Business Mirror: Bill Gates and Exxon Mobil are among those who see huge potential–and challenges–in wringing fuel from algae. Inside an industrial warehouse in South San Francisco, California, Harrison Dillon, chief technology officer of startup Solazyme Inc., examines a beaker filled with a brown paste made of sugar cane waste. While the smell brings to mind molasses, this goo, called bagasse, won’t find its way into people-pleasing confections. Instead, scientists will empty it into …