Severn Tidal Barrage

Location: Severn Barrage, UK

Sector: Social Good

"landmark conservation and engineering project for the 21st century of a scale never before attempted in Europe"
Jonathon Porritt.

For the past few years Marks Barfield Architects have been one of a determined and growing team of entrepreneurs, scientists, engineers, politicians  and  financiers on a mission to finally realise one of Europe’s biggest renewable energy projects – The Severn Barrage. Ever since the idea arose in the 1980s about the possibility of harnessing the extraordinary power of the Severn’s tide it has always seemed to us to be a ‘no brainer’. With the news that the new nuclear program is stalled and has nowhere to dump its waste - we are even more convinced.

The Barrage can provide a massive 5% of the UK’s electricity - equivalent to 3-4 Nuclear reactors and more than 3,000 wind turbines. The energy is clean, secure, consistent and predictable. The barrage will last for 120 years plus – significantly longer than any other alternative – and at £20/MWh, it is also cheaper than any other alternative – a quarter of coal, gas or nuclear at today’s prices. The real lifetime costs of Sellafield were revealed recently to be staggering £67.5 billion! At £25 billion to build the barrage, all privately funded, we could have 2.7 barrages for the same cost.

An important part of this proposal is the use of bi-directional turbines. These harness both the in and out tides to produce guaranteed energy for 15-16hrs a day and do not hold back heads of water as high as previous proposals  – thus preserving 60% more intertidal habitat for the feeding and roosting grounds of wading birds.  An estimated 49km2 of intertidal habitat will be lost- however Defra has calculated that almost the same amount will be lost anyway due to rising sea levels. Indeed, the barrage can also act as a flood defence, saving billions in flood damage. In addition, there is a commitment to create new habitats for birds as part of the project to the tune of up to £1billion.The Barrage will also be a powerful force for regeneration in South Wales and the South West – an area desperately in need of jobs and investment. Sandfields, for example, is a housing estate of 5,000 people just outside Port Talbot, built to provide labour for steel and other industrial works, which then closed within the second generation and it is now left struggling with the aftershock. The Barrage is estimated to not only create thousands of jobs during its construction but subsequently will be able to export this new turbine technology around the world enabling the UK to lead the world in tidal power technology giving the area a sustainable economic future.

The calmer estuary waters upstream of the barrage will encourage tourism and recreational uses by local people. We, together with ARUP and other members of the team will try to ensure that the barrage has a positive impact on the environment in which it sits and is beautiful.

There is an urgent need to create new sources of low carbon, sustainable energy in the UK. We currently import 30% of all our energy needs, and by 2030 DECC forecasts that there will be an energy gap of 60TWh. The barrage can offset 30% of this and become an important part of the UK’s energy mix.

There is a huge amount of work to do on all fronts - political, financial, environmental, engineering, and ecological as well as lots and lots of consultation - before the Barrage becomes a reality.Where we would be now if all that investment - from the 1980s on - that went into nuclear had gone into renewable sources? We suspect we would be in a much better place than we are now. It’s not too late. Surely it is worth getting it right now and putting our energy into producing clean, long-lasting, cheap, renewable power – in this case tidal power driven by the moon. But it will require the government to show some boldness of vision.