Environmental decision making is fraught with contested views. An example in point is the proposed barrage that would span the Severn Estuary, not far from me really and technologically, rather exciting.
Yet negative environmental implications abound, more of which in a moment – for now, let’s quickly marvel at the possibilities.
The Good News
It seems incredible that just north of where I live, 50 miles or so, there exists the second highest tidal range in the world – with a difference between high and low tide of some 14 metres. The potential to harness this enormous flow of water into renewable energy is obvious.
The proposed dam, known as the Severn Barrage, would cost £15 billion to construct and would measure 10 miles across and act as a bridge between England and Wales. It is estimated that it would remain operational for around 200 years.
214 turbines would be installed and the water trapped at high tide would then be released, generating the equivalent of three nuclear power stations’ worth of energy and providing 5% of the UK’s electricity. Estimated to produce 17 billion kWh of electricity annually, the UK’s carbon emissions could be cut by 16 million tonnes each year.
The Bad News
The effects to the environment would be devastating. You can put a price on a barrage; however, you can’t put a price on wildlife and biodiversity.
The Severn Estuary is designated as a Special Area for Conservation. 85,000 migratory and wintering water birds are dependent on the mud-flats which would be lost. Coastal erosion would increase in some locations while additional silting would occur in others. There would also be the increased risk of localized flooding.
The Severn Barrage then, part of the UK’s push for increased renewables – too good to be true? In this case, yes. Conservation must come first and alternatives found. Just because mankind has found himself hideously backpedalling from an Industrial Revolution fired by coal, this gives him no excuse to trample over wildlife in a bid to clean up his act.
Sources:
Image depicting the Severn at low tide courtesy of Flickr
This is a really thought-provoking piece on the pros and cons of a potentially huge renewable tidal energy plant. After reading it, I’m on the fence. I mean, renewable energy is a really important goal. But I think Pem has an admirable point that wins me over in the end: “Just because mankind has found himself hideously backpedalling from an Industrial Revolution fired by coal, this gives him no excuse to trample over wildlife in a bid to clean up his act.”
Thanks so much Gavin. Believe you me, as I tackled this topic, I was in two minds … but, alternatives MUST and WILL exist that allow for harmony with wildlife.