New wave energy for Britain?

The U.K. once powered its industrial revolutilon with coal. Now that nation is looking to the sea for some of its future power. The plans for a huge wave-powered electricity generation scheme are getting encouragement from government leaders. The plans estimate 5% of the UK's entire power needs could be met with single tidal plant. The "Guardian" points out it's not without drawbacks or problems, "one of the most ambitious civil engineering challenges in the world, would significantly affect the visual and marine environment more than 30 miles around it and have mixed long term economic and ecological impacts, according to a report from the Sustainable Development Commission."

That Commission says overall at least one-tenth of UK's power needs could be met with tidal energy. The Severn project is expected to cost as much as $40 billion US, and would include 200 turbines to convert the tidal energy.

The map showing where the tidal installation would be on the western edge of Britain is from the BBC website. The Severn is a good locaton because its geography creates high high tides and low low tides. The power is generated by trapping high tides and then letting the ocean water flow back down to the low tide level through generating turbines. Essentially converting the force of gravity into electricity the way river dams do. You could think of this as damming a large estuary.

Here are four more conclusions of the Sustainable Development Commission as it deals with Severn plans:

• "A Severn barrage [tidal barrier] must be publicly led as a project and publicly owned as an asset to avoid short-termist decisions and ensure the long-term public interest

• Full compliance with European Directives on habitats and birds is vital, as is a long-term commitment to creating compensatory habitats on an unprecedented scale

• Further investigation of the ‘environmental opportunity’ that might exist for combining climate change mitigation with adaptation through a habitat creation package that actively responds to the impacts of climate change over the long term

• Development of a Severn barrage must not divert Government attention away from much wider action on climate change."

For us kids there's a good summary of tidal energy plants on this US government site. It points out the two operating plants in existence are at "La Rance, France; the other is in Annapolis Royal, Nova Scotia, Canada. The US has no tidal plants and only a few sites where tidal energy could be produced economically. France, England, Canada, and Russia have much more potential."