President-elect Obama will name Steven Chu, a Nobel Prize winner and director of the Lawrence Berkeley National Laboratory, as Energy Secretary, according to several news reports.

Neither the transition nor the Berkeley lab would confirm or deny that Obama has asked Chu to become Energy Secretary. Lab spokesmen said Chu will be traveling in China and the U.K. until Sunday, so a formal announcement before Monday is unlikely.

The Berkeley lab, which is under the umbrella of the Energy Department, is considered one of the most prestigious scientific institutions in the world. Chu’s background is in atomic particle physics, which gives him the expertise to oversee Energy’s chief portfolio, managing the nations’ nuclear weapons and nuclear science programs.

However, in recent years, Chu has shifted his focus to the study of climate science and renewable and alternative energy research, which also positions him to lead the Department in implementing Obama’s sweeping and ambitious energy and climate change proposals, aimed at curbing CO2 emissions and transforming the U.S. fossil-fuel based economy. Since Chu became director of the Berkeley lab in 2004, he has initiated several new programs aimed at researching and developing alternative and renewable energy.

Obama is expected to announce the Energy Secretary in conjunction with a full energy and environment “team”, and sources close to the transition said not all those picks have yet been nailed down.

Carol M. Browner, who was administrator of the Environmental Protection Agency in the Clinton administrator, is expected to take on a newly created role heading a White House energy and climate council, which would coordinate energy and climate policy efforts across the cabinet.

On Wednesday, aides said Nancy Sutley, an energy and environment aide to the mayor of Los Angeles, is likely to be named head of the existing White House Council on Environmental Quality, which currently coordinates environment and climate change policy for the administration.

Lisa Jackson, former head of New Jersey’s Department of Environmental Protection, is expected to be named as E.P.A. head. However, sources close to the transition said they have not yet settled on a nominee to head the Interior Department.

Last week, California Rep. Mike Thompson , D, and Arizona Rep. Raul M. Grijalva were considered top contenders, but sources close the transition say that “problems and concerns” have arisen with both candidates. New names emerging this week to fill the Interior slot include two former assistant secretaries of the Interior in the Clinton administration: Kevin Gover, now director of the Smithsonian’s National Museum of the American Indian, and John Berry, now director of the National Zoo.