The Lawrence Berkeley National Laboratory (LBNL) released its annual wind energy data update in August 2020 and its annual utility-scale solar data update in November 2020.[1] [2] During a webinar on December 8, 2020 that compared the data from these studies, Mark Bollinger, one of the lead authors on the studies, concluded that solar is gaining ground on wind and natural gas in terms of projects seeking approval to connect to the grid.[3] On average, although solar is still more expensive, it delivers a greater net financial benefit to customers on average, according to Bollinger.
LBNL noted that new solar projects are benefiting from a growing trend toward "hybrid" combinations of renewable generation with battery storage which help with the “duck curve” challenge. This growing trend is helped by the federal investment tax credit, for which solar and battery hybrid projects are eligible while wind and battery pairings are not. However, whether wind or solar power is cheaper depends heavily on the region due to varying environmental conditions. The lab also emphasized that wind and solar still total no more than 10% of U.S. electricity output and there are several issues that could slow renewable market growth. Phaseouts of federal tax credits could significantly slow down market growth. Bollinger also added that in regions where the two power sources compete, "they tend to cannibalize their own market value” which could further slow down renewable growth.
[1] https://eta.lbl.gov/publications/wind-energy-technology-data-update
[2] https://eta.lbl.gov/publications/utility-scale-solar-data-update-2020