Obama announced the nomination of the Nobel-Prize winner at a press conference in his transition office headquarters in Chicago, Illinois, as he presented his energy and environment team members to the nation.

"They are leading experts and accomplished managers," Obama said of his team. "They are ready to reform government and help transform our economy so that our people are more prosperous, our nation is more secure, and our planet is protected."

Chu, currently head of the Lawrence Berkeley National Lab in California, was described by Obama as the one "who has been working at the cutting edge of our nation's efforts to develop new and cleaner forms of energy."

"Steven is uniquely suited to be our next secretary of energy as we make this pursuit a guiding purpose of the Department of Energy, as well as a national mission," he said of the energy secretary choice.

Obama also noted Chu's appointment sent a signal to all that the US government would value science and make decision based on the facts.

Chu, born on February 28, 1948, to a Chinese American family in Missouri, won his Nobel in 1997 with two other scientists for developing methods to cool and trap atoms with laser light.

Since 2004, he has been running the Lawrence Berkeley National Laboratory in California, which is attached to the energy department, and has a budget of 645 million dollars and a staff of 4,000.

If his nomination is approved by the Senate, Chu is expected to lead Obama's agenda to create 2.5 million new jobs through "green" and new technologies, and reduce the country's dependence on foreign oil supply.

"I look forward to being part of President-elect Obama's team which believes we must repair the economy and put us on a path forward towards sustainable energy," Chu said at the press conference.

He defined the role of the Department of Energy as "a major force in meeting the challenges" by supporting "energy research and development" that will lead to innovation in the private sector, to nurture broad-based scientific research that is essential for the country's future prosperity, and to provide scientific leadership to minimize the proliferation and use of nuclear weapons.

Other key posts Obama announced to fill include Carol Browner as the newly-created "climate czar" at the White House, Nancy Sutley as chairwoman of the White House Council on Environmental Quality, and Lisa Jackson as head of the Environmental Protection Agency.

He said that nominees for the secretaries of the interior, transportation and agriculture, who he said also play important roles in energy and environment policies, would be announced in the days to come.