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Simpkins, Travis

Publications and source records attributed to Simpkins, Travis.

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↗

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↗

Portfolio Analysis of Renewable Energy Opportunities: Preprint

Time Warner Cable (TWC), now Charter Communications (CC), partnered with the National Renewable Energy Laboratory (NREL) to assess the technical and economic potential for solar photovoltaic (PV), wind, and ground-source heat-pump systems at 696 TWC facilities. NREL identified 306 sites where adding a renewable energy system would provide cost savings over the project life-cycle. In general, the top sites have some combination of high electricity rates ($0.16-$0.29/kWh), significant state incentives, and favorable net-metering policies. If all projects were implemented via third-party power purchase agreements, TWC/CC would save $37 million over 25 years and meet 10.5% of their energy consumption with renewable energy. This paper describes the portfolio screening methodology used to identify and prioritize renewable energy opportunities across the TWC sites, as well as a summary of the potential cost savings that may be realized by implementing these projects. This may provide a template for other companies interested in identifying and prioritizing renewable energy opportunities across a large number of geographically dispersed sites. Following this initial portfolio analysis, NREL will be conducting in-depth analysis of project development opportunities at ten sites and evaluating off-grid solutions that may enable carbon emission reduction and grid independence at select facilities.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

Catalyzing RE Project Development

This poster details how screenings done with REopt - NREL's software modeling platform for energy systems integration and optimization - are helping to catalyze the development of hundreds of megawatts of renewable energy.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

The Economic Potential of Two Nuclear-Renewable Hybrid Energy Systems

This report is one of a series of reports that investigate the technical and economic aspects of Nuclear-Renewable Hybrid Energy Systems. It provides the results of an analysis of two scenarios. The first is a Texas-synthetic gasoline scenario and the second is an Arizona-desalination scenario. 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 in which natural gas provides the energy.

10 SYNTHETIC FUELS↗