The Select Committee on Energy Independence and Global Warming hearing Wednesday also covered safety issues following the explosion last week at the Upper Big Branch mine in West Virginia that killed 29 miners.
The explosion requires a closer look at the "entire structure of mining safety," said committee Chairman U.S. Rep. Edward Markey, D-Mass., The Hill reports.
Coal giants represented at the hearing included Peabody Energy Corp. and Arch Coal Inc., and Rio Tinto PLC, the nation's biggest coal operators.
Officials from the fourth largest coal company, Massey Energy, operator of the Upper Big Branch mine, didn't attend.
Massey's outspoken chief executive, Don Blankenship, has referred to global warming as a "hoax" and a "Ponzi scheme," The Guardian reports.
Markey urged the executives to "cease efforts to deny the science of global warming" and stop "misleading the public as to the true science behind climate change."
But the coal executives testifying at the hearing distanced themselves somewhat from Blankenship's strong position by saying that climate change was a "serious" issue that needed to be addressed.
They maintained, however, that the House of Representatives-passed energy and climate bill would raise the costs of coal, adversely affecting the industry as well as the economy. The legislation is being negotiated further in the Senate.
Peabody Chief Executive Officer Gregory Boyce was critical of the climate bill, which would put a price on carbon emissions. Instead, he said, Congress should allow carbon-reducing technologies such as carbon capture and sequestration to develop before imposing strict emissions caps.
Boyce estimated CCS technology could be ready for commercial-scale use in the 2020s.
Ohio Coal Association President Michael Carey said the Obama administration had declared a "war on coal' through its regulatory efforts to reduce pollution.
Rep. Jay Inslee, D-Wash., retorted that the climate bill would give an estimated $60 billion in subsidies to the industry over the next two decades for the development and deployment of clean coal technology.
"We don't give $60 billion to people we are at war with. We aren't giving $60 billion to al-Qaida," Inslee said.
The hearing was briefly interrupted by protesters in surgical masks, who dropped chunks of coal in front of the coal executives.
"Coal is dirty," one of the protesters said.
According to the Energy Information Administration, U.S. coal consumption decreased by 10.7 percent -- 120.1 million tons -- to a level of 1 billion tons in 2009.