Here's a novel way to generate some (extra) electricity: Bath, UK-based company 2OC has unveiled a plan to capture wasted pressure from the natural gas grid, Cleantech reports. By 2010 the group hopes to be able to generate 20 MW of power in east London. This is how the 'geo-pressure' system would work:Up to 1 GW of Electricity Could be Generated
By attaching a 20cm tall "turbo expander" on the pipeline at a natural gas pressure reduction station the energy from the pressure reduction procedure could be harvested and used to generate electricity. 2OC estimates that if geo-pressure were fully exploited in the UK, the nation could add an additional 1 GW of electricity to the grid and avoid emitting 1 million tonnes of CO2 into the atmosphere.
I wouldn't go so far as 2OC does in calling it carbon free electricity—though technically correct, as it depends on natural gas, which if it weren't going to be burned wouldn't likely need to have its pressure reduced in the first place—but it is an interesting use of energy which would otherwise be wasted.
More on geo-pressure: 2OC
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