Bell Ingram - serving UK's land and property owners to make the most of their assets
Micro Wind and Hydro Specialists
Hydro and Small Wind
Wherever there was a mill in the past or wherever there is a cascade of water near a building or grid connection, there may be the potential for a private or commercial electricity generation scheme. A well-designed and installed hydro scheme will last many decades and can be the most cost-effective of all renewable energy sources with revenues on small schemes of over £700 per kilowatt of installed capacity, giving payback terms of seven to ten years.
One British company, Gilbert Gilkes & Gordon, has been installing micro hydro turbines throughout the world for over a century and is busy refurbishing their original systems.
A new interpretation of the Archimedes screw is allowing the redevelopment of many old mill sites having relatively low environmental impact and installation costs.
Even the smallest hydro developments are subject to strict environmental and planning controls and a project is likely to take two or more years to come to fruition. The experience of hydro scheme designers and builders is extremely important.
The big reduction in the feed-in tariff payable for wind generation since 2010 means that now only the most exposed places are cost-effective for wind turbines, but a site with a mean windspeed over 6.5 metres per second could still host a profitable generator.
For example, a 50kW turbine might be installed for £300,000 or less. It might generate 165,000 kWh per year worth £34-36,000, or more if a high proportion of the generated power can be used locally in some commercial process. After allowing for inflationary increases in operation and maintenance costs, electricity prices and feed-in tariffs, this should be profitable over 15 years or more.
The most attractive project size is probably 500kW which can just slip below the thresholds of a 50m rotor tip height planning limit and the step down in feed-in tariff rate.
Wind speed and consistency must be carefully assessed on site prior to installation to establish whether exposure levels are good enough to generate sufficient output. The main obstacles thereafter are grid connection costs and obtaining planning permission, both of which issues are very sensitive to location. Good independent advice from the earliest stage from an experienced practitioner is vital.