BOISE, Idaho (AP) — Idaho is going green whether it wants to or not. The Idaho Public Utilities Commission in the last several months has approved agreements for 13 solar projects.

A combination of federal regulations, tax incentives, cheaper solar panels and a rate-calculating method approved by the commission itself has made solar power economically attractive in Idaho. But commissioners and Idaho Power Co. officials say the projects could end up costing ratepayers more because utilities will face uncertainties by being forced by federal rules to integrate power from a source that fluctuates with the sun.

Solar power backers say solar power won't cost ratepayers more and will provide clean energy. Officials say the 13 projects spread across southern Idaho add up to about 400 megawatts. That's enough to power up to 400,000 homes.