I keep thinking about this trip I went on last weekend – a tour of micro-hydro plants organised by the South Somerset Hydropower Group. It was a good deal – for £60, we got lunch, coffee x 3 and bussed around 6 quite different micro-hydro sites, with plenty of expert commentary, not least by some very proud owners – full details here. At this time of year as well, these plants are working nearly flat out, because there has been so much rain (and lots of mud too – I’m such a townie!). Load factors of 70+% are right now about the norm.
Anyway, here’s one of my favourites of the day, Hainbury Mill which has an archimedes screw. The benefits of this technology are that it is; very fish-friendly, virtually no filtering out of river debris required and it’s really quite unusual to look at.
With feed-in-tariffs coming in from the 1st April, it’s anticipated that a mini-boom might come about for micro-hydro. Let’s see – I wouldn’t hold my breath for any government scheme scaling up quickly and efficienctly. For all that, this is different to the pre wind rush of just over a decade ago. Back then, complex regional monitoring of windspeeds was required to get an idea of where the best locations were. This time, the UK already knows where its long-retired 30,000 mills are located and technology has come a long way in the last few years, to enable the extraction of power from low head sites. And micro-hydro has much higher availability, works at a higher load factor – even contributing baseload power than those poster childs of the micro-generation sector – wind and solar.
One more picture – I thought this mill won the beauty prize – Hewletts Mill.