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.
Sourced – The Observer