# Water powered generators?



## travelling-man (Jun 17, 2011)

Does anyone here have any experience of installing water powered generators please and if so what's available and at what sort of cost?


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## canoeman (Mar 3, 2011)

Be aware water is an important commodity and rights to use or any interruption of flow a serious matter, yes I know you don't intend damming hopefully but take care

Interesting blog with info on water wheels Permaculturing in Portugal


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## travelling-man (Jun 17, 2011)

It's just an idle thought really. We're thinking of moving and one place we have an eye on has a largish weir pool on the property and I'm just wondering if it could be harnessed to give power to the house. 

'Er indoors isn't too impressed with the idea of moving at all though!


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## canoeman (Mar 3, 2011)

If it already has a weir pool then there should be some precedent for some type of wheel


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## travelling-man (Jun 17, 2011)

There's several ruins (walls are good but not much else) at the water's edge so I'd guess one at least must have had a wheel on it at some time if the distant past.


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## bikersteve (Feb 4, 2011)

Your hoping so ? He,he..


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## Striple (Feb 13, 2013)

I don't have personal experience but have a friend in the alternative energy business who swears by the PowePal low head units. You need a reasonable flow rate but the units will operate from half a metre head to three metres. Output is proportional to the head, the basic unit generates 1000W with three [email protected] with 1 metre. The european spec units output regulated 220V 50Hz. These are not necessarily the best or cheapest solution but are pretty much an out of the box setup with much simpler installation and commisioning than more up market systems.

Are you looking at this as a supplement to another source e.g. Solar PV or wind turbine? given the relatively low output but 24/7 production t,his sort of kit works well with a battery bank and inverter so you can pull much higher loads for short periods. 

Google shows a Portuguese distributor worth checking with them for prices, it is installable by a competent DIY type but does require some building work. 
Additional costs would be charge controller, battery bank and inverter if you intend it as a primary power source. 

Doing it properly is not cheap and if yoo have a mains supply the economics in payback terms aren't good it's more a case of how much being independent and off-grid is worth to you.


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## travelling-man (Jun 17, 2011)

IF and at the moment it's a very big IF I was going to do it, I'd want considerably more than 1000 watts of power and as previously said it's not much more than an idle thought just now.

The river is part of the Mondego river system and has plenty of flow/torque at the weir pool and I'm hoping it would be more a case of an engineering exercise to give me significant power but if it can't be done properly, I'd rather just go the traditional route & pay the bills!


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## Guest (Feb 14, 2013)

*More info*

Hi, I've specced and installed domestic and laboratory wind generators, PV and water powered turbines. Could you give me numbers to look at and I'll check if it's possible, how much power do you want kW and hours? what head of water is there? and what flow rate is available (take a guess)? Will it be continuous or just when you need to drawer power? If the latter what ratio between "power on" and "power off"?



travelling-man said:


> IF and at the moment it's a very big IF I was going to do it, I'd want considerably more than 1000 watts of power and as previously said it's not much more than an idle thought just now.
> 
> The river is part of the Mondego river system and has plenty of flow/torque at the weir pool and I'm hoping it would be more a case of an engineering exercise to give me significant power but if it can't be done properly, I'd rather just go the traditional route & pay the bills!


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## travelling-man (Jun 17, 2011)

I've no idea whatsoever about flow rates etc but if it's of any help, the river is about 25 yards across, the weir pool is actually on the confluence of two rivers and is about 50 or 60 yards across, the fall at the weir about 4 or 5 feet and there's also what appears to be an old mill race actually on the property and I'm sure that could have a sluice added to it if necessary.

I guess I'd be wanting something in the region of 4500 watts available. 

I don't know if this is a dumb question but why couldn't one take a 4500 watt diesel generator, remove the driving engine and instead power it via a water wheel and belted drive via different sized/variable pulleys and (if necessary) a sluice to drive it?

I'm assuming of course the generator has automatic voltage/over voltage control/limitation.


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## canoeman (Mar 3, 2011)

Bookmark this site Water Wheel Electricity
found it useful when I was considering an old olive oil factory in Serpins


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## Striple (Feb 13, 2013)

canoeman said:


> Bookmark this site
> I found it useful when I was considering an old olive oil factory in Serpins


The formula at the bottom of the page is handy and fairly realistic, the problem with home generation is usually storing the energy not producing it, 1kW generation is 
@750kWh a month which is rather more than most people use. 

Running a diesel set would need 5HP at the input shaft, allowing for gearing/transmission losses you would be looking at 8HP at the wheel.

Having said all that I have seen a house run by 3 home made wheels turning 24V truck alternators with homebrew charge controllers that dump to the immersion heater when there is no power draw. It's amazing what a home tinkerer can achieve with determination and Google!!


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## Guest (Feb 14, 2013)

Sorry don't think I can help, wooden water wheels are not my area.


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## Guest (Feb 14, 2013)

If you are looking at 5kW then is going to be AC and 50 (or 60 Hz), so direct drive will be 3000rpm and no wooden water wheel turned by the weight of water will do that. If it has 1:100 geared rev convertor (wheel turns one revolution to the generator turning 100 revs) then a small wheel may be able to do the 30 rpm but a load on the generator would require 100:1 load on the water wheel . The Water wheel would need to hold 100 times the amount of water just to overcome the electrical load. That’s why they are not used in this format. 

The solution is not using a wooden wheel powered by the potential energy of water but using the kinetic energy from the flow of water onto a turbine impeller directly coupled to an AC generator. The most economic set up, if building our own, for 5Kw would be a PaT (Pump as Turbine) coupled to a modified 3 phase motor (running as a single phase generator). The problem is you’d need minimum 2 bar water pressure at the base of the penstock so a 20m head. 





travelling-man said:


> I've no idea whatsoever about flow rates etc but if it's of any help, the river is about 25 yards across, the weir pool is actually on the confluence of two rivers and is about 50 or 60 yards across, the fall at the weir about 4 or 5 feet and there's also what appears to be an old mill race actually on the property and I'm sure that could have a sluice added to it if necessary.
> 
> I guess I'd be wanting something in the region of 4500 watts available.
> 
> ...


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