We make the future sustainable when we invest in the poor, not when we insist on their suffering.

Now, we put out a lot of carbon dioxide every year, over 26 billion tons. For each American, it's about 20 tons. For people in poor countries, it's less than one ton. It's an average of about five tons for everyone on the planet. And, somehow, we have to make changes that will bring that down to zero.

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.

You're never going to get the amount of CO2 emitted to go down unless you deal with the one magic metric, which is CO2 per kilowatt-hour.

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.

By the time we see that climate change is really bad, your ability to fix it is extremely limited... The carbon gets up there, but the heating effect is delayed. And then the effect of that heat on the species and ecosystem is delayed. That means that even when you turn virtuous, things are actually going to get worse for quite a while.