"It's using a natural process and taking the waste from other biological processes, capturing gases which are dangerous for the atmosphere," says Sutton.
The delay in awarding the prize illustrates how even the most generous incentives for finding ways of capturing gases linked to global warming may prove ineffective.
Most proposals to capture gas involve injecting it deep into the earth.
They fear China would be more able to "capture" gas by building massive pipelines overnight.
Sometimes he scrambled up volcanoes to capture gas that had risen hundreds of miles from below the earth's crust.
New technology to capture gas from coalfields has recently boosted supplies, which could help keep prices down.
The other two are piping the captured gas towards a place underground where the rocks will trap it, and then actually trapping it there.
The main challenges in this case are reducing manufacturing and running costs to make the devices commercially viable, and finding reliable and inexpensive ways to store the captured gas.
