Long Beach, California (CNN) -- Microsoft Corp. founder and philanthropist Bill Gates on Friday called on the world's tech community to find a way to turn spent nuclear fuel into cheap, clean energy.
"What we're going to have to do at a global scale is create a new system," Gates said in a speech at the TED Conference in Long Beach, California. "So we need energy miracles."
Gates called climate change the world's most vexing problem, and added that finding a cheap and clean energy source is more important than creating new vaccines and improving farming techniques, causes into which he has invested billion of dollars.