Milwaukee Journal Sentinel:

Signaling the early stages of a historic transition, WEC Energy Group, the parent company of We Energies and Wisconsin Public Service, last month announced its first large investment in solar power.

Once the darlings only of the green-energy crowd, solar and wind projects now have become the least expensive way for utilities to add new power generation. As a result, they’re changing how utilities plan to operate in the coming decade.

“The technology keeps getting better and better —and, the most important thing, cheaper,” said Gary Radloff, who retired this year as director of energy policy analysis for the Midwest at the Wisconsin Energy Institute, a research center at the University of Wisconsin-Madison.

Wisconsin Public Service, the subsidiary of WEC Energy Group that operates in northeastern Wisconsin, and Madison Gas and Electric plan to invest a total of $390 million to buy 300 megawatts of generating capacity — enough electricity for more than 70,000 residential customers — in two solar power projects. We Energies is expected eventually to buy the remaining 150 megawatts in one of the two projects.

The investments are part of WEC’s long-term plan for electricity from the sun, wind and natural gas to make up a larger share of its generating capacity in the next decade. Natural gas, now in abundant supply, will be an important part of that mix: Natural gas power plants can be built for a fraction of the cost of coal-fired plants and are less costly to operate and maintain.

But solar power, which is better suited overall for Wisconsin than wind power owing to weather patterns and other factors, is certain to make up a growing share of the state’s power generation in the coming decades. The cost is roughly half of what it was four years ago, said Dan Krueger, senior vice president of wholesale energy and fuels for WEC Energy.

More: WEC Energy bets on solar, wind and natural gas. So, what about coal?