I'd put my money on the sun and solar energy. What a source of power! I hope we don't have to wait until oil and coal run out before we tackle that.

What most people know but don't realize they know is that the world is almost entirely solar-powered already. If the sun wasn't there, we'd be a frozen ice ball at three degrees Kelvin, and the sun powers the entire system of precipitation. The whole ecosystem is solar-powered.

I have had a lot of success with failure.

In energy, you have to plan and do research way in advance, sometimes decades in advance to get a new system that's safer, doesn't require us to go around the world to get all our oil.

Information, education, skills, healthcare, livelihood, financial inclusion, small and village enterprises, opportunities for women, conservation of natural resources, distributed clean energy - entirely new possibilities have emerged to change the development model.

The main thing that's missing in energy is an incentive to create things that are zero-CO2-emitting and that have the right scale and reliability characteristics.