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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 127 records · Page 7
All sourcesNASA NTRSDOE OSTI
DOE OSTI2026

Solar Thermal Energy Planner (STEP 1): A New Decision Support Tool for Solar Industrial Process Heat Applications

Solar thermal technologies are a promising technology to supply low-cost thermal energy to industrial processes, but there are often significant barriers to entry to industrial owners considering these technologies for their energy demands. To overcome this barrier and convey economic value to customers, NREL and Sandia National Laboratories developed Solar Thermal Energy Planner (STEP 1), a new web-based decision support tool for solar industrial process heat systems. At SolarPACES 2024, the STEP 1 tool was still under development; progress, methodologies, and a preliminary case study was presented. With the STEP 1 tool launch in May 2025, in this work, the initial version of the full public tool will be presented with demonstrations of its capabilities using a few case studies. First, the user's process heat needs such as location, process media (e.g., steam, air), process temperature, land availability, electricity and fuel costs, among other parameters. STEP 1 features a mapping interface that allows users to draw land and roof boundaries. The process media and temperature inform technology selection criteria modules that determine the appropriate solar thermal collection technologies, as well as congruent heat transfer media (e.g., hot water, oil, salt). Once the solar thermal technology selected, its nominal thermal production for the given site is characterized using NREL's System Advisor Model (SAM). Then, a modified version of NREL's REopt optimal sizing and dispatch optimization tool determines cost-optimal sizing. Within minutes, the user receives the results of the technoeconomics analysis, including the size and performance of the cost-optimal solar-plus-storage system. The cost of the system is compared to business-as-usual (e.g., an existing, standalone natural gas boiler). Users can download key results to store for sensitivity analyses. Examples of flat plate collector, parabolic trough, and molten salt tower applications with and without PV hybridization for different industrial facility types are presented in this work. The STEP 1 tool aims to reduce barriers to the adoption of solar heating solutions stemming from a lack of familiarity and technical background with solar system design options and costs among industry stakeholders.

14 SOLAR ENERGY↗
DOE OSTI2023

Distributed clean energy opportunities for US oil refinery operations

The oil and gas industry is increasingly seeking operational improvements to reduce costs and emissions while improving resilience. This study describes techno-economic analysis of opportunities for distributed energy resources that could be integrated to support oil and gas companies’ economic, environmental, and energy resiliency goals. Specifically, the analysis evaluates solar photovoltaics, wind turbines, battery energy storage, landfill gas, biomass, municipal solid waste-to-energy, solar steam for process heat, combined heat and power, and electrolyzers for hydrogen production at two hypothetical refineries, one located in Louisiana and the other in southern California. These technologies could reduce the sites’ consumption of grid electricity and/or natural gas and thus can help reduce emissions. This study employs the ReOPT tool and System Advisor Model to evaluate the techno-economic potential for clean energy technologies to support refineries in achieving energy goals, including energy cost savings, resiliency, and emissions reductions. Results indicate that the associated costs of emissions reductions via several distributed clean energy technologies are competitive with other emissions reduction strategies such as energy efficiency, reducing flaring, direct carbon capture and sequestration, and markets under certain conditions. There are also cost beneficial opportunities for the use of renewable energy for refining, especially for resilience, depending on local conditions such as resources and utility costs.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2019

Behind-the-Meter Solar + Storage Modeling Tool Comparison

Several techno-economic models exist to evaluate solar PV plus battery storage opportunities for behind-the-meter, commercial application. This tool comparison evaluates the methodological differences between several solar plus storage modeling tools and employs a case study to compare their outputs. The tools selected for comparison include NREL's REopt Lite, NREL's System Advisor Model (SAM), Homer Energy's Homer Grid, Geli ESyst, EPRI StorageVET, and LBL's DER-CAM. The comparison focuses on each tool's simulation and optimization capabilities, PV and battery performance modeling, dispatch strategies, and economic model assumptions and calculations, with brief mention of additional capabilities outside the scope of behind-the-meter PV and battery storage. This report describes the case study's tool inputs and outputs and dives into the differences in assumptions, methodologies, and capabilities between tools.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2020

