You've heard plenty about how a buildup of carbon dioxide in the air is promoting global warming, and how industry might be told to cut back its emissions.
But have you heard about stuffing the gas in the ocean? How about piping it into oil fields, coal seams or deep deposits of briny water?
That's called carbon sequestration: disposing of carbon dioxide after it's produced, rather than trying to hold down the production in the first place. It's not a new idea, although it hasn't gotten much public attention in the United States.
Lately, however, interest in sequestration has been growing. The Energy Department is spending some $29 million to study it this year, more than twice last year's total, and it has asked for 50% more next year. Secretary Bill Richardson added sequestration to his climate-change strategy last summer.
"Look at the really long term--30, 50 or 70 years into the future," Richardson said. "Carbon sequestration could offer one of the best options for reducing the buildup of greenhouse gases, not only in this country but in China, India and elsewhere."
Both China and India have coal reserves that could produce lots of carbon dioxide if burned without controls. Developing nations are being asked to limit their future greenhouse gas emissions as they expand their economies.
The future of carbon sequestration should interest anybody who pays for electricity. Power plants produce about one-third of this country's man-made carbon dioxide emissions. The costs of extracting carbon dioxide from smokestack gases--a big technical challenge--and transporting the gas to a final resting place would make electricity more expensive.
The Energy Department hopes to find technologies that cost $10 per ton of stored carbon, which might add 2% to 5% to consumer electric bills.
Nobody is talking about abandoning the better-known prescriptions for cutting back on carbon dioxide: Use energy more efficiently so power plants and vehicles needn't burn so much coal and gasoline, and put more emphasis on alternative energy sources.
But the world might also need the carbon-storage approach to reach greenhouse gas goals, researchers say, and it's time to start studying it.
The wide-ranging menu of approaches includes some that might become useful within 10 to 15 years, and others that would take longer, says Doug Carter, who directs the Office of Planning and Environmental Analysis in the Energy Department.
