Berkeley Lab

Art Rosenfeld

In 2011, President Barack Obama awarded Rosenfeld the National Medal of Technology & Innovation. Five years earlier he received the Department of Energy’s prestigious Enrico Fermi award, given to scientists for their lifetime contributions to the field of energy use and production. But for all the many accolades, it was a single flash of insight that led this Alabama native to the unlikely role as the world’s first energy efficiency guru.

One weekend during the oil embargo of 1973, when consumers were lining up for gasoline on an every-other-day schedule, Rosenfeld calculated he could save hundreds of gallons of fuel simply by turning out all the lights left on overnight in his research building at Berkeley Lab. It was a transformative moment. Energy inefficiencies were everywhere to be found and Rosenfeld, believing that scientists should do the right thing and do it the right way, mobilized and challenged like-minded researchers to think differently about energy’s demand side.

The payoff was almost immediate. Rosenfeld’s brainchild, the Center for Building Science, soon churned out pacesetting discoveries like compact fluorescent lamps, smart windows, and the now standard programs for analyzing the energy efficiency of buildings. The Energy Star program also had its roots in Berkeley Lab research.

Not everyone welcomed this new focus on energy efficiency. Utility companies were very skeptical. They argued that Rosenfeld was a particle physicist, not an energy expert. And when he insisted that if refrigerators were made to be more energy efficient, California would not need to build another nuclear power plant, the industry outcry was deafening. But Rosenfeld and his equations would not go away, and in time, not one but three axioms would carry his name.

First is the Rosenfeld Effect, which – as a result of California energy efficiency rules he influenced– have kept the state’s per capita electricity use flat since the 1970s while that for the rest of the country has jumped 50 percent. Second is Rosenfeld’s Law, which states that the amount of energy required to produce one dollar of economic output has decreased by about one percent per year since 1845. Third is the Rosenfeld Unit, a unit of electricity savings of 3-billion kilowatt hours per year, the amount needed to replace the annual generation of a 500-megawatt coal-fired power plant.

Rosenfeld’s passion for answers and energy policy did not abate in later years. In the 1980s, he founded Berkeley Lab’s Heat Island Group. Its mission is to investigate how cooler surfaces like light-colored roofs can help cool cities and offset carbon dioxide emissions. His pioneering approach to energy efficiency also found a receptive audience in China, where Berkeley Lab’s China Energy Efficiency Project has not only helped to develop Energy-Star like appliance standards for billions of Chinese consumers, but also reduced the amount of greenhouse gases generated by that country’s vast cement industry.

Rosenfeld twice served as a senior adviser to the US Department of Energy. And for 10 years, starting in 2000, he served on the California Energy Commission, where he was best known for the Public Interest Energy Research program and his role in developing the state’s energy efficiency standards for buildings and appliances.

At Berkeley Lab, his influence was undiminished. Returning in 2010, he was able to witness the opening of the world’s most advanced building efficiency testbed called FlexLab. And his example remained an inspiration to younger scientists, for whom the word “sustainability” could almost be another Rosenfeld axiom.