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We analyze 36 years of global, hourly weather data (1980–2015) to quantify the covariability of solar and wind resources as a function of time and location, over multi-decadal time scales and up to continental length scales. Assuming minimal excess generation, lossless transmission, and no other generation sources, the analysis indicates that wind-heavy or solar-heavy U.S.-scale power generation portfolios could in principle provide ∼80% of recent total annual U.S. electricity demand. However, to reliably meet 100% of total annual electricity demand, seasonal cycles and unpredictable weather events require several weeks’ worth of energy storage and/or the installation of much more capacity of solar and wind power than is routinely necessary to meet peak demand. To obtain ∼80% reliability, solar-heavy wind/solar generation mixes require sufficient energy storage to overcome the daily solar cycle, whereas wind-heavy wind/solar generation mixes require continental-scale transmission to exploit the geographic diversity of wind. Policy and planning aimed at providing a reliable electricity supply must therefore rigorously consider constraints associated with the geophysical variability of the solar and wind resource—even over continental scales.
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This content will become publicly available on July 12, 2026
Carbon footprint and energy payback time of a micro wind turbine for urban decarbonization planning
Micro wind power systems may serve as a source of low-carbon electricity that can be integrated into cities as opposed to utility-scale wind turbines. However, the electricity generation performance of wind turbines of all capacities is highly dependent on conditions at an installation site, which can vary widely even within the same municipal region. We assess the life cycle greenhouse gas emissions (LCGHGE) and energy payback time of a novel microturbine of 2.4-kW capacity with location-specific environmental data. Potential electricity generation was modeled in the areas surrounding two US cities with ambitious decarbonization efforts and abundant wind energy resources in different climates: Austin, Texas and Minneapolis, Minnesota. The effects of system lifetime and hub height on the potential electricity generation were investigated, which identified trade-offs in higher electricity generation for taller turbines yet higher LCGHGE from greater amounts of materials needed. The LCGHGE of micro wind modeled for Austin and Minneapolis range from 53 to 293 g CO2eq/kWh, which is higher than utility-scale wind energy but still lower than fossil fuel sources of electricity. This study highlights the variability in the LCGHGE and energy payback time of micro wind power across locations, demonstrating the value of geospatial analyses for life cycle climate change impact estimates.
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- Award ID(s):
- 2316124
- PAR ID:
- 10616921
- Publisher / Repository:
- Springer Nature
- Date Published:
- Journal Name:
- Scientific Reports
- Volume:
- 15
- ISSN:
- 2045-2322
- Page Range / eLocation ID:
- 25237
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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