Metrics and Analytical Frameworks for Valuing Energy Efficiency and Distributed Energy Resources in the Built Environment: Preprint

This paper summarizes efforts to develop new—and enhance existing—analytical frameworks and metrics to quantify the value that grid-interactive efficient homes with solar (GEB-solar homes) can provide. Industry is working to characterize and understand these capabilities and benefits, but existing analytical frameworks for evaluating energy efficiency (EE) are often siloed from those that evaluate distributed energy resources (DERs). Five metrics were adapted from an extensive literature review and applied to case studies of a modeled home in Riverside, California: ramp up/down, cover factor demand/supply, and curtailable load. Eight different technology scenarios were analyzed using a more tightly connected suite of building-to-grid models (BEopt, REopt, ReEDS, and PLEXOS). Additionally, an initial version of the Cambium tool was developed, characterizing the marginal prices and emissions from NREL’s 2018 Standard Scenarios. These grid costs were extended to a time-varying proxy retail rate and applied as part of a new grid alignment metric. In the results, a more integrated combination of GEB-solar technologies led to a higher cover factor demand—the percentage of gross home load covered by on-site solar—however, a benchmark was required to determine what range of cover factor was “best” for given grid conditions. To that end, a grid alignment cost metric was applied to the case study scenarios. The average cost to serve the net load of the home decreased from a median of ~$0.24/kWh to ~$0.10/kWh when the most integrated technology scenario was optimized towards the grid pricing proxy versus the time-of-use (TOU) rate.

41 EE - Solar Energy Technologies Office (EE-4S)↗
DOE OSTI2022

National Community Solar Partnership Multifamily Affordable Housing Portfolio Screening Approach

Community solar offers multiple benefits to providers and residents of multifamily affordable housing (MFAH), including access to affordable renewable energy for low- and moderate-income households, tax credits and other financial benefits for property owners, and increased community resilience when paired with energy storage. Even so, MFAH providers interested in realizing these benefits may need support to identify where to start or how to expand and accelerate solar deployment across their property portfolios once they have completed their first few installations. This fact sheet describes a portfolio screening approach for MFAH providers to evaluate their multi-state building portfolios for community solar project viability. The approach was developed by the National Renewable Energy Laboratory as part of its support for the National Community Solar Partnership (NCSP) MFAH Collaborative. By utilizing NREL's companion Policy Screening Workbook in conjunction with the web-based tools PVWatts® Calculator and REopt™ (Renewable Energy Integration and Optimization), MFAH providers can take a data-informed approach to identifying and prioritizing buildings in their portfolios that are most amenable to community solar development.

community solar↗
DOE OSTI2023

Hydrogen Energy Storage System at Borrego Springs Towards an H2 Enabled 100 Renewable Microgrid

San Diego Gas & Electric's Borrego Springs Microgrid is one of the largest microgrids in the USA, serving 2500 residential customers, 300 commercial and industrial customers, and has a peak demand of approximately 14 MW. This microgrid is located at the end of a long transmission line, and is subjected to extreme weather events like storms, wildfires, and flooding, which frequently cause grid outages. The microgrid currently relies on 3.65 MW of diesel-powered generators to provide grid-forming services during these outages, which results in greenhouse gas and criteria pollutant emissions. However, the microgrid has access to approximately 37 MW of installed solar generation and struggles with overgeneration and curtailment. 1.5 MW/4.5 MWh of grid-scale batteries have been installed to capture some the overgeneration and provide resiliency, but a longer-duration low-greenhouse gas emission energy storage solution is needed. In our project, the team will evaluate in the lab and demonstrate in the field a grid-forming fuel cell inverter that can provide grid-forming services while utilizing hydrogen's energy storage scalability. We will first utilize NREL's Renewable Energy Integration and Optimization (REopt) platform to perform analyses on future microgrid scenarios that use hydrogen assets to reduce or eliminate the need for diesel backup generators. We will then evaluate the grid-forming inverter through power hardware-in-the-loop and controller hardware-in-the-loop experiments at ARIES, and de-risk the field deployment and operation of hydrogen assets in the microgrid setting. Finally, this project will demonstrate the operation of the fuel cell inverter and updated microgrid controller by operating in grid-forming mode in the Borrego Springs microgrid.

