Gian Porro

U.S. Renewable Energy Technical Potentials: A GIS-Based Analysis

This report presents the state-level results of a spatial analysis effort calculating energy technical potential, reported in square kilometers of available land, megawatts of capacity, and gigawatt-hours of generation, for six different renewable technologies. For this analysis, the system specific power density (or equivalent), efficiency (capacity factor), and land-use constraints were identified for each technology using independent research, published research, and professional contacts. This report also presents technical potential findings from previous reports.

Renewable Electricity Futures for the United States

This paper highlights the key results from the Renewable Electricity (RE) Futures Study. It is a detailed consideration of renewable electricity in the United States. The paper focuses on technical issues related to the operability of the U.S. electricity grid and provides initial answers to important questions about the integration of high penetrations of renewable electricity technologies from a national perspective. The results indicate that the future U.S. electricity system that is largely powered by renewable sources is possible and the further work is warranted to investigate this clean generation pathway. The central conclusion of the analysis is that renewable electricity generation from technologies that are commercially available today, in combination with a more flexible electric system, is more than adequate to supply 80% of the total U.S. electricity generation in 2050 while meeting electricity demand on an hourly basis in every region of the United States.

2015 Standard Scenarios Annual Report: U.S. Electric Sector Scenario Exploration

This report is one of several products resulting from an initial effort to provide a consistent set of technology cost and performance data and to define a conceptual and consistent scenario framework that can be used in the National Renewable Energy Laboratory’s (NREL’s) future analyses. The long-term objective of this effort is to identify a range of possible futures of the U.S. electricity sector in which to consider specific energy system issues through (1) defining a set of prospective scenarios that bound ranges of key technology, market, and policy assumptions and (2) assessing these scenarios in NREL’s market models to understand the range of resulting outcomes, including energy technology deployment and production, energy prices, and carbon dioxide (CO2) emissions.

Implications of a PTC Extension on U.S. Wind Deployment

This analysis explores the potential effects of wind production tax credit expiration and various extension scenarios on future wind deployment with the Regional Energy Deployment System (ReEDS), a model of the U.S. electricity sector. The analysis does not estimate the potential implications on government tax revenue associated with the PTC. Key findings include: Under a scenario in which the PTC is not extended and all other policies remain unchanged, wind capacity additions are expected to be between 3 and 5 GW per year from 2013-2020; PTC extension options that ramp-down from the current level to zero-credit by year-end 2022 appear to be insufficient to support deployment at the recent historical average; Extending the PTC at its historical level may provide the best opportunity to support deployment consistent with recent levels across a range of potential market conditions; it therefore may also provide the best opportunity to sustain wind power installation and manufacturing sector at current levels.

ReEDS Modeling of the President’s 2020 U.S. Renewable Electricity Generation Goal (Presentation)

President Obama announced in 2012 an Administration Goal for the United States to double aggregate renewable electricity generation from wind, solar, and geothermal sources by 2020. This analysis, using the Regional Energy Deployment System (ReEDS) model, explores a full range of future renewable deployment scenarios out to 2020 to assess progress and outlook toward this goal. Under all modeled conditions, consisting of 21 scenarios, the Administration Goal is met before 2020, and as early as 2015.