On the Complementary Variability of the Solar and Wind Resources

The variability of large-scale, distributed wind and PV generation across the continental US is evaluated and contrasted. We analyze single year of hourly-interval, time-synchronous wind power production simulated from ERA-5 and PV production simulated with SolarAnywhere™. We examine the way in which the variability (as identified with a COV) of each resource changes with both temporal scale (time-averaging intervals from 1-8760 hours), spatial scale (spatial-averaging from 10 km<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> to 8 million km<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup>) and location (across the CONUS). We empirically show that, although the variability of solar power is much more significant than that of wind at sub-24-h timescale, wind exhibits significantly more variability than solar at all timescales longer than a day. We show that spatial averaging reduces the variability of the aggregate wind resource much more so than for solar. The implications with respect to the energy transition are discussed.