The PSC has approved permits for Alliant Energy to undertake a massive solar project.

With the commission’s unanimous vote in hand, Alliant will start on the first four of six solar farms totaling 675 megawatts. This will take the company two-thirds of the way toward its goal to integrate more than a gigawatt — 1,000 megawatts — of solar capacity into its portfolio over the next four years.

RENEW Wisconsin is calling it “the most significant advance yet towards a zero-carbon future in Wisconsin.”

The projects, two of which still need PSC approval for construction, will be located in Rock, Grant, Jefferson, Sheboygan, Richland and Wood counties. The PSC unanimously approved the Wood County solar project in January. The Grant and Sheboygan county projects are still under review due to the size of their generating capacity, PSC noted in a release.

This first wave of projects will be fully operational in 2023. Then, roughly 13 percent of the electricity sold to Alliant customers will come from a solar farm, according to RENEW. This puts Alliant on course to own and operate almost one-half of the state’s solar capacity by 2024. Solar accounts for 16 percent of the state’s electricity sales.

“We salute Alliant for committing to this bold pivot towards zero-carbon power generated in Wisconsin,” said RENEW Executive Director Heather Allen. “We are hopeful the Public Service Commission’s decision will encourage other utilities to go big on solar power.”

The estimated total cost of the solar projects is $887 million. Alliant’s customers will see savings of about $127 million due to the retirement of higher cost coal-fired generation. Prior to yesterday’s decision, the PSC had approved 1,078 megawatts of utility-scale solar generation in Wisconsin.

“As our state and utilities continue to pursue shared goals of ensuring that all electricity consumed in Wisconsin be carbon-free by 2050, projects like these will continue to allow for the closure of coal-burning power plants while we ensure safe, reliable, and affordable service for customers,” said PSC Chairperson Rebecca Cameron Valcq.