Texas billionaire T. Boone Pickens has always been one to think big. But his sweeping 10-year energy plan for America faces obstacles that may be insurmountable.

After years of optimistic predictions and false starts, it looks like solar's moment is here at last. Analysts say a pattern of rapid growth, technological breakthroughs, and falling production costs has put solar power on the brink of becoming the world's dominant electricity source.