Who knew David Letterman installed geothermal heat pumps under his house?

Letterman discussed his green retrofit with Stanford Woods Institute Senior Fellow Mark Z. Jacobson (Civil and Environmental Engineering), on the Oct. 9 episode of "Late Night With David Letterman." The two had a wide-ranging conversation centered on studies Jacobson has led showing the feasibility of converting global, national and state energy infrastructures to all-renewable sources. (Read more about Jacobson’s renewable energy blueprints.)

“There’s no technological or economic limitation to solving these problems,” Jacobson said. “It’s a social and political issue, primarily.”

Jacobson and his co-authors have published studies on how to switch to all solar, wind and water energy sources for the world, the U.S. and New York State. They will soon publish a study for California, and they have plans to do studies for all 50 U.S. states.

The plans show the way to a sustainable, inexpensive and reliable energy supply that could create local jobs and save billions of dollars in pollution-related health costs. They outline paths to fulfilling all transportation, electric power, industry and heating and cooling energy needs with renewable energy by 2050. To do this, they calculate the number of new devices and jobs created, land and ocean areas required, and policies needed for infrastructure changes.

Speaking with Letterman, Jacobson expressed confidence in America’s ability to rise to the occasion. “In World War II, the U.S. produced 330,000 aircraft within five years just because it was necessary.”

Jacobson is director of Stanford’s Atmosphere/Energy Program and a senior fellow with the Precourt Institute for Energy.

Stanford Woods Institute researchers are seeking ways to adapt to climate change and address its underlying causes. Learn more about Woods-sponsored climate research.