Oct. 31--NEW HAVEN, W.Va. -- Coal-filled barges navigate the Ohio River to deliver the black rock fossil fuel to the sprawling Mountaineer power plant.

Coal-fired power plants such as Mountaineer release huge volumes of carbon dioxide into the atmosphere. As a greenhouse gas, CO2 is considered by many scientists to be a major contributor to climate change.

In some circles, nationally and internationally, coal is now considered a villainous rock -- associated with mountaintop removal strip mining, pollution and a warming planet.

But coal was king Friday in West Virginia at the Mountaineer plant, an Appalachian Power Co. generation facility. For invited guests, Ohio-based American Electric Power, parent company of Appalachian, formally commissioned a demonstration project employing a new technology for capturing and storing CO2 extracted from flue gases produced by the coal-burning plant.

Mike Morris, AEP's chairman, president and CEO, described Friday as a historic day. West Virginia Gov. Joe Manchin said the carbon capture and storage system will allow coal to continue to play a key role in power generation until transition occurs to the "fuel of the future."

Philippe Joubert, president of Alstom Power, the international company that designed the chilled ammonia carbon capture and storage system, went further. He said the new technology will "change the power generation market and change the world."

Officials said the Mountaineer project is the first process worldwide to combine carbon capture with storage of carbon dioxide. The carbon dioxide removed from the flue gases is injected under pressure through two wells into deep geologic formations, believed compatible with storage, thousands of feet below Mountaineer.

But the technology is unproven, and many questions linger about its safety, effectiveness, long-term effects and financial viability.

For example, how much carbon dioxide can the underground formations accommodate? How far will the plume spread? What disaster might an earthquake render?

Carbon capture will be expensive, and kilowatt hour production costs of electricity are likely to double -- a reality consumers will discover in their electric bills.

And critics note that Mountaineer will still rely on a fuel harvested through practices that include mountaintop removal and other strip-mining techniques that disturb vasts swaths of ground and can affect ground and surface waters.