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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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This letter investigates a new class of optimal power flow problem for distribution systems, where elastic loads respond to real-time nodal prices by adjusting their demands. A fixed point iteration algorithm is suggested to identify an equilibrium. A concise criterion is devised to judge convergence.
To identify the impacts of regional electricity prices and building type on the economics of solar photovoltaic (PV) systems, 207 rate structures across 77 locations and 16 commercial building types were evaluated. Results for expected solar value are reported for each location and building type. Aggregated results are also reported, showing general trends across various impact categories.
The U.S. Environmental Protection Agency (EPA), in accordance with the RE-Powering America's Land initiative, selected the Price Landfill site in Pleasantville, New Jersey, for a feasibility study of renewable energy production. The National Renewable Energy Laboratory (NREL) provided technical assistance for this project. The purpose of this report is to assess the site for a possible photovoltaic (PV) system installation and estimate the cost, performance, and site impacts of different PV options. In addition, the report recommends financing options that could assist in the implementation of a PV system at the site. This study did not assess environmental conditions at the site.
The purpose of this document is to develop feedstock price values to be used in the United States (U.S.) Department of Energy’s (DOE) National Energy Technology Laboratory (NETL) energy systems studies. This version of the QGESS incorporates electricity and biomass fuel costs; it updates the coal costs; and it updates and expands the natural gas costs.
Accelerated market penetration of plug-in electric vehicles and deployment of grid-connected energy storage are restricted by the high cost of lithium-ion batteries. Research, development, and manufacturing are underway to lower material costs, enhance process efficiencies, and increase production volumes. A fraction of the battery cost may be recovered after vehicular service by reusing thebattery where it may have sufficient performance for other energy-storage applications. By extracting post-vehicle additional services and revenue from the battery, the total lifetime value of the battery is increased. The overall cost of energy-storage solutions for both primary (automotive) and secondary (grid) customer could be decreased. This techno-economic analysis of battery second useconsiders effects of battery degradation in both automotive and grid service, repurposing costs, balance-of-system costs, the value of aggregated energy-storage to commercial and industrial end users, and competitive technology. Batteries from plug-in electric vehicles can economically be used to serve the power quality and reliability needs of commercial and industrial end users. However, thevalue to the automotive battery owner is small (e.g., $20-$100/kWh) as declining future battery costs and other factors strongly affect salvage value. Repurposed automotive battery prices may range from $38/kWh to $132/kWh.
This paper describes how we calculate ISS resource shadow prices from the first-order cost minimization conditions using MESSOC and engineering cross-consumption models.
This powerpoint presentation to be presented at the World Renewable Energy Forum on May 17, 2012, in Denver, CO, discusses building-integrated photovoltaics (BIPV) in the residential section and includes an analysis of installed rooftop prices.
Brief summary of SSL Pricing and Efficacy Trend Analysis for Utility Program Planning report.
This poster provides a high-level overview of high penetrations of home energy managements systems under time-based electricity prices.
This poster presents an overview of evaluating the impact of price-responsive load on power systems using integrated transmission and distribution simulation.
Recent works have revealed that quantum extremal islands can contribute to the fine-grained entropy of black hole radiation reproducing the unitary Page curve. In this paper, we use these results to assess if an observer in de Sitter space can decode information hidden behind their cosmological horizon. By computing the fine-grained entropy of the Gibbons-Hawking radiation in a region where gravity is weak we find that this is possible, but the observer’s curiosity comes at a price. At the same time the island appears, which happens much earlier than the Page time, a singularity forms which the observer will eventually hit. We arrive at this conclusion by studying de Sitter space in Jackiw-Teitelboim gravity. We emphasize the role of the observer collecting radiation, breaking the thermal equilibrium studied so far in the literature. By analytically solving for the backreacted geometry we show how an island appears in this out-of-equilibrium state.
This study simulates the impacts of higher temperatures resulting from anthropogenic climate change on residential electricity consumption for California. Flexible temperature response functions are estimated by climate zone, which allow for differential effects of days in different temperature bins on households electricity consumption. The estimation uses a comprehensive household level dataset of electricity bills for California's three investor-owned utilities (Pacific Gas and Electric, San Diego Gas and Electric, and Southern California Edison). The results suggest that the temperature response varies greatly across climate zones. Simulation results using a downscaled version of the National Center for Atmospheric Research global circulation model suggest that holding population constant, total consumption for the households considered may increase by up to 55% by the end of the century. The study further simulates the impacts of higher electricity prices and different scenarios of population growth. Finally, simulations were conducted consistent with higher adoption of cooling equipment in areas which are not yet saturated, as well as gains in efficiency due to aggressive energy efficiency policies.
The global climate crisis is expected to reshape the energy generation landscape in the coming decades. Increasing integration of non-dispatchable renewable energy resources into energy infrastructures and markets creates uncertainty as well as new opportunities for flexible energy systems. To conduct proper economic evaluation of flexible energy systems, such as integrated energy systems (IES), advancements in modelling of market interactions, such as bidding, is crucial. This work presents a shortcut algorithm which uses two mixed integer linear programs to compute dispatch schedules (e.g., hourly power production targets) that are constrained by the resource's bid information and characteristics (e.g., minimum up and down times) based on historical locational marginal price (LMP) data. The proposed algorithm is approximately 100 times faster and uses orders of magnitude less data than a full production cost model (PCM). We find the shortcut simulator recapitulates generator dispatch signals for the Prescient PCM with approximately 4% error for the RTS-GMLC test system.
