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The Path to a Sustainable Future

Nobel Laureate Steven Chu Addresses the World’s Energy Crisis in First Annual Jack Munushian Lecture

April 16, 2007 — Maximizing energy efficiency and developing a variety of clean alternative energy sources — such as solar cells, wind turbines and biofuels — must become a global priority if there is any hope of capping carbon dioxide emissions in the next 50 years, says Nobel Laureate Steven Chu, director of the Lawrence Berkeley National Laboratory.

Left to right: Dean Yannis Yortsos, Steven Chu, director of the Lawrence Berkeley National Lab, and EE Department Chair Daniel Dapkus.

Chu, a physicist whose distinguished career in academic research earned him a Nobel Prize in 1997, presented his views on the growing worldwide energy crisis to a standing-room-only crowd at the Viterbi School’s first Jack Munushian Keynote Lecture, hosted April 10, 2007 by the Ming Hsieh Department of Electrical Engineering.

At the present rate of growth, CO2 emissions are expected to double by the year 2056, Chu noted in his talk, titled “The World’s Energy Problem and What We Can Do About It.”  Current CO2 levels have reached about 400 parts per million (ppm) — higher than at any other time in history— but if they are unchecked, those levels will surpass 560 ppm in the next 50 years. 

Atmospheric scientists use that benchmark (550 ppm) to separate troubling from truly dangerous, planet-altering levels of atmospheric CO2.  They predict that if nothing is done to cap CO2 emissions now, levels will reach roughly 14 billion tons of carbon dioxide by 2056.

“What has me concerned is that the Earth’s climate is changing…we can say that with 90-to-99 percent certainty,” Chu said.  “This isn’t like the energy crisis of the ‘70s because we have that other looming issue, global warming, which is changing the equation.”

The signs of global warming are everywhere.  Increased temperatures are causing increased damage from storms, floods and wildfires.  Sea levels are rising faster than scientists thought.  Glaciers are disappearing.  There is increased species extinction and spread of diseases, such as malaria, Chu said.  And the world is experiencing more and more water shortages.

Keynote speaker Dr. Steven Chu.

Fossil fuels are primarily to blame, with oil contributing 43 percent of the total carbon emissions in 2002, coal contributing 37 percent, and natural gas claiming the rest.  But alternative energy sources cannot replace more than a fraction of the energy that is currently derived from fossil fuels, so would renewable sources be enough to support 6.7 billion people? Chu thinks so, if people are careful with energy now and if renewable technologies are fully supported.    

“Our world population is expected to peak at about 10 billion, then drop. We don’t know why, and I have my own personal theory, which is late night TV,” he laughed. “But if this is the case, we have a shot at getting a sustainable level of CO2 emissions and keeping it at, say, below 500 ppm.”

The U.S. will have to drop by a lot — it produces nearly 25 percent of the world’s carbon dioxide emissions today — and some smaller countries will be able to stay the same, he explained, but the real question is whether China, India and other developing countries will follow the United States’ example. 

Chu, who co-chairs an InterAcademy Council study, “Transitioning to Sustainable Energy,” is helping develop a roadmap for how countries around the world in different situations can transition to sustainable, clean energy.  His co-chair, Jose Goldemberg of Brazil, is a proponent of green fuels, such as ethanol and sugar cane, which currently account for nearly 40 percent of the transportation fuels in Brazil at costs that are considerably lower than gasoline.

“Transitioning is important, but conserving energy is even more important,” Chu said.  “I cannot stress how important it is to use energy wisely. That doesn’t mean people have to wear sweaters and sleep in sleeping bags.  It means don’t waste it.”  

Chu’s home institution — Lawrence Berkeley National Laboratory (LBNL) — has played a major role in the energy conservation movement in California and the U.S.  Among its many programs, LBNL conducts R&D in new energy systems and environmental

The Wind Farm, Palm Springs, CA.
solutions. Since the 1970s, promising new technologies have led to more efficient lighting, heating and appliances, which have made a dent in the state’s electricity demands and, consequently, helped to reduce California’s reliance on coal.

“We’ve transitioned away from natural gases, we use better building materials and insulation to cut heating costs, wind is actually a miracle of modern technology and growing in use, photovoltaics are better, and we have a lot of biomass (plant debris) that can be used for biofuels,” he said.

Chu, who is a professor of physics and of molecular and cell biology, is also a believer in the promise of biotech and genomic sequencing to help scientists genetically engineer new green fuels from microbes. He discussed a proposal at LBNL to genetically modify plants and algaes in order to make them self-fertilizing and resistant to droughts. These crops would be high in cellulose, which could then be converted to fuels by “designer bugs.”  He cited one of those projects, which focuses on termites. Scientists are studying the bacteria found inside of termites, with the hope eventually of mimicking that biological process to break down and convert biomass to energy.  

“If you look at the guts of a termite, there are bacteria that break down the cellulose and convert it to energy,” he said.  “We are sequencing the genomes of the microbes with the guts of termites … to understand what bacteria are present in termites that make them so efficient at converting biomass.”

The Jack Munushian Lecture was established to honor the late Jack Munushian, a professor emeritus of electrical engineering, who spearheaded the Viterbi School’s distance learning program.  Munushian, who died in 2005, organized the school’s computer science department and served as its first chair.