Borrego Springs↗
DOE OSTI2024

Merefa Community Microgrid: Supporting Distributed Energy Resource Deployment in Ukraine

A conceptual design is described for a community microgrid in Ukraine. Microgrid resources include solar photovoltaics, battery energy storage, and conventional natural gas fueled reciprocating engine generators. The conceptual architecture was informed by the microgrid developer, NREL subject matter experts, and the application of REopt, an NREL-developed software tool created for identification of least-cost combination of resources for achieving cost savings, resilience, and renewable energy goals. This fact sheet is a summary of a previously published technical report; see NREL/TP-7A40-89527, which includes conceptual architecture, estimates of key summary financial metrics, and sequence of operations.

battery storage↗
DOE OSTI2024

Hydrogen Energy Storage System at Borrego Springs Towards an H2 Enabled 100% Renewable Microgrid

San Diego Gas & Electric's Borrego Springs Microgrid is one of the largest microgrids in the USA, serving 2500 residential customers, 300 commercial and industrial customers, and has a peak demand of approximately 14 MW. This microgrid is located at the end of a long transmission line, and is subjected to extreme weather events like storms, wildfires, and flooding, which frequently cause grid outages. The microgrid currently relies on 3.65 MW of diesel-powered generators to provide grid-forming services during these outages, which results in greenhouse gas and criteria pollutant emissions. However, the microgrid has access to approximately 37 MW of installed solar generation and struggles with overgeneration and curtailment. 1.5 MW/4.5 MWh of grid-scale batteries have been installed to capture some the overgeneration and provide resiliency, but a longer-duration low-greenhouse gas emission energy storage solution is needed. In our project, the team will evaluate in the lab and demonstrate in the field a grid-forming fuel cell inverter that can provide grid-forming services while utilizing hydrogen's energy storage scalability. We will first utilize NREL's Renewable Energy Integration and Optimization (REopt) platform to perform analyses on future microgrid scenarios that use hydrogen assets to reduce or eliminate the need for diesel backup generators. We will then evaluate the grid-forming inverter through power hardware-in-the-loop and controller hardware-in-the-loop experiments at ARIES, and de-risk the field deployment and operation of hydrogen assets in the microgrid setting. Finally, this project will demonstrate the operation of the fuel cell inverter and updated microgrid controller by operating in grid-forming mode in the Borrego Springs microgrid.

blackstart with fuel cells↗
DOE OSTI2018

Solar plus: A review of the end-user economics of solar PV integration with storage and load control in residential buildings

Batteries and load control devices can increase the value of distributed solar photovoltaics (PV) from multiple perspectives - end-user, utility, and social. This review paper summarizes the end-user economics of battery and load control technologies that increase the value of PV by controlling and temporally shifting PV output, an approach referred to as 'solar plus.' Solar plus can increase on-site PV use. The literature shows that these values justify the incremental costs of solar plus devices for a wide variety of technologies, geographies, and customer load profiles, especially for customers in three rate structure contexts: where PV is sold to the grid at a lower value than the customer's retail rate, in time-of-use rates where peak periods do not coincide with PV output, and in demand charge rates where load peaks do not coincide with PV output. Rate structure and policy reform may be necessary to ensure that increasing solar plus deployment provides both end-user and system-level benefits.

