Published Jan 1, 2007 8:00 AM

24. Surge Protector

What: Energy-saving appliances

Who: Particle physicist Art Rosenfeld

Impact: The foundations for the energy-saving revolution began in the '70s, but it was in the next decade that Lawrence Berkeley National Laboratory (LBNL) particle physicist Art Rosenfeld laid out the intellectual underpinnings of the new field — which gave rise to fluorescent light bulbs, energy-saving air refrigerators, and the like — at the Center for Building Science, which he founded at LBNL. When Rosenfeld received the Fermi Prize for lifetime achievement in physics in 2006, the EPA credited all the efficiency initiatives adopted between 1973 and 2005 with saving an annual amount of electricity equivalent to 21 percent of U.S. consumption, or $228 billion dollars.

Eureka moment: November 1973: Gas supplies have been cut by the month-old Arab Oil Embargo and people wait in long lines to buy gas. Rosenfeld's office is lit by 12 dazzling 60-watt light bulbs, which makes it easy for him to see a startling calculation. The light bulbs in his office are burning the equivalent of a .5 gallon of oil per hour, and if he leaves them on all weekend, as nearly everyone does, his empty office will have burned the equivalent of three gallons of gasoline by the time he returns on Monday morning. "There are 20 lights in the hallway between my office and the door of the building," he recalls, "and I figure it'll save several cars' worth of oil if I turn them off."

— Lisa Margonelli