WASHINGTON, July 21 (UPI) -- The United States may fall behind in carbon dioxide-storage technology, the vice president of Consol Energy Inc. (NYSE:CNX) warned.

"If the United States chooses not to make the necessary investments … then there's the potential that the U.S. will not be exporting the technology, but importing it," said executive Steven Winberg.

The company has invested about $500,000 in a prototype 275-megawatt coal power plant slated for Mattoon, Ill, that would separate the pollutant carbon dioxide and store it thousands of feet underground, the Pittsburgh Tribune-Review reported Monday.

The U.S. Department of Energy pulled away from the investment, when construction costs mushroomed from $1 billion to $1.8 billion, the report said.

The concept found support at the G-8 economic summit in Japan in June. G-8 leaders called for 20 large demonstration projects to be up and running by 2010.

Presumptive Republican presidential nominee Sen. John McCain, R-Ariz., has said he supports the concept, but noted cost is a "legitimate concern."

Presumptive Democratic presidential nominee Sen. Barack Obama, D-Ill., has thrown support specifically to the Mattoon project, signing a letter that charged the Department of Energy pulled away because Illinois was chosen for the project, rather than President George Bush's home state of Texas, the report said.