On Monday, which happened to be Earth Day, the Joe Biden administration announced that it’s awarding $7 billion in grants for the installation of residential solar projects. The money, which is from the Inflation Reduction Act, is meant to help more than 900,000 low-income and disadvantaged households benefit from solar energy, including by lowering their electric bills. With the cost of installing solar panels relatively high, the federal Solar for All effort aims to bring the decades-old technology further into the mainstream.

Solar cells were first put into practical use during the space race of the 1950s. John Perlin, author of the book “Let It Shine: The 6,000 Year Story of Solar Energy,” said the cells became widespread in powering satellites. But not in homes.

“The government at the time was promoting nuclear power as the panacea for future energy needs. And solar was put on the back burner for a very long time,” said Perlin.

Now it’s on the front burner. But as of 2020, only 4% of single-family homes in the U.S. had solar panels installed. 

Donnel Baird, CEO of the clean energy company BlocPower, said cost is a big reason. He estimates that installation can run between $5,000 and $25,000, which can include updating parts of your house. 

“Do you need a new roof? Because you don’t want to put new solar panels on an old roof,” Baird said.

Solar panels have had early adopters, he added. “But then there’s this, like, valley of death before you get to the mass market. And that’s kind of where we are.”

Baird said solar is on the way out of that valley, but there are still challenges, even with a big investment like the one announced Monday. One is limited technical know-how. 

“We are missing a generation of skilled construction workers in America and in Europe,” Baird said.

Another issue is trust, especially in low-income neighborhoods, said Anya Schoolman, who leads the nonprofit Solar United Neighbors. She also advised some of the Biden administration’s solar grantees on their applications.

“You’re working in communities who’ve been ripped off for years. Most people are inclined not to believe, you know, ‘Hey, I have a free solar system. And you can save money for the next 25 years,'” Schoolman said.

She said building that kind of trust takes time, and a lot of people want to know someone who has a solar panel before they get one too.