energy talk by Bill Gates

A collection of interesting/inspiring speeches on TED always amaze me, but this Bill Gates on energy, I couldn't help but wonder if people really believed in our technology to save us from predicted disastrous future. Yes, it is the technologies, or the human intelligence I should call it here, that improved and advanced our life. Generally people live longer, safer and healthier than what it was hundreds of years ago where technology level was much lower. However, at the same time, this technology has created other issues we did not have hundreds of years ago - climate change, chronic diseases such as asthma, acid rain, water contamination and et cetra. We know that our intelligence can never be enough to predict the future with hundred percent certainty. By now, we know that there is always a downside for an amazingly beneficial innovation such as the nuclear technology. And still, we think that our future, and the future of this magnificent planet can be secured by our intelligence - Really?