Wisconsin regulators have approved Alliant Energy’s plans to spend nearly $1 billion on new solar plants as part of the Madison-based utility’s plans to phase out coal-fired generators.
The Public Service Commission agreed unanimously Thursday to authorize Alliant to purchase six solar farms with a combined capacity of 675 megawatts, enough to power about 175,000 typical Wisconsin homes.
It is the largest single renewable energy investment to date in Wisconsin.
“This is an important step today in where, not just this state, but where the country is going,” said Commissioner Ellen Nowak. But she cautioned, “We are moving exceedingly fast in this step. We don’t know a lot yet about some of the unintended consequences.”
PSC Chair Rebecca Valcq noted the approval came on the 51st anniversary of Earth Day.
“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,” Valcq said in a statement.
Renew Wisconsin hailed the decision as “the most significant advance yet towards a zero-carbon future in Wisconsin.”
David de Leon, president of Alliant’s Wisconsin utility, said the decision will ensure reliable, environmentally friendly energy and promote economic growth.
“We are proud of the sustainable path we’re on,” de Leon said in a statement. “These projects will create new construction jobs and provide revenues to local communities and landowners for decades to come.”
The six plants — under development in Grant, Jefferson, Richland, Rock, Sheboygan and Wood counties — are the first phase in Alliant’s plans to add nearly 1,100 megawatts of solar capacity by 2024. Alliant last month filed a separate application to acquire an additional six solar farms for about $515 million.
The PSC previously approved construction of one of the projects — a 150-megawatt plant in Wood County — and is separately considering applications for two others. The other three plants — in Jefferson, Richland and Rock counties — are smaller than 100 megawatts and require only local approval.
Organizations including the Sierra Club, trade unions and Wisconsin Manufacturers and Commerce, the state’s largest industry lobbying group, supported the purchase, which they said would create jobs and keep costs down.
The mayor released a “climate forward” agenda Wednesday that outlines efforts to reduce greenhouse gas emissions from city operations as well as buildings and transportation.
About a dozen people opposed the acquisition of one or more of the sites based on concerns about loss of farmland, environmental impacts and potential loss of property values.
The Citizens Utility Board supported the proposal but sought to cap ratepayer costs.
Ratepayers will pick up the tab for $585 million of the $925 million cost — the estimated fair market value minus contributions from investors seeking to leverage federal tax credits — along with a 10% profit for Alliant shareholders.
The authorization requires Alliant to conduct noise studies and test for stray voltage at farms near the three large solar farms, though the commission did not require the company to conduct a study of the “heat island” effect, a condition suggested by PSC staff and some members of the public.
The commission also voted unanimously against drafting uniform setback requirements, instead encouraging developers to work with local communities and neighboring landowners.
“It actually sounds like a rule-making to me,” Nowak said. “If that’s what we need to start doing as a state, that directive needs to come from policymakers at the Legislature.”
Questions of cost, reliability
Alliant plans to retire its two remaining coal plants by 2025 as it seeks to cut its carbon emissions in half by 2030.
The company has told regulators that replacing coal plants — including the 1,100-megawatt Columbia Energy Center near Portage — with up to 1,000 megawatts of solar capacity can avoid up to $6.5 billion in additional costs over the next 35 years.
However, the Citizens Utility Board points out those savings will not necessarily mean lower bills for customers and that there are still unresolved questions about who will pick up the tab for coal plants that are retired before they are fully paid off.
“Alliant’s move toward cleaner energy sources is supported by the modeling it conducted as part of a collaborative energy planning dialogue,” said Citizens Utility Board executive director Tom Content. “Achieving savings for customers on costs for unneeded power plants is essential to achieve a sustainable energy future that everyone can afford.”
Commissioners, who in the past two years have approved almost 1,100 megawatts of utility-scale solar projects, acknowledged the significance of the shift while also voicing reservations about reliability and affordability as utilities transition away from fossil fuels.
The ruling, issued Wednesday, reverses a lower court’s 2019 order that struck down regulatory approval for the Nemadji Trail Energy Center, a controversial 625-megawatt fossil fuel plant.
Nowak questioned why Alliant has not included battery storage as it seeks to replace 1,000 megawatts of dispatchable power and noted that the company’s economic modeling included natural gas-fired generation in every scenario.
“There is such societal, economic and political pressure to move faster right now,” Nowak said. “This is a situation where I think it’s better to be a little more deliberate.”
Valcq agreed there are unanswered questions.
“I’m comfortable getting to 75 or 80%,” Valcq said. “It’s that last increment. I don’t know that there’s an answer.”
Commissioner Tyler Huebner applauded Alliant for including more than 100 megawatts of small-scale “distributed” solar and up to 50 megawatts of demand reduction in its plans.
While noting that Alliant did not model scenarios beyond 2040, he acknowledged that there may not yet be cost-effective technologies to address that last 20%.
“I think we all recognize there’s going to be challenges,” Huebner said. “We’ve got to be open to how we solve those challenges.”