The United States could reliably meet about 80 percent of its electricity demand with solar and wind power generation, according to scientists at the University of California, Irvine; the California Institute of Technology; and the Carnegie Institution for Science.
However, meeting 100 percent of electricity demand with only solar and wind energy would require storing several weeks' worth of electricity to compensate for the natural variability of these two resources, the researchers said.
"The sun sets, and the wind doesn't always blow," noted Steven Davis, UCI associate professor of Earth system science and co-author of a renewable energy study published today in the journal Energy & Environmental Science. "If we want a reliable power system based on these resources, how do we deal with their daily and seasonal changes?"
The team analyzed 36 years of hourly U.S. weather data (1980 to 2015) to understand the fundamental geophysical barriers to supplying electricity with only solar and wind energy.
"We looked at the variability of solar and wind energy over both time and space and compared that to U.S. electricity demand," Davis said. "What we found is that we could reliably get around 80 percent of our electricity from these sources by building either a continental-scale transmission network or facilities that could store 12 hours' worth of the nation's electricity demand."