permaculture

[Saor Stetler <saor@ycbtal.net>]

Sea energy to power Britain

Waves and tides could generate 20 per cent of electricity and replace 
nuclear fuel, report says

Juliette Jowit, environment editor
Sunday January 29, 2006

Observer

Surrounded by some of the world's roughest seas, Britain could generate 
a fifth of its electricity by harnessing the power of tides and waves.

The potential of marine energy is revealed in a report by the 
government's energy advisers. Wave and tidal power could replace the 
electricity that is currently produced by UK nuclear power stations, 
they state, and could prevent the need for Britain to rely on increased 
Russian gas imports.

Harnessing the sea, particularly around Cornwall and the north of 
Scotland, with machines that capture the movement of tides and waves, 
has long been a dream of scientists. In recent years the quest for 
clean, renewable power to replace polluting fossil fuels has taken on a 
new urgency as the world battles to reduce carbon emissions from coal, 
oil and gas which are the biggest cause of climate change.

Until now, marine power generators have been limited to a couple of 
small prototypes, considered too futuristic to take seriously as the 
answer to the planet's energy problems. The study by the Carbon Trust, 
which advises the government on clean energy, challenges that. It 
predicts tidal and wave power generators could be supplying a 
significant amount of power to the electricity grid by the end of this 
decade.

Its report follows a £3m, 18-month research project into how marine 
energy generators could work, part of £50m of support programmes 
promised by government. The report, which is being studied by ministers, 
says that the opportunities for machines which use the power of waves to 
produce electricity are 'considerable'. Based on the number of sites 
with reliable tides and waves and close enough to connect to the 
mainland, such equipment could be supplying a fifth of the country's 
current electricity needs over following decades.

Given Britain's long coastline, close to the strong currents of the 
Atlantic, marine power would also help to solve another of the 
government's key priorities - reducing reliance on imported energy 
sources, said John Callaghan, one of the trust's programme engineers.

'The UK leads the world in marine renewables technology,' he said. 
'Given our superb natural resources and long-standing experience in 
off-shore oil and gas, ship-building and power generation, the UK is in 
a prime position to accelerate commercial progress in the marine energy 
sector.'

The report was welcomed by environmentalists: 'Solutions to climate 
change and the threat and expense of nuclear power exist; we just need 
the political will to implement them,' said a spokesman for Greenpeace.

However the Carbon Trust also highlights problems. The new technology 
will need investment by the government and private companies and there 
is no reliable forecast for when it will be available on the large 
scale, said Callaghan. There are concerns that power generators at sea 
would be expensive to connect to the electricity grid, could not always 
provide power when it was needed, and may pose problems for sea life.

Dr Jon Gibbins of Imperial College, London, questioned how much marine 
power could meet Britain's aim of tackling climate change because that 
would require global agreement to reduce carbon. Many countries did not 
have suitable sites and could not afford the new technology, he said. 
'That doesn't mean we can't try it [marine power] and won't do it,' he 
added. 'But if you want to rely on marine technologies to displace 
fossil fuel use you're being very optimistic.'

The World Wildlife Fund said it was against tidal barrages (which are 
not covered by the trust's report) that create huge physical barriers to 
marine life in sensitive estuaries, but it supported the harnessing of 
tidal and wave power as long as sites were chosen carefully.

Callaghan said the trust had identified 'tens, possibly hundreds' of 
suitable sites for wave power, principally off south-west England and 
north-west Scotland, and a dozen sites for tidal power turbines, half of 
them in the Pentland Firth between the Scottish mainland and the Orkneys.