Nobel Prize-winning physicist Steven Chu is leading the Lawrence Berkeley National Laboratory's efforts to develop cleaner forms of energy, including new types of solar cells and new biofuels. He answered viewer questions about his research and the future of alternative fuels.
Wendy Smith, of the WWF Southeast Rivers and Streams Program, asks:
Because of my work on aquatic biodiversity and water issues I have concerns about biofuels. What is the ratio of water use to usable biofuels? How are scientists factoring in aquatic and terrestrial habitat needs into their research on biofuels?
Steven Chu responds:
Fresh water supplies will be one of the primary limitations to biofuel production. That is why the development of better plants such as hardy grasses which require far less water than corn or sugar cane is essential. Biodiversity is also important, and much easier to achieve for energy plants than for food plants. Ideally, we would like to plant a mixture of grasses.