Even as clean energy enthusiasts assembled in Las Vegas, the bad news came that Solyndra, the US's flagship solar company, has filed for bankruptcy.  The California startup had received $527 million in federal stimulus investment plus a personal visit from President Obama.  In Oregon Secretary of Energy Steven Chu put his head together with Intel CEO Paul Otellini to figure out how to interest more American students in engineering.  Meanwhile, Al Gore proclaimed Tar sands "the dirtiest fuel on the planet."