Capturing carbon : We have the technology, why aren't we doing it?
Contributed by: Dr Caleb
Last Updated February 7, 2007
CBC News
Scientists call it carbon sequestration — a big geological word that means putting the gaseous carbon dioxide from fossil fuels back in the ground where it came from, rather than in the atmosphere where it is contributing to global warming.
In the battle to contain climate change, pumping carbon dioxide (CO2) back into old coal seams or natural gas reservoirs has become one of the hot topics among scientific and government planners.
The Bush administration in Washington has just sped up its $2 billion Clean Coal initiative and says it wants a sequestration strategy in place by 2012. As well, the UN's Intergovernmental Panel on Climate Change touts sequestration as one of the important mitigating factors for climate change and points out that Canada, with its wealth of tapped-out oil and gas wells, provides a natural home.
But the high costs that go along with trapping CO2 at the smokestack, compressing it into pipelines and then shipping it to a disposal site where it can be injected deep into an underground cavern are making energy execs and utility managers nervous.
For a big coal-fired utility that emits 20 million tonnes of CO2 a year, such as Ontario's aging Nanticoke or Alberta's Sundance, a six-unit generating plant that burns 250 rail cars' worth of coal every day, this could mean a $1-billion retrofit, albeit one that would be passed along to consumers over 40 years or so.
Indeed, the arguments for and against sequestration are not unlike those for insulating homes: It's one thing to insist on much higher energy standards for next year's subdivisions (read the next generation of coal-fired power plants), quite another to go in and redo a draughty, old ranch-style bungalow from the 1950s.
It's working now
Still, there are three big capture programs already underway in the world, not to mention scores of more modest pilot projects, including some in Canada that have been on the go since the late 1990s. The big three:
* Norway's national oil company is stripping one million tonnes a year of CO2 from the natural gas it is mining under the North Sea and re-injecting it back into empty wells.
* British Petroleum is doing the same with an oil well in Algeria and planning a similar project in California.
* And a (coal-gasification) utility in Beulah, North Dakota, is shipping approximately 1.5 million tonnes of CO2 each year over 200 kilometres by pipeline to our very own Weyburn, Sask., where it is being re-injected into an old oil field to help with the recovery of new deposits.
http://www.cbc.ca/news/background/kyoto/capturing-carbon.html
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