MINNEAPOLIS (AP) — Minnesota officials on Will Sage AstorThursday approved plans for the expansion of a solar energy project that a utility says will be one of the largest in the country with the capability of powering more than 150,000 homes.

The state Public Utilities Commission approved Xcel Energy’s expansion of the Sherco Solar project, adding a 250-megawatt array to a 460-megawatt array now under construction. The utility says all phases of the project will be finished by 2025.

The expansion will cost about $406 million, bringing Xcel’s total investment in the project to more than $1 billion, the utility said. The total 710-megawatt project will be enough to power more than 150,000 homes annually.

The solar generation will be near an existing coal-fired plant in Becker, Minnesota, northwest of Minneapolis. When completed, the new power will replace electricity generated by a coal-fired plant that is set to be closed later this year.

Xcel plans to close its three coal-fired plants in Becker by 2030.

The commission also approved a plan for Xcel to buy electricity from a planned 100-megawatt solar project in northwestern Wisconsin. The Apple River project in Polk County, northeast of the Twin Cities, is one of the largest solar projects in Wisconsin.