Over the past century or so many designs of hydro plant have been designed and built. It is perhaps ironic that the tributaries of the Severn have several designs of historic and technological interest to us. At Worcester, on the last mile of the River Teme by Powick bridge was a generating station supplying the first electric street-lights in a British Town. Dating from the early years of the 20th century, the buildings are still there, with some historic notes and relics visible at one side. At Warwick Castle on the River Avon, from a similar period, a hydro-electric generating station powered all the lighting in the castle. The museum in the weir-house there contains several generations of turbine and dynamo for visitors to see.
At Ludlow however, is a modern hydro-electric scheme on the Teme, which has a digital display indicating continuously the power output of the generator installed at the weir nearest to the Castle. There is also a small generating capacity at the Clywedog Dam.
The designs recommended for future application to weirs on the English Severn would appear to be able to generate enough electricity for between 500 and 1000 homes at each site on the main river – for much of the year. Two designs (the ‘Kaplan’ and the ‘Archimedes-like’) can be implemented in such a way as to minimise small-fish entry, and to maximise power generated by using two or three generators at each location – so one or two would be used when there is a small flow available, rather than use a single large one at low efficiency.