The Department of Energy announced Thursday that it has awarded First Solar, America's dominant solar manufacturer, nearly $4.5 billion in conditional loan guarantees to support the construction of three solar power plants in Southern California. With the latest awards, First Solar, headquartered in Tempe, Ariz., has nabbed a third of the $16 billion in loan guarantees the DOE has granted for solar generation to date. In January, First Solar was awarded a nearly $1 billion loan for its 290-megawatt Agua Caliente project in Arizona. First Solar expects the three projects, which should begin delivering electricity in 2014, to create 1,400...