A group of Southwestern utilities is exploring the possibility of developing a 250-megawatt solar power plant in Arizona or southern Nevada, which would be one of the largest in the region.
The feasibility of such a plant, which could produce enough electricity to serve 160,000 to 200,000 homes, is being studied by a consortium of seven utilities, including Arizona Public Service, Salt River Project and Tucson Electric Power.
Barbara Lockwood, manager of renewable energy for APS, who provided details of the project to the Arizona Corporation Commission on Thursday, said the group is serious about pursuing the plant, which would far eclipse in size previous solar projects built in Arizona.
By comparison, the most recent APS solar plant, the Saguaro Solar Trough Generating Station at Red Rock in Pinal County, produces 1.3 megawatts. Another major solar plant under construction in Boulder City, Nev., will produce 64 megawatts. In California, solar projects of 500 megawatts and larger are under development.
Lockwood said the consortium has hired a consultant to study possible sites for the plant. Finding the right site will be critical in determining if the project is feasible for all of the partners, she said.
Also the group is drawing up a request for proposals to present to solar power plant developers, who would build and operate the plant and sell the power to the utilities under long-term power-purchase agreements. If the project proceeds on schedule, the utilities could seek commission approval of those contracts by early next year, Lockwood said.
The ACC has been pushing Arizona utilities to invest in solar and other renewable energies to reduce the state’s dependence on fossil fuels, especially high-priced natural gas, for electricity production. Last year the commission approved a requirement that Arizona utilities obtain 15 percent of their electricity from renewable sources by 2025.
Solar electricity is more expensive than power generated by conventional methods, but the gap is expected to narrow as larger solar plants are built, because of the advantages of scale.
Commissioner Kris Mayes said power from a 250-megawatt solar plant still is not likely to be as cheap as electricity produced with natural gas, but she added “we know we have to get off our addiction to fossil fuels. Down the road it (solar power) will be competitive.”
Lockwood said the utilities have other problems to work out before the solar plant could be built including business and legal issues. Also she said the utilities are study a range of solar technologies that could be employed. Mayes urged the utilities to find a site in Arizona rather than building in Nevada. “It’s hard to swallow the notion of putting these plants in other states,” she said.
Kate Maracas, a member of the Western Governor’s Association Solar Task Force, said more incentives will be needed to close the gap in price between solar and conventional energy. She said the state could further promote the solar industry by streamlining solar plant construction permits, creating renewable energy enterprise zones and strengthening the longterm certainty that existing tax credits will continue.