| Archive for Downsizer For an ethical approach to consumption |
| Hairyloon |
Water PowerI am giving some serious thought to hydro power.Preliminary investigations suggest there must be a catch, 'cos the return can't be that good. As a start point: 3kW turbine £3.5k A wild guess at £1.5k to install ~ £5k. 3kW, 24 hours/day, 365 days/year = 26280kWh, at 20p/kWh =£5256 per annum. What have I missed? Apart from the water abstraction license. Might have underestimated install, but there is a pretty big error margin there. 
I have a possible site, but it is quite a way from where the power needs to be, so the cost of the cable will be a significant factor. Anyone know any good places for electric cable? And big rolls of plastic pipe? Or better places to buy turbines? |
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| vegplot |
Water is a an extremely cost effective (and profitable) method of generating electricity. However, I think you've underestimated installation costs as I would have expected a small scale hydro installation to be installed for no less than 10k but this is very dependant on the situation.
Hydro is looked on favourably by organisations such as Snowdonia National Park, for instance. |
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| Hairyloon |
Don't see how, none of it is rocket science. OK, my estimate assumed I'm not charging me for the work. 
All you need is somewhere solid to mount the machine, a long pipe to create the head, and a long cable to deliver the power. The pipe and cable will obviously need some engineering, but I can't see it costing that much, even when you include the cost of getting the MCS ticket. Even at £10k, it is still a pretty good return. |
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| vegplot |
The penstock can be quite expensive depending on how much pressure it is required to stand (tapered pipe reduces cost). You also need substantial footings and mid supports to stop the penstock from trying to crawl its way down hill (flow rate and internal resistance drag cause a downward force). If you're doing the labour yourself the costs will be greatly reduced - it is a labour intensive project, the technology is simple.
Be aware of suction pressure at the inlet, this is almost the same as the dynamic pressure at the outlet - it will happily rip your arm off given sufficient head. Inlet are protected with shutters so you can drain the pipe safely prior to undertaking any work. even small installations can be tricky in this regard and only really differ from big boy stuff in size and cost. Returns are good though. |
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| john of wessex |
Bear in mind though that you wont get 3kw all the time, the load factor will not be 100%
A lokal 65kw installation is turning out 1kw at the moment due to low water levels. Try talking to Mendip Power Group for advice. http://en.wikipedia.org/wiki/Mendip_Power_Group |