14 SOLAR ENERGY↗
DOE OSTI2016

Optimal Sizing of a Solar-Plus-Storage System for Utility Bill Savings and Resiliency Benefits

Solar-plus-storage systems can achieve significant utility savings in behind-the-meter deployments in buildings, campuses, or industrial sites. Common applications include demand charge reduction, energy arbitrage, time-shifting of excess photovoltaic (PV) production, and selling ancillary services to the utility grid. These systems can also offer some energy resiliency during grid outages. It is often difficult to quantify the amount of resiliency that these systems can provide, however, and this benefit is often undervalued or omitted during the design process. We propose a method for estimating the resiliency that a solar-plus-storage system can provide at a given location. We then present an optimization model that can optimally size the system components to minimize the lifecycle cost of electricity to the site, including the costs incurred during grid outages. The results show that including the value of resiliency during the feasibility stage can result in larger systems and increased resiliency.

14 SOLAR ENERGY↗
DOE OSTI2016

A Statistical Analysis of the Economic Drivers of Battery Energy Storage in Commercial Buildings: Preprint

There is significant interest in using battery energy storage systems (BESS) to reduce peak demand charges, and therefore the life cycle cost of electricity, in commercial buildings. This paper explores the drivers of economic viability of BESS in commercial buildings through statistical analysis. A sample population of buildings was generated, a techno-economic optimization model was used to size and dispatch the BESS, and the resulting optimal BESS sizes were analyzed for relevant predictor variables. Explanatory regression analyses were used to demonstrate that peak demand charges are the most significant predictor of an economically viable battery, and that the shape of the load profile is the most significant predictor of the size of the battery.

25 ENERGY STORAGE↗
DOE OSTI2018

Coordinated Optimization of Multiservice Dispatch for Energy Storage Systems with Degradation Model for Utility Applications

The rapid development of energy storage technologies is motivating researchers to understand the possible value of energy storage. This paper evaluates the multiservice dispatch of distribution-sited energy storage systems with realistic degradation models by integrating a multiservice optimization model with a distribution system simulator. This work attempts to define the theoretical value energy storage can bring when multiple value streams are considered in the modeling environment. Use cases presented in this paper deliver multiple services to both distribution and transmission stakeholders that can provide positive net value to the electricity system under prevailing energy storage cost structures. Furthermore, this work was performed in collaboration with a distribution utility to help utility personnel understand the value distributed energy storage can provide by examining different utility use cases without considering implementation costs.

24 POWER TRANSMISSION AND DISTRIBUTION↗
DOE OSTI2016

New York Solar Smart DG Hub-Resilient Solar Project: Economic and Resiliency Impact of PV and Storage on New York Critical Infrastructure

Resilient PV, which is solar paired with storage ('solar-plus-storage'), provides value both during normal grid operation and power outages as opposed to traditional solar PV, which functions only when the electric grid is operating. During normal grid operations, resilient PV systems help host sites generate revenue and/or reduce electricity bill charges. During grid outages, resilient PV provides critical emergency power that can help people in need and ease demand on emergency fuel supplies. The combination of grid interruptions during recent storms, the proliferation of solar PV, and the growing deployment of battery storage technologies has generated significant interest in using these assets for both economic and resiliency benefits. This report analyzes the technical and economic viability for resilient PV on three critical infrastructure sites in New York City (NYC): a school that is part of a coastal storm shelter system, a fire station, and a NYCHA senior center that serves as a cooling center during heat emergencies. This analysis differs from previous solar-plus-storage studies by placing a monetary value on resiliency and thus, in essence, modeling a new revenue stream for the avoided cost of a power outage. Analysis results show that resilient PV is economically viable for NYC's critical infrastructure and that it may be similarly beneficial to other commercial buildings across the city. This report will help city building owners, managers, and policymakers better understand the economic and resiliency benefits of resilient PV. As NYC fortifies its building stock against future storms of increasing severity, resilient PV can play an important role in disaster response and recovery while also supporting city greenhouse gas emission reduction targets and relieving stress to the electric grid from growing power demands.

