Coal: fuel of the future

Tom James @ 24-04-2009

geological-carbonThe British government has given the go-ahead to a new generation of coal-fired power plants incorporating carbon-capture and storage technologies in a bid to reduce carbon dioxide emissions. Clean coal has been met with criticism and the policy seems just a little bit flaky:

Up to four new plants will be built if they are fitted with technology to trap and store CO2 emissions underground.

The technology is not yet proven and would only initially apply to 25% of power stations’ output.

Green groups welcomed the move but said any new stations would still release more carbon than they stored.

Uh huh. According to UK energy secretary Ed Miliband:

Once it is “independently judged as economically and technically proven” – which the government expects by 2020 – those stations would have five years to “retrofit” CCS to cover 100% of their output.

Kind of a glass quarter-full situation then. And it might not even work. But do check out the details.

[image and articles from the BBC and the Guardian]


Where to put the carbon…

Tom James @ 15-07-2008

Aside from nuclear power, one of the most enticing possibilities for solving problems of energy security, peak gas, and global warming is carbon sequestration.

windfarmBy burning cheap and widely available coal but storing the resultant carbon dioxide rather than venting it into the atmosphere means you (theoretically) have a cheap and low-carbon energy source.

The main issue is finding a place to stick all that carbon dioxide. Dave Goldberg of the Lamont-Doherty Earth Observatory claims there is a vast area off the east west coast of Oregon under the Juan de Fuga Fuca tectonic plate which addresses many of the safety issues of carbon sequestration:

“We have insurance upon insurance upon insurance,” he said.

First, the center of the proposed location is about 100 miles off the coast, obviously far away from human settlement. Second, the impermeable sediment cap on the permeable basalt reservoir is hundreds of feet thick, creating an effective seal for the compressed CO2. Third, when CO2 mixes with water inside the basalt, over time it turns into a variety of carbonates, which are, essentially, chalk. Fourth, if there were an unforeseen leak, in deep water, CO2 forms into icy hydrates in the water, preventing it from floating up to the surface.

As to the UK: what about using the recently emptied North Sea oil wells as a carbon sink?

It is becoming clear that if we are to create a genuinely zero-carbon (or even low-carbon) economy we are going to have to embrace nuclear power and carbon sequestration, as suggested in Plan D of David David J. C. Mackay’s excellent (but unfinished) free ebook Substainable Energy – Without the Hot Air. The evidence is mounting that wind power, solar thermal, and photovoltaics don’t work well enough.

[story from Wired][image from Scott Ableman on flickr]


Germans putting CO2 underground

Tom James @ 01-07-2008

Carbon sequestration or carbon capture and storage (CCS) is an enticing possibility for those who like their global CO2 levels below 390 ppm but aren’t too keen on nuclear power.

sa-megetThe basic idea is to carry on burning fossil fuels for energy, but instead of venting the waste CO2 into the atmosphere, bury it underground. Now CO2SINK, a European research project, have created the first underground carbon dioxide storage site at Ketzin, near Berlin:

It will pump up 60,000 tonnes of the greenhouse gas into porous, salt water-filled rock at depths of more than 600 metres (656 yards) over the next two years, the centre said.

This obviously won’t solve all the problems. After all it is probable that our fossil fuels will run out at some point. “Clean” fossil fuels might provide a useful stopgap before we decide on our long term energy mix.

[story via PhysOrg][image from Jacob Botter on flickr]