You have to be willing to spend an awful lot in that R&D phase before you see the benefits. When you look at the companies that have really won customers over in technology - say, Apple and Google - you find that they spend billions of dollars on R&D each year, often spending that much on a product before they ever make a dime back in profits.

If your incentives are set up wrong - if for some reason you reward people for behavior that's actually bad for your customers or your organization - then you're going to encourage that behavior.

Unfortunately, in the environment, I don't see as much willingness to invest heavily in R&D as I do in consumer technology. And that's a pity.

I was much more of a naïve techno-optimist than I am now. I still believe that technology can help us come out of this situation with a richer humanity with less impact on the planet, but now I think it has to be paired with effective policy in order to achieve that.

I think the environmental movement is now so large and diverse that it's hard to talk of it as a single entity.

Often we need to use policy to level the playing field, or to be sure that a technology is managed in a responsible way.

If you want to feed the planet and keep the forests we have, you need to be able to grow roughly twice as much food per acre around the world. How do you do that? New technology.