The Senate in a close vote this afternoon approved a measure requiring electric utilities to derive at least 10 percent of their electricity from renewable sources by 2020.

The measure -- New Mexico Democratic Sen. Jeff Bingaman's renewable portfolio standard amendment -- was added to the Senate energy bill on a 52-48 vote.

The amendment requires utilities to use such renewable sources as wind, solar and geothermal power or biomass fuels made from wood or trash to generate at lest 10 percent of their power. Companies that cannot meet the standard would have to buy credits from utilities with excess renewable capacity.

The standards are popular in the states -- 19 now require utilities to meet similar goals. But many Capitol Hill lawmakers oppose national standards for utilities.

So while the vote was a significant victory for Democrats who are trying to put their imprint on this year's energy legislation, the amendment is not likely to make it through the anticipated House-Senate energy bill conference. Conference Chairman Joe Barton (R-Texas), who also is chairman of the House Energy and Commerce Committee, has said lawmakers in that chamber would not approve a national RPS.

Meanwhile, the Senate today rejected an energy bill amendment that would have mandated oil savings of 40 percent by 2025.

The oil savings proposal, offered by Washington Democratic Sen. Maria Cantwell, failed on a 47-53 vote.

Cantwell's amendment was derided by opponents as a "back-door" automobile fuel efficiency program that would force an unrealistic 185 percent increase in auto fuel efficiency standards.

Her proposal would have required the president to take action to reduce U.S. oil consumption by 7.64 million barrels per day by 2025. That would mean the nation would be using a total of 20.29 million barrels a day in 20 years -- slightly less than its consumption in 2004.

Assuming the oil savings were achieved by reducing the demand for foreign oil, imports would total 11.47 million barrels per day, a 40 percent reduction that is slightly less than what the United States imported in 2004 and about 1.58 million barrels a day less than what the country has imported so far this year.