We don't need a fuel that's cleaner, we need a fuel that happens to be cleaner, but is half the price of oil.

If everyone played it safe, we wouldn't get anywhere.

In my view, it’s irreverence, foolish confidence and naivety combined with persistence, open mindedness and a continual ability to learn that created Facebook, Google, Yahoo, eBay, Microsoft, Apple, Juniper, AOL, Sun Microsystems and others.

Setting an aggressive enough carbon-reduction goal will result in an appropriate price for carbon and will help many a renewable technology. Consumer education will help. Most importantly, though, will be the continually declining cost trajectory of the real breakthrough in clean-technology costs driven by research and innovation. In the end, private capital is the real barometer of change.

Startups allow technologists and scientists to take risks and change plans in a way that would be frowned upon in a big company. Having said that, big companies will play a key role in certain areas and in partnerships with little companies. Each has its strengths.

The willingness to fail gives us the freedom to succeed.

Now it will take a long time to scale biofuels, but I'm the only one in the world forecasting oil dropping in price to $35 a barrel by 2030. I'll put it on the record: Oil will not be able to compete with cellulosic biofuels. If you do it from food, the food will get so expensive you can't make fuel out of it.