Reuters: Solar thermal power developer Ausra Inc on Thursday opened a 5-megawatt demonstration plant in California that it says will prove it can deliver on its promise of providing clean energy cheaply. Ausra, the first to erect a solar thermal plant in California in nearly 20 years, is among a handful of so-called concentrating solar power (CSP) developers that say they will deliver utility-sized solar plants in the next three to five years that will be able to sell power at prices …