April 29, 2008

A fix for gas emissions? Pond scum could help

OTTAWA -- As Canadian energy companies face growing constraints on their greenhouse gas emissions, researchers believe they have found an answer in pond scum.

Backed by oil companies and utilities, Canadian researchers are plowing ahead with plans to develop algae farms that will convert carbon dioxide from oil sands projects and coal-fired power plants into biofuels, chemicals and fertilizers.

Algae ponds that use photosynthesis to feed on CO{-2} are common in warmer climes, but until recently, few thought they would be productive in Canada's harsh conditions. Now a consortium led by the Alberta Research Council has completed research that suggests the algae would thrive under northern light and temperatures, with an appropriate covering for winter months.

"What we are doing is transferring [the algae systems] into more temperate climes, which is a big step and something that no one ever believed would be viable; but we have demonstrated that that's not true," John McDougall, chairman of the Alberta Research Council, said in a telephone interview after presenting results of the first phase of the project to research partners.

"We think this can take a major bite out of the CO{-2} problem, particularly for large industrial point sources. Our work has shown to date that, for the large industrial emitters, this kind of a system would potentially take up about 30 per cent of their emissions."

All told, he envisions a fleet of bioconversion facilities at tailings ponds across the country, capable of eliminating 100 million tonnes of CO{-2} emissions a year - equivalent to more than a third of Alberta's current production of greenhouse gas emissions.

The researchers - including scientists from Alberta, Saskatchewan, Manitoba and Quebec - believe they can boost the productivity of the system so that CO{-2} can be removed at a cost of about $25 a tonne.

That's far cheaper than carbon-capture and storage technology, which is widely touted as an answer to Canada's industrial greenhouse gas emissions. Oil companies and utilities are developing technology that will capture CO{-2} from emissions and inject it underground for permanent storage. However, industry experts have estimated the cost of such carbon capture and storage plants would be $80 per tonne of CO{-2}.

Mr. McDougall said he believes the algae-based CO{-2} recycling will complement carbon capture and storage systems, and will be particularly useful for large emitters in Eastern Canada, where the geology is less suitable for underground storage.

The federal government released emission targets this year that will require oil sands and coal-based utilities that come on stream after 2012 to virtually eliminate their greenhouse gas emissions, although the companies can claim credit for emissions-reduction by investing in technology that will eventually do the job.

The $20-million algae project is being funded by major Canadian energy companies, including Petro-Canada, Royal Dutch Shell PLC, EnCana Corp. and Epcor Power LP, a coal-dependent Alberta-based utility.

The researchers will spend the next two years improving productivity of the algae system, including efforts to generate growth deeper under the surface of the pond to reduce the area required.

They will then construct a demonstration project at a site to be selected. Assuming the technology proves commercially viable, the consortium expects companies to begin building the recycling facilities at industrial and mining sites across the country by 2015.

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