Sargas seeks instead to make the capture of carbon dioxide more efficient by cranking up the pressure. Its plants would burn gas or coal at high pressures, thus yielding a high-pressure exhaust in which the CO2 pressure is about 20 times higher than in a conventional coal plant. That pressure makes separating the CO2 from nitrogen and left-over oxygen in the exhaust far less costly.

Last week a consortium of companies in Norway including aluminum giant Alcan (a major power consumer) and Norwegian energy firm Norsk Hydro announced plans to build a 400-megawatt coal-fired power plant using Sargas' design; startup is targeted for 2011. Dale Simbeck, vice president of technology for Mountain View, CA-based energy consultancy SFA Pacific, calls it a "clever scheme" because coal is relatively cheap, while the high pressure system will help contain the cost of capturing the CO2. "What they're doing can make sense," says Simbeck.

Tor Christensen of Sargas says the company is working with a major United States-based oil and gas producer to exploit another feature of high-pressure combustion: the system's compact design. For a given power output Sargas' generators handle a volume of gas 40-50 times smaller than would a conventional plant. As a result the equipment is more compact—compact enough to put a 100-megawatt natural gas-fired plant on an offshore platform. "It's not much for an offshore platform," says Christensen of the 5,000 metric ton design. "A single crane can lift the whole thing."

McRae says the idea should be attractive for oil and gas producers. For one thing, Sargas' plants will capture CO2 on-site, eliminating the need to ship CO2 from shore. For another, they will serve the platform's power needs better than the diesel generators and relatively small gas turbines used today. "One of the big problems with offshore oil platforms is the power supply that you need to pump the oil and process the gas that comes out the ground. Sargas will allow you to get much larger power in a smaller space," says McRae.

Christensen says Sargas' goal is to deliver CO2 to oil platforms at roughly $20 per metric ton and, as a rule of thumb, each metric ton of CO2 should yield two or three extra barrels of oil. If oil prices stay high, says Christensen, "there's a tremendous amount of money to be made."