U.S. solar installations reached a record high in 2020 as favorable economics, supportive policies and strong demand in the second half of the year offset the impact of the coronavirus pandemic. Installations grew 43% year over year, reaching a record 19.2 gigawatts of new capacity, according to a report released Tuesday from the Solar Energy Industries Association and Wood Mackenzie. In the fourth quarter alone, the U.S. added just over 8 GW of capacity a quarterly record. That's more than the capacity added in all of 2015, which was 7.5 GW. California, Texas and Florida were the top three states for annual solar additions for the second year running. Virginia and North Carolina rounded out the top five. In the U.S., solar represented 43% of all new electricity generating capacity added in 2020, its largest ever share of new generating capacity. Solar is also the cheapest form of new power in many places. "Residential solar sales continue to exceed expectations as loan providers roll out attractive products, interest in home improvement surges, and customers suffering through power outages from extreme weather events seek energy resilience," the report said. The report also looked for the first time at growth forecasts through 2030, projecting that the U.S. solar market will quadruple from current levels by the end of the decade. The growth is expected to be spread across markets as customers, utilities, states and corporations push to decarbonize the grid.