Jenny Haworth: Carbon capture fine in theory but untested

Published on Friday 30 January 2009 21:21

THE technology the Scottish Government is hoping will clean up fossil-fuel power stations has yet to be proven on an industrial scale.

If it works, so-called carbon capture and storage (CCS) has the potential to cut 90 per cent of the greenhouse gas emissions from fossil-fuel power stations.

This would allow power stations to be cleaned up so they could continue to be used to generate electricity, while enabling climate change targets to be met. However, there is no clear evidence that the technology will work. Although it has been used in pilot schemes, it has yet to be demonstrated on a commercial scale.

Duncan McLaren, chief executive of Friends of the Earth Scotland, said: "What any expert will say is it's technologically proven at every stage of the chain, but putting those steps together at the scale of a large power station and doing so in a commercially viable way is yet to be proven."

There are promising signs from small-scale projects around the world. In east Germany, a plant a tenth of the size of a normal power station has been built using CCS.

Norway's oil industry has been capturing for years and storing it under the North Sea, and projects similar to CCS are up and running in Dakota, in the United States, and Algeria.

In the UK, a competition is taking place to develop a CCS demonstration project, with Westminster prepared to fund up to 100 per cent of the cost of the technology. ScottishPower has entered Longannet, one of Scotland's two coal-fired power stations, in the competition.

The winner is due to be announced in the spring and the project should be operational by 2014.

CCS involves taking from power stations, compressing it then transporting it along a pipeline and storing it deep underground where it cannot escape into the atmosphere.

After the gas is captured, it is stored indefinitely deep under the ground, such as in the spaces within rocks. It is believed there would be suitable locations beneath the North Sea, as well as in many other parts of the world.

However, there is concern that applications to build pipelines to transfer the liquid gas could meet with environmental concerns, holding up projects.

The UK Committee on Climate Change has said all coal-fired power stations should be using the technology by the early 2020s, with gas-fired plants following soon after.

It spelled out that without the "decarbonisation" of electricity generation, there was no possibility of achieving the government's targets of an 80 per cent reduction in greenhouse gas emissions by 2050.

However, the report also highlighted that the unproven technology will be expensive.