Arthur Rosenfeld, nicknamed the “godfather of energy efficiency,” spent half his life as one of energy efficiency’s most tireless advocates. He began his career as a student of the Nobel-prize winning physicist Enrico Fermi and dedicated decades as a professor of physics. Energy efficiency captured his attention during the oil crisis of 1973 when he noticed how Americans’ wasteful consumption of energy worsened high fuel prices and long lines at gas stations. One weekend, after turning off all of the office lights left on by departed colleagues, he calculated the costs of the wasted electricity and committed himself to creating a more efficient country. For the next forty-three years, he campaigned for more efficient technologies. He established the Center for Building Science at the Lawrence Berkeley National Laboratory in California, pioneered research into better lighting and home building technologies, and served both the federal government and the state of California. His influence on California policymakers helped the state earn honors as the country’s most-efficient state for nearly four decades. Art Rosenfeld’s accomplishments and influence are both impossible to measure and impossible to miss.

Since his passing, Rosenfeld’s impact is noticeable in the many heartfelt thoughts shared by both colleagues and admirers. California Governor Jerry Brown, who worked closely Rosenfeld since the 1970s, shared his thoughts in a statement. “Art Rosenfeld helped make California the world leader in energy efficiency,” remarking that “his pathbreaking ideas transformed our energy sector from one of massive waste to increasingly elegant efficiency.”

For us at Lime Energy, Rosenfeld paved the way for our work. “Art Rosenfeld was an inspiration to generations who have worked to improve the efficient use of energy,” recalled Lime Energy’s President and CEO Adam Procell, “he leaves us a legacy of results that will have enduring environmental and economic benefit. He was a great example of how one person can make a difference, how an intelligent approach to problem solving can rally meaningful action and how important education is to making critical gains as a society. We are saddened by his passing, but we hope that it will serve as a call to re-double our efforts to capture the remaining energy productivity gains that are critical to the United States and the world.”

Arthur Rosenfeld was a true icon of the energy efficiency community. Everyone at Lime Energy, either directly or indirectly, shares gratitude for his contributions. Rosenfeld was 90.