What does a sustainable energy future look like?

What does a sustainable energy future look like? Jack Brouwer of University of California, Irvine, answers the question on this edition of "Ask a Scientist."

The number of humans alive on our planet today is 7.6 billion. By 2087, projections show that 11 billion people will live on Earth. How will we continue to have a sustainable supply of food, energy and water? National Science Foundation-supported scientists are searching for answers.