Tuesday 9 September 2008

The 'magic bullet' of energy supply

Lewis Smith, Environment Reporter

Carbon capture and storage is not the only solution to climate change in the offing but it is regarded widely as the best. If it can be made to work.
There are some, such as supporters of Greenpeace, who believe that fossil fuels should be dropped altogether as a source of energy; most analysts take a more pragmatic view, even if the proposed technology is very expensive.
Fossil fuels are one of the main contributors to climate change but they also offer an easily harnessed and well-understood source of energy.
Carbon capture and storage (CCS) offers the prospect of a magic bullet: a way for the world to remain dependent on fossil fuels without sending global temperatures soaring to catastrophic levels.

The key to its appeal is the prospect of the West being able to go to China, India and other developing nations with technology to reduce greenhouse gas emissions substantially while not threatening their economic growth.
By extracting carbon dioxide from fossil fuels as they are burnt to provide energy, the main argument against oil, gas and particularly coal is removed.
The system is not expected to be perfect — at least 10 per cent of carbon dioxide emissions may still escape into the atmosphere to act as a greenhouse gas — but it should ensure that most emissions are captured. The CO2 can then be stored safely so that for many years to come, most likely millennia or even millions of years, it will remain trapped deep in the Earth and out of harm's way.
Oil and gasfields have been identified as ideal places to store captured CO2. Not only are they suitable for locking in gas, the CO2 can also make itself useful by increasing the underground pressure, forcing yet more oil or gas within reach of extraction pipes.
Moreover, from a British point of view, oil and gasfields approaching the end of their useful lives have the distinct advantage of being on our doorstep.
CCS increases the Government's options for maintaining security of energy supplies. Coal provides about a third of the country's electricity and, if that were to be reduced, new sources would be needed.
In a century when Britain is increasingly dependent on oil and gas supplies it seems wise to avoid becoming any more beholden than necessary to unstable or aggressive nations.
Introducing CCS technology would come with a financial cost: it is expected to add at least 20 per cent to the price of electricity.
Such a rise would, however, be about the same as that expected if enough money were invested in renewable sources to reduce society's dependence on fossil fuels significantly.
Furthermore, Sir Nicholas Stern, in his seminal report on the costs of climate change, calculated that if the world is to prevent temperatures rising by more than 2C, the absence of CCS will increase mitigation costs by 60 per cent.