovery performances by process application. In order to carry out a comparative analysis, the same waste stream input was considered as input to the two models and the generated results were compared. The performances were compared with those that can be obtained from conventional combustion with energy recovery process by means of steam turbine cycle. Results are reported in terms of energy recovery performance indicators as overall energy efficiency, specific energy production per unit of mass of entering waste, primary energy source savings, specific carbon dioxide production.
2010 Northwest Federal Market Assessment Report
The primary intent of this market assessment is to provide insights on the effectiveness of current energy efficiency and renewable energy program offerings available to Federal sites in the region. The level of detail, quality and currency of the data used in this market assessment varies significantly by Federal agency and energy efficiency service provider. Limited access to some Federal sites, limited availability of key points of contact, time/resource constraints, and other considerations limited the total number of Federal agencies and energy efficiency service providers participating in the survey.
Advanced Computing Annual Report 2024
In fiscal year (FY) 2024, the National Renewable Energy Laboratory (NREL) took a major leap forward with the completed full buildout of Kestrel, the Office of Energy Efficiency and Renewable Energy's newest high-performance computing (HPC) system. Kestrel is already supporting science across the portfolio, bringing roughly 44 petaflops of computing power, which is more than five times the capacity of our previous supercomputer, Eagle. By delivering greater GPU capacity, Kestrel enables faster progress in artificial intelligence (AI) and opens new avenues in energy research - from defining long-term planning scenarios to accommodate a growing power system to material discovery to improving energy efficiency in photovoltaics (PV). Across the portfolio, research is being accelerated by Kestrel's impressive power. During FY24, 427 projects and more than 700 researchers used NREL's HPC, supporting the U.S. Department of Energy's Office of Energy Efficiency and Renewable Energy across 13 funding areas. Through these collaborations, researchers produced more than 450 technical outputs, including 195 articles in peer-reviewed publications, pushing the boundaries of science and engineering. This year's report features new sections spotlighting the expanding roles of Artificial Intelligence and Accelerated Computing. We also introduce an early career section to celebrate the accomplishments of our up-and-coming researchers, whose pioneering work is shaping the future of energy. We hope you enjoy the new insights and discoveries highlighted in these pages.
BEopt-CA (Ex) -- A Tool for Optimal Integration of EE/DR/ES+PV in Existing California Homes. Cooperative Research and Development Final Report, CRADA Number CRD-11-429
Opportunities for combining energy efficiency, demand response, and energy storage with PV are often missed, because the required knowledge and expertise for these different technologies exist in separate organizations or individuals. Furthermore, there is a lack of quantitative tools to optimize energy efficiency, demand response and energy storage with PV, especially for existing buildings. Our goal is to develop a modeling tool, BEopt-CA (Ex), with capabilities to facilitate identification and implementation of a balanced integration of energy efficiency (EE), demand response (DR), and energy storage (ES) with photovoltaics (PV) within the residential retrofit market. To achieve this goal, we will adapt and extend an existing tool -- BEopt -- that is designed to identify optimal combinations of efficiency and PV in new home designs. In addition, we will develop multifamily residential modeling capabilities for use in California, to facilitate integration of distributed solar power into the grid in order to maximize its value to California ratepayers. The project is follow-on research that leverages previous California Solar Initiative RD&D investment in the BEopt software. BEopt facilitates finding the least cost combination of energy efficiency and renewables to support integrated DSM (iDSM) and Zero Net Energy (ZNE) in California residential buildings. However, BEopt is currently focused on modeling single-family houses and does not include satisfactory capabilities for modeling multifamily homes. The project brings BEopt's existing modeling and optimization capabilities to multifamily buildings, including duplexes, triplexes, townhouses, flats, and low-rise apartment buildings.
Advanced Energy Topics for Hill District Community Leaders [Slides]
Through Communities LEAP, a community coalition focused on the Hill District neighborhood of Pittsburgh is working with a technical assistance provider network led by the National Renewable Energy Laboratory (NREL). The coalition includes community organizations, nonprofits, the city government, and the utility. Technical assistance provides analysis and information to support Hill District stakeholders in their goals to create informed residential energy efficiency and renewable energy transition strategies that improve housing conditions and lower energy bills, incorporate energy efficiency and renewable energy strategies into existing, community-driven development efforts, and generate quality local jobs. The Advanced Energy Topics resource is intended to support Hill District community leaders with strategic planning on energy-related topics. The topics included are intended to serve as a technical reference for community leaders to help inform decision-making around energy. The Advanced Energy Topics resource was informed by engagement through the Communities LEAP pilot program with three Hill District Registered Community Organizations: the Hill District Collaborative, the Hill District Consensus Group, and the Hill Community Development Corporation.