Letter to the Editor: I REFER to letter from Simon Phelps. Westbury and the suggestion to set up hydro-power units in the Forest of Dean.

Whilst there is some merit in what Cllr Phelps says, the commercial potential for such units is pretty small.

Firstly the potential water level differences achievable will be small and small propeller turbines suitable for such level differences would be of relatively small capacity and low efficiency.

An example of such generation – Forest Pennant, that supplies paving and building stone, have installed a plant that generates 13.5kW of electricity, about 70 per cent of the company’s requirement for processing stone.

Typical solar household generation is 4kW so this equals just over three times they typical household solar installations which cost below £5000 each.

Cannop Ponds once had capacity to turn a water wheel. Not many such potential locations.

Reportedly Forest Pennant hydro-generation cost over £70-£80,000 in 2009/10 so not all that cost effective.

Surplus power is fed to the grid same as from household solar generation.

Forest Pennant would have been better advised to have a large bank of solar panels which would have been cheaper and easier to maintain.

Hope others with running streams or large ponds with potential to bund would like to check if they can install small turbines to make use of the hydro-potential.

I don’t hold much hope for commercial installations in the Forest of Dean. 

Venk Shenoi, Blaisdon