American rooftop solar power is growing at a stunning rate, a new study finds, with solar capacity increasing 19% in 2021.
The United States now has 121.4 gigawatts of solar photovoltaic capacity, enough to power 23 million homes, up from just 0.34 gigawatts in 2008, according to the Department of Energy.
Cities located in the Southwest and on the West Coast are, by and large, way ahead of their northern and eastern counterparts at getting solar panels on rooftops, according to a new study from Environment America Research & Policy Center, a think tank, and Frontier Group, a research organization affiliated with the Public Interest Network.
“The amount of solar power installed in just nine U.S. cities exceeds the amount installed in the entire United States 10 years ago,” the report, titled “Shining Cities 2022,” found. In fact, 15 of the 56 cities included in the study increased their solar capacity tenfold since 2014.
Solar installers place solar panels on the roof of a home in San Diego in 2016. (Mike Blake/Reuters)
According to the Intergovernmental Panel on Climate Change, clean sources of energy such as wind and solar power must account for the vast majority of electricity within the next few decades to avoid catastrophic climate change.
The top five per capita solar power producers are Honolulu, Las Vegas, San Diego, Albuquerque and San Jose, Calif., in that order. The rest of the top 19 cities include several more in California (Los Angeles, Sacramento and Riverside); a few from nearby states, including Phoenix and Salt Lake City; and several from the South, such as New Orleans. The only cities on the list of the top 19 producers that are not located in the West or Southwest are Burlington, Vt. (in seventh place), Washington, D.C. (10th), Indianapolis (16th), Hartford, Conn. (17th), Newark, N.J., (18th) and Charleston, S.C. (19th).
There are a variety of factors that determine the rate of solar deployment, including state and local policies, energy prices, climate and housing stock, among others. Southern and Western cities may lead in part because of their abundant sunshine, leaving ample room for rooftop or backyard solar arrays. By contrast, cities in the Northeast and Midwest may lag partly due to rainier weather.
Nationally, the changing economics of solar power have driven the sector’s explosive growth. The average cost of solar panels has dropped 70% since 2014, according to the Department of Energy.
The 102-acre, 15-megawatt Solar Array II Generating Station at Nellis Air Force Base in 2016 in Las Vegas. (Ethan Miller/Getty Images)
Cost is also a reason that some states have gone solar much faster than others. Hawaii and California have the highest and third-highest electricity prices in the country, respectively, giving homeowners more incentive to reduce their bills by …….