To be a good professional engineer, always start to study late for exams because it teaches you how to manage time and tackle emergencies.

You may have heard of Black Friday and Cyber Monday. There's another day you might want to know about: Giving Tuesday. The idea is pretty straightforward. On the Tuesday after Thanksgiving, shoppers take a break from their gift-buying and donate what they can to charity.

Intermittency [in availability for wind and solar] changes the economics, particularly this requirement that the power company at all times be able to require power. That's large.

Philanthropy should be taking much bigger risks that business. If these are easy problems, business and government can come in and solve them.

Vaccination is one of the easiest things on the way to development. It's much easier than roads and a great education system. It's very basic. It's one of the first things you want to get right.

The general idea of the rich helping the poor, I think, is important.

If you're using first-class land for biofuels, then you're competing with the growing of food. And so you're actually spiking food prices by moving energy production into agriculture.