Add Google's reluctant voice to the growing chorus of observers who doubt that a U.S. carbon cap-and-trade law can be passed this year.

Dan Reicher, Google's director of climate change and energy initiatives, said Tuesday that the American Clean Energy and Security Act may well "be caught in gridlock" in the U.S. Senate.

The bill passed the House of Representatives in June, and Senate Democrats are expected to unveil a very similar bill in the Senate as early as tomorrow, Reuters reported.

But "The likelihood of progress in the Senate is dimming," Reicher said in a speech at the REFF-WEST conference in San Francisco.

Reicher isn't happy about that. But his comments reflect a growing consensus that backers of the bill – which seeks to cut the nation's greenhouse-gas emissions by 17 percent by 2020 and by about 80 percent by 2050 through a cap-and-trade program – are going to have a hard time bringing it to a vote this year (see Green Light post).

Not only has the cap-and-trade provision brought down the ire of such industry groups as the U.S. Chamber of Commerce and the American Petroleum Institute, but the Senate also faces a lot of other challenging tasks, such as dealing with proposed health insurance reform (see Energy-Climate Bill Could Boost Electricity Costs 20% by 2030).

The Obama Administration has said it wants a cap-and-trade law to bring to the December meeting in Copenhagen to craft an international agreement to replace the Kyoto Protocol (see White House Planning Climate Strategy for Third Week of September).

The difficulty in getting a national climate bill passed could be a precursor to an even tougher battle over the United States joining in any such new treaty, given that that would require a two-thirds vote in the Senate, Reicher noted.