14 SOLAR ENERGY↗
DOE OSTI2016

The Economic Potential of Two Nuclear-Renewable Hybrid Energy Systems

Tightly coupled nuclear-renewable hybrid energy systems (N-R HESs) are an option that can generate zero-carbon, dispatchable electricity and provide zero-carbon energy for industrial processes at a lower cost than alternatives. N-R HESs are defined as systems that are managed by a single entity and link a nuclear reactor that generates heat, a thermal power cycle for heat to electricity conversion, at least one renewable energy source, and an industrial process that uses thermal and/or electrical energy. This report provides results of an analysis of two N-R HES scenarios. The first is a Texas-synthetic gasoline scenario that includes four subsystems: a nuclear reactor, thermal power cycle, wind power plant, and synthetic gasoline production technology. The second is an Arizona-desalination scenario with its four subsystems a nuclear reactor, thermal power cycle, solar photovoltaics, and a desalination plant. The analysis focuses on the economics of the N-R HESs and how they compare to other options, including configurations without all the subsystems in each N-R HES and alternatives where the energy is provided by natural gas.

14 SOLAR ENERGY↗
DOE OSTI2016

The Economic Potential of Three Nuclear-Renewable Hybrid Energy Systems Providing Thermal Energy to Industry

This report is one of a series of reports that Idaho National Laboratory and National Renewable Energy Laboratory are producing to investigate the technical and economic aspects of nuclear-renewable hybrid energy systems (N-R HESs). Previous reports provided results of an analysis of two N-R HES scenarios. This report builds that analysis with a Texas-synthetic gasoline scenario providing the basis in which the N-R HES sells heat directly to an industrial customer. Subsystems were included that convert electricity to heat, thus allowing the renewable energy subsystem to generate heat and benefit from that revenue stream. Nuclear and renewable energy sources are important to consider in the energy sector's evolution because both are considered to be clean and non-carbon-emitting energy sources.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2017

The Economic Potential of Nuclear-Renewable Hybrid Energy Systems Producing Hydrogen

This report is one in a series of reports that Idaho National Laboratory and the Joint Institute for Strategic Energy Analysis are publishing that address the technical and economic aspects of nuclear-renewable hybrid energy systems (N-R HESs). This report discusses an analysis of the economic potential of a tightly coupled N-R HES that produces electricity and hydrogen. Both low and high temperature electrolysis options are considered in the analysis. Low-temperature electrolysis requires only electricity to convert water to hydrogen. High temperature electrolysis requires less electricity because it uses both electricity and heat to provide the energy necessary to electrolyze water. The study finds that, to be profitable, the examined high-temperature electrosis and low-temperature electrosis N-R HES configurations that produce hydrogen require higher electricity prices, more electricity price volatility, higher natural gas prices, or higher capacity payments than the reference case values of these parameters considered in this analysis.

08 HYDROGEN↗
DOE OSTI2017

Solar Plus: A Holistic Approach to Distributed Solar PV

Solar 'plus' refers to an emerging approach to distributed solar photovoltaic (PV) deployment that uses energy storage and controllable devices to optimize customer economics. The solar plus approach increases customer system value through technologies such as electric batteries, smart domestic water heaters, smart air-conditioner (AC) units, and electric vehicles We use an NREL optimization model to explore the customer-side economics of solar plus under various utility rate structures and net metering rates. We explore optimal solar plus applications in five case studies with different net metering rates and rate structures. The model deploys different configurations of PV, batteries, smart domestic water heaters, and smart AC units in response to different rate structures and customer load profiles. The results indicate that solar plus improves the customer economics of PV and may mitigate some of the negative impacts of evolving rate structures on PV economics. Solar plus may become an increasingly viable model for optimizing PV customer economics in an evolving rate environment.

14 SOLAR ENERGY↗