A coalition of seven utilities in the Southwest is currently exploring the possibility of constructing a 250-megawatt solar power plant in Arizona or Nevada. If built, the plant could produce enough energy to power 160,000 to 200,000 homes. The proposed facility would likely utilize solar trough technology rather than more expensive photovoltaics. The group of utilities which includes: Arizona Public Service, Salt River Project, and Tuscon Electric Power is working to develop a request for proposals and hopes to seek approval for the project by early next year. In an effort to spur investments in renewable energy projects of this scope, the Arizona Corporation Commission passed a law that requires Arizona utilities to obtain 15 percent of their electricity from renewable sources by the year 2025.