Burning coal emits large amounts of greenhouse gases as it makes half of the U.S.'s electricity.

The Union of Concerned Scientists is calling on its membership to put pressure on William Clay Ford Jr., chairman of the Ford Motor Company, to make a public break with the U.S. Chamber of Commerce and “its stance of denying the science and need for action on climate change.”

The action from the pressure group comes as the Senate Environment and Public Works (EPW) Committee passed over the objections of Republican members the “Clean Energy Jobs and American Power Act” this morning, setting the stage for the rest of the Senate to move forward with controversial climate change legislation.

The bill sets a short-term target of reducing green house gas emissions 20% below 2005 levels by 2020. Critics contend that to do so will wreck the economy. The act also establishes a “cap-and-trade” system to reduce U.S. greenhouse gases.

At stake are billion of dollars in credits — or taxpayer giveaways — to power and oil companies in voluntary greenhouse gas emissions trading markets or in mandatory emissions trading markets, if they are legislated.

Like the already passed House bill, the Senate bill requires periodic scientific assessments to ensure the program is operating effectively. Unlike the House measure, the bill would retain the Environmental Protection Agency’s (EPA) authority to require emission reductions from the oldest and dirtiest powerplants.

The Chamber of Commerce, a lobbying organization with thousands of large and small business members across the nation, is actively working against what it says is “ill-conceived climate change policies and measures that could severely damage the security and economy of the United States.”

The Chamber is unhappy with EPA’s proposed greenhouse gas emission reporting standards, and has filed comments against the rules that are apparently a prelude to litigation.

“Ford’s clean car commitments are undermined by their (sic) continued participation in the Chamber—the very group now suing to stop the Environmental Protection Agency from moving forward on efforts toward cleaner cars and other global warming solutions,” according to UCS.

A number of large companies concerned about their environmental image, including Apple, Microsoft, and energy companies Exelon and PG&E, have publicly distanced themselves from the Chamber over its climate change stance.

The Chamber is actively involved in litigation against the Environmental Protection Agency on several matters. Most recently, it sued EPA over its decision allowing California to adopt and enforce its own automobile emissions standards. “The waiver opens the door to a dual set of costly emissions standards by California and other states,” according to the Chamber.