An asteroid or a supervolcano could certainly destroy us, but we also face risks the dinosaurs never saw: An engineered virus, nuclear war, inadvertent creation of a micro black hole, or some as-yet-unknown technology could spell the end of us.

It's obviously tricky to convert cellulose to a useful biofuel. I think actually the most efficient way to use cellulose is to burn it in a co-generation power plant. That will yield the most energy and that is something you can do today.

Biofuels such as ethanol require enormous amounts of cropland and end up displacing either food crops or natural wilderness, neither of which is good.

Elon Musk Quotes