Chu, a Chinese-American who currently is director of the Lawrence Berkeley National Laboratory in California, has in recent years campaigned to bring together a cross-section of scientific disciplines to find ways to counter climate change.
If action is not taken now to stop global warming, it may be too late, he argues.
Since 2004, Chu has been director of the Berkeley lab, the oldest of the Energy Department's national laboratories, with its 4,000 employees and a budget of $650 million. The laboratory does only unclassified work and under Chu has been a center of research into biofuels and solar energy technologies. He is a former head of the physics department at Stanford University.
Chu, 60, brings additional diversity to the Obama cabinet.
Born to Chinese parents in St. Louis, he grew up in the Queens borough of New York City. His father, a Massachusetts Institute of Technology graduate and professor of chemical engineering, and mother came to the United States in 1943 and two years later decided to stay because of the political turmoil in China.
One of the country's most renowned scientists, Chu in 1997 shared the Nobel Prize in physics with two other scientists for his research into ways to cool and trap atoms using laser light. By cooling atoms to minus-273 degrees Celsius, they found the movement of atoms can be slowed to a point where they could be trapped and manipulated.
More recently, Chu's scientific interests have centered on energy and finding ways to replace fossil fuels with other energy sources such as biofuels from plants and converting energy from the sun into a fuel. He has spoken frequently about the need to link the physical and biological sciences with engineering to rally independent-thinking scientists in the fight against climate change.
"Steve Chu is a world-class intellectual," said Stanford University environmental scientist Steve Schneider, who knows Chu. "When I heard that name (for energy secretary), I smiled." Schneider said Chu will push hard within the Obama administration for reductions in the greenhouse gas emissions blamed for global warming.
Obama has promised to move quickly on energy issues, including a push for more alternative fuels and to get Congress to address climate change.
Chu frequently has used the bully pulpit in a campaign against global warming and the need for alternative energy and greater energy efficiency. During a lecture last summer in Washington he bemoaned the fact that people too often prefer to spend $1,000 on a granite kitchen counter top instead of improving their home's energy efficiency.
A few years ago he was one of six Nobel Prize-winning scientists who expressed their concern about global warming by sitting against and climbing into a massive tree on the campus of the University of California at Berkeley for a photograph that appeared in a special environmental issue of Vanity Fair magazine.
Despite his broad scientific credentials, Chu has little experience inside Washington or in what occupies much of the Energy Department's business - maintaining the nation's stockpile of nuclear weapons and weapons research. Nor has he had much involvement in nuclear energy. He has shown little support for building a nuclear waste repository at Yucca Mountain in Nevada, one of the major issues facing the department. Obama also has expressed dislike for the Yucca project.
Chu as energy secretary would head a department with a $25 billion budget and 14,000 employees and more than 193,000 contract workers. Two-thirds of its budget involves activities related to nuclear weapons research and maintenance.
Ironically, the department Chu would lead also has been a target of Chinese-American activists who in the late 1990s became incensed over its pursuit of Wen Ho Lee, a Chinese-American computer engineer, over allegations of spying at the Los Alamos National Laboratory in New Mexico.
Lee was fired and prosecuted for security violations, but has never been charged or linked to spying activities. Eventually a federal judge apologized for the way Lee was treated.
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