Planning permission has been granted for a micro hydro scheme on the River Don at Kelham Island in Sheffield, despite the fact that it will generate enough electricity to power just 20 homes per year, provided there is enough rainfall and the scheme is managed and operated with maximum efficiency. The scheme in Sheffield is not unique - many thousands of sites across the UK have been identified as 'suitable' for micro hydro development and they are being universally sold as a serious 'green' alternative, a key part of Britain's energy future and a lucrative 'community-based' investment that will help power the nation, paying sustainable dividends to those willing to part with their cash. This blog is a public resource designed to demonstrate the negative ecological impacts of 'low-head' or 'run-of-river' micro hydro schemes and asks why UK taxpayers are funding their development despite the fact that the evidence from the world over is that they do far more environmental damage than good.

Watch the film, 'Kelham Island Hydro', and ask whether what boils down to be a few kettles' worth of hydro-generated electricity is proportionate to the decimation of our little-understood and very fragile river ecosystems.

If you have problems viewing the film from here, please view on Vimeo or watch on Google where you can also download to your pc.

Saturday, 23 June 2012

Screening and Cleaning

One of the issues raised in Kelham Island Hydro is the importance of adequate screening to prevent juvenile fish from entering the turbine channel from both up and downstream positions. The ideal size is just 3mm x 3mm. To give an idea of how difficult maintenance of such a screen can be, take a look at the before and after pictures below which show the accumulated debris caused by recent flooding at Niagara weir. The 'trash-screen' is at the upstream entrance to the fish-pass.



The screen in this case is intended to allow passage of fish and is therefore deliberately large, but if you imagine the amount of debris that will frequently accumulate on much smaller screens intended to stop fish passage, i.e. those that need to be installed on a hydro-power channel, then you can also imagine the levels of maintenance that will be required to ensure that adequate levels of water flow through and keep the turbine running at an optimum. Cost effective? No maintenance costs were factored into the published feasibility survey for Kelham Island.

The maintenance of Niagara fish-pass is undertaken by volunteers working for SPRITE and I'm hugely indebted to that organisation for providing these illuminating images. Keep up the brilliant work!

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