Back when Italy was trying out nuclear power for the first time, Cesare Silvi was one of the guys who had to figure out how to make it safe. Sometimes crazy things would happen — once, an oil pipe burst, fouling the cooling water intake of a nuclear power plant miles away, shutting it down. Soon Silvi discovered there were many other pipes even closer to that plant; his attempt to study them was stymied by the moneyed interests who own them.

The longer he looked, the more small, improbable, but potentially disastrous scenarios piled up — war, terrorism, plane crashes, missiles, extreme weather — leading him to eventually conclude that if you armored a nuclear power plant against all potential disasters, you could never produce power for a reasonable amount of money.

So twenty years ago he switched to solar, and is now the president of the International Solar Energy Society. Here's what he has to say about nuclear power today.

“Human history is full of madness, full of catastrophes. Imagine if we had nuclear reactors when we fought wars in the past. If you try to consider all the events that might happen over the years, you start to ask, ‘What are the benefits of such an effort, especially when you have opportunities to get electricity in many other ways?’”