Research is under way at the National Energy Technology Laboratory on so-called "carbon sequestration" technology that would capture CO2 gas before it is released into the atmosphere and inject it, either deep into the ocean or into the ground.

CNN: Energy debate may soon turn on 'cleaner' coal

But the idea of simply getting carbon credits for storing CO2 in the ground, which air-capture enthusiasts used to see as the natural use for the technology, is no longer plausible.

ECONOMIST: Combating climate change

The Liberal Democrat MSP said that initially the power station was to have 400 megawatt of its gross output (300 megawatt net) processed through carbon capture and storage technology, which would leave 75% to 80% of the plant' s CO2 emissions unabated for an indeterminate length of time.

BBC: Hunterston member's debate