TNAG-1498-FCO40-2056-Guangdong-nuclear-power-station-project-at-Daya-Bay-safety-c-1986 — Page 82

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there is no guarantee of the timing or of the availability of the supply, and even the most optimistic proponents of doing more to harness the wind agree that after 40 years of successful

exploitation they might contribute 2% of our electricity supply.

THE TIDES

There is excitement about the potential of harnessing the tides, and

the Government has supported exploration of the possibilities of a

tidal barrage scheme on the Severn Estuary. We are also continuing to look at wave power more generally.

If the Severn Barrage Scheme was completed it would harness the

second greatest opportunity for tidal power in the whole of the

world. There are no similar opportunities available in Western

Europe and if the Severn scheme was eventually completed and it

could not be completed before the end of the century - the maximum

it could produce would be 5% of Britain's current electricity

demand, or an amount equivalent to one fifth of the increase in

electricity demand that had taken place before its construction was

completed.

Tidal power also has its problems. You only have daily peak loads,

you do not have the consistency of supply; tidal electricity will

not coincide with the peak loads of demands.

We should take advantage of a tidal system if it is found to be at

all viable. But even if it was viable in the Severn, and we looked

at all the other potentially viable places such as the Mersey in the

United Kingdom, the total contribution of using every tidal estuary

that could be tolerably used would be, at the maximum, an 8%

contribution to our current electricity demand, equivalent to

meeting the increased demand of electricity for a 4-year period.

GEOTHERMAL ENERGY

We have hopes that we can obtain useful energy from the hot dry rocks below the earth's surface and have recently substantially

increased our research programme. Our experiments into geothermal energy have gone well, but they are far away from producing anything that can be commercially applied. There is plenty of heat below the earth's surface, the difficult task is extracting that heat and providing the energy where it is required.

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