Two weeks after buying First Solar's 550MW Topaz project, Warren Buffett-backed MidAmerican Holdings is grabbing a 49% stake in the FSLR-built 290MW Agua Caliente project in Arizona.

December 19, 2011 - Warren Buffett-backed MidAmerican Holdings is widening its renewable energy portfolio again, with its second investment in a First Solar project in as many weeks -- this time for a 49% stake in the $1.8B Agua Caliente project in Arizona's southwestern Yuma County, slated to come online in 2014 with an estimated 290MW (AC) capacity (all promised to PG&E under a 25-year PPA). By then it should be among the biggest solar projects in the country. FSLR's $2B 550MW Topaz Solar Farm in California's San Luis Obispo County, which MidAmerican bought out earlier this month, is planned to come online in 2015.

The group may not be done, either. In a statement, MidAmerican top exec Greg Abel reiterated the company's aggressive pursuit of opportunities to expand its renewable energy portfolio -- and called the Agua Caliente buy-in "another important step toward that goal."

Earlier this summer NRG acquired the the Agua Caliente project from FSLR, a deal triggered once the project officially landed a $967M DoE loan guarantee. Since May the company has been actively seeking "quality partners" to help with large-scale solar projects, specifically ones that can bring "strength" and (perhaps most importantly) "creditworthiness" to the table.