The former president, who was 11 when his boyhood home got running water after his father installed a windmill, did not need convincing and became deeply involved with the project, writing notes in the margins of the lease agreement and visiting the site regularly.

Mr. Carter, Jason Carter recalled this week, regularly sent pictures of the construction on the farmland, which he often passed during walks here with his wife, Rosalynn.

“When I told people we were getting solar panels, they said, ‘In Plains?’” said Jan Williams, who runs the Plains Historic Inn and helps to organize Mr. Carter’s regular Sunday school classes, which remain a draw for tourists. “They say, ‘Well, that’s because of Jimmy Carter.’ It is because of Jimmy Carter. Plains is all because of Jimmy Carter.”

The Plains project, limited in size, according to Mr. Carter and SolAmerica, because of what existing infrastructure could handle, is far from the first solar effort in Georgia. But it is among the highest-profile projects in a state where, after years of reluctance, regulators have demanded that the predominant utility company place a greater emphasis on solar power.

In this state, and in other parts of the country where many residents are unconvinced of climate change, renewable energy supporters have often tailored their pitches to focus on economic benefits. A plurality of Georgia’s electric generation jobs are in solar, according to the Department of Energy.

“The old politicized arguments about renewable energy being for coastal liberals just don’t play anymore in parts of the country where they’re experiencing firsthand the economic benefits of renewable energy development and job creation,” said Jodie Van Horn, the director of the Sierra Club’s Ready for 100 campaign, which pushes American cities to commit to entirely renewable energy offerings.

Renewable energy supporters do not have to ignore climate change arguments entirely, though. In 2014 in Sumter County, which includes Plains, 62 percent of residents believed that global warming was happening, according to an estimate from the Yale Program on Climate Change Communication. That is slightly higher than some counties in metropolitan Atlanta.