Realistic economic assessment of land-intensive alternative energy sources (e.g., solar, wind, and biofuels) requires information on land availability and price. Accordingly, we created a comprehensive, national-scale model of these parameters for the United States. For algae-based biofuel, a minimum of 1.04E+05 km2 of land is needed to meet the 2022 EISA target of 2.1E+10 gallons year-1. We locate and quantify land types best converted. A data-driven model calculates the incentive to sell and a fair compensation value (real estate and lost future income). 1.02E+6 km2 of low slope, non-protected land is relatively available including croplands, pasture/ grazing, and forests. Within this total there is 2.64E+5 km2 of shrub and barren land available. The Federal government has 7.68E+4 km2 available for lease. Targeting unproductive lands minimizes land costs and impacts to existing industries. However, shrub and barren lands are limited by resources (water) and logistics, so land conversion requires careful consideration.
Despite the recent development surrounding fast electric vehicle charging and ever growing interest in research, little is known as to how people in reality use Direct Current Fast Charger (DCFC) or how different pricing may affect their recharging behavior. Understanding the consumer behavior in DCFC usage is critical in successful deployment of DCFC. This paper analyzes real-world field data to examine DCFC usage in the U.S. In particular, it examines the effect of a flat-rate fee on the changes in the rate of charge. Furthermore, the result from regression analysis shows evidence that a flat-rate fee has a negative effect on efficient DCFC stations usage.
Global CO 2 emissions are increasing at about a 1.5% rate per year. Fossil fuel-based plants are one of the main contributors to this rise. In the power generation industry, fossil fuel plants are dominant, and many plants are under development. In this study, a natural gas combined cycle (NGCC) power plant with postcombustion capture using a leading water-lean solvent is considered. For optimal design and operating schedule, large-scale dynamic optimization is undertaken for net present value (NPV) optimization. The first principle dynamic model of NGCC is developed, including a model of the highly efficient H-class gas turbines. For computational tractability of the dynamic optimization problem, a reduced-order model is developed by using the Hankel singular value decomposition. A waterlean solvent, N-(2-ethoxyethyl)-3-morpholinopropan-1-amine, is used for carbon capture. A model of the capture system is developed in Aspen Plus, which is used to develop a reduced-order model by using ALAMO, a machine learning software. In addition, a reduced model of the CO 2 compression system with a dehydration unit is also considered. The integrated system is used for NPV optimization by using the Python-based PYOMO platform. The PCC process is analyzed for three configurations-conventional packed bed, rotating packed bed (RPB), and a combination of RPB and direct contact cooler. The NPV optimization is performed for 14 regional markets by considering year-long clustered and continuous locational marginal price data with a 1 h interval. Optimization results show that the PCC can achieve 90% CO 2 capture with a positive NPV for six regions. Sensitivity studies conducted by using the PCC configurations indicate that the process is economically feasible for 9 regions out of 14 regional electricity markets with NPV values in the range of 33−540 $MM.
Incorporation of divalent metal ions into an active site is a fundamental catalytic tool used by diverse enzymes. Divalent cations are used by protein kinases to both stabilize ATP binding and accelerate chemistry. Kinetic analysis establishes that Cyclin-dependent kinase 2 (CDK2) requires simultaneous binding of two Mg 2+ ions for catalysis of phosphoryl transfer. This tool, however, comes with a price: the rate-acceleration effects are opposed by an unavoidable rate-limiting consequence of the use of two Mg 2+ ions by CDK2. The essential metal ions stabilize ADP product binding and limit the overall rate of the reaction. We demonstrate that product release is rate limiting for activated CDK2 and evaluate the effects of the two catalytically essential Mg 2+ ions on the stability of the ADP product within the active site. We present two new crystal structures of CDK2 bound to ADP showing how the phosphate groups can be coordinated by either one or two Mg 2+ ions, with the occupancy of one site in a weaker equilibrium. Molecular dynamics simulations indicate that ADP phosphate mobility is more restricted when ADP is coordinated by two Mg 2+ ions compared to one. The structural similarity between the rigid ADP·2Mg product and the cooperatively assembled transition state provides a mechanistic rational for the rate-limiting ADP release that is observed. We demonstrate that although the simultaneous binding of two Mg 2+ ions is essential for efficient phosphoryl transfer, the presence of both Mg 2+ ions in the active site also cooperatively increases ADP affinity and opposes its release. Evolution of protein kinases must have involved careful tuning of the affinity for the second Mg 2+ ion in order to balance the needs to stabilize the chemical transition state and allow timely product release. The link between Mg 2+ site affinity and activity presents a chemical handle that may be used by regulatory factors as well as explain some mutational effects.
The visibility of pavement markings is one of the most critical factors for traffic safety, and a periodical assessment plan is crucial for maintaining this function. Traditional assessment methods, such as visual windshield surveys or manual testing using handheld devices, are unsafe, time-consuming, and labor-intensive. In recent years, transportation agencies have begun to adopt the use of mobile retroreflectivity units (MRUs) for condition assessment of pavement markings. MRUs, different from other manual methods, can be utilized to collect large-scale retroreflectivity data in an efficient manner. However, no relevant research has yet proposed a mathematical optimization model for arranging the evaluation schedule and paths of MRUs. This study aims to propose a MRU routing model, and an efficient solution methodology. A branch-and-price algorithm, including column generation and branch-and-bound, was implemented. Computational experiments have been conducted based on actual tasks from the Florida MRU program for validation. In conclusion, results show that the proposed solution methodology with a set partitioning model in this study not only finds the optimal solution for problems with tasks less than 60, but also effectively narrows the solution gap to be within 1.0% for problems with tasks less than 131.