Monday, January 26, 2009

Tidal energy from the Severn Estuary: Yes...but not at the price of estuary destruction!

The Severn Barrage issue is in the news, with the shortlisting of five tidal energy options. Its a mixed picture, with some good and some bad sides.

Lots of talk about tidal energy and not enough debate and action on having a proper energy strategy. A correctly prioritised energy strategy would put energy efficiency top of the list - why not insulate all homes at no cost to the occupiers (such a scheme quickly pays for itself in saved energy, and thus lower bills, and rapidly reduced carbon emissions)??

Its good news that tidal lagoons will be considered. They offer large amounts of affordable and renewable power at low environmental cost to the estuary.

Its bad news that tidal reefs/fences are not on the list (though they will apparently get money to develop the idea). They too promise lower impacts.

Its even worse news that the Brean/Weston-Super-Mare to Cardiff barrage is on the shortlist. Its environmental impacts are huge and amount to destruction of the estuary. This fails the EU Directive on Habitats and Birds.

More here:


  1. Re Insulating homes - Bristol City Council did this to my home for free just before the last election a year or so ago. And I have a lovely toasty house now.

    I am an owner occupier in receipt of no benefits so can I assume this was offered to everyone in the council area?

    Though they did it just before the last round of elections, I live in a marginal ward and the incumbent council were not trying to buy votes!!!

  2. You illustrate the benefits of a well insulated home in a nutshell - toasty!!

    Insulation has not been carried out free on all Bristol homes though. Far from it.

    All homes in the country should be insulated to a high standard at no cost to the occupier. Govt policy on insulation needs to go much further and much faster!

  3. We are back to the lack of joined up thinking at central government again. What's greener, providing 5% of our energy from renewable sources, or, reducing the need for energy by 5%? Renewables are much more carbon efficient than fossil fuel energy sources but any energy production method involves some carbon emissions somewhere along the line.

    The government like "big projects" that get lots of headlines so they can say "look how green we are by investing in renewable energy". If they were really serious they would be looking at reducing the need for the energy in the first place and spending the money needed.

    Glenn has already mentioned insulation – a report by the Energy Efficiency Partnership for Homes in August, estimated that a combination of installing cavity wall insulation, solid wall insulation, installing floor installation, upgrading loft insulation and other methods like better insulation of doors and hot water cylinders would save 17.4 million tonnes of CO2 equivalent emissions per year. This is roughly equivalent to 4.5 times the entire carbon emissions of the City of Bristol each year. However, the £1 billion insulation industry is predicting that the rate of retrofit insulations will actually fall off after 2014 due to a lack of government long-term guidance and commitment to the industry.

    In addition, the Government wants to build 3 million new homes by 2026. If those 3 million homes are built to current energy efficiency standards they will increase our demand for energy by about 3% - effectively using 60% of the potential renewable energy created by the Barrage.

    For about £16 billion (roughly two-thirds of the figure anticipated for the Severn Barrage), it would be possible to upgrade all those new homes to low energy standards (based on figures for ‘passivhaus’ construction in Freiburg, Germany) which would reduce their energy consumption for space heating by 80%, roughly halving their their overall energy needs and reducing carbon emissions by about 8.5 million tons per annum.

    A lot of discussions held recently in the Bristol area have been about the waste to energy incinerator, and how the need to “feed the beast” might detract from the higher priorities of reduce, re-use, and recycle. I feel the same way about the Severn Barrage, it is such a big headline making project that it might even encourage people to use more energy – “it’s OK, it’s green” – rather than concentrating on methods of energy reduction.


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