Hello Morgan,
my knowledge is only based on the water wheels that used to be all over the UK. Some are still there , many have gone. My main use of a water wheel will be for actual power ...ie to run a circular saw , or a lathe or power hammer ,or even a loom . Basically anything that used to be run by water power years ago . All the technology is still there to be seen , you just need to go to the right museum . I do intend to run an alternator off of the wheel as well . This is where things get tricky ... I will start with just a car alternator to charge batteries. Now a car alternator normally runs much faster than a water wheel , my w/wheel will be about 12' dia. and will turn relatively slowly. Therefore there is no point in trying to run it off of the w/wheels axle, it will hardly be turning at all . To have a huge fan belt going all the way round the w/wheel and then the alternator pulley, wouldn't work either ...the belt would cost an absolute fortune and would rot in no time .I will therefore be fitting teeth all the way round the dia of the w/wheel and they will in turn fit into something similar to a motor bike sprocket fitted instead of the pulley . This is where you have to work out different ratios to find out the speed the w/wheel will turn the sprocket on the alternator, ie if the wheel was 10' dia and the sprocket 1' dia , you have a 10 to 1 ratio . Mine will be about , water wheel = 144" dia, sprocket maybe = 4" , that should be about 36-1 ratio.....You then have the speed the alternator will run at . I am looking at finding different gearboxes to to run off of the wheel direct , instead of the alternator , so I can then turn 360 rpm through that gearbox which would be say 3 - 1 , and thus give me 1080 rpm , which would then run the alternator quiet well. Trouble is you get all sorts of power losses each time you go through a gearbox or even pulleys or sprockets . So it will be trial and error once I have the wheel made and in situ. Thats one of the problems ... another is the type of wheel you have ..ie over shot or under shot . An overshot wheel is where the water comes to the wheel along a wooden or metal shute and hits the wheel near the top , and then the weight of water turns the wheel . This is about the most efficient type , giving you about 80% efficiency. An undershot wheel is where the wheel is powered by water just flowing along as if it were still in the river...ie at the bottom of the wheel . These are about 20% efficient , a big difference. If you have a stream with a head of say 20 ft, then you can go for an over shot . If you only have a stream with no head ie it just flows along a field with no discernable fall, then you have to go with an undershot . I only have the later , so I will dig a special cutting next to the river . I will then make a small dam and from that dam a little channel will feed water to the wheel . If you put the wheel direct in the river you get problems with winter flood water washing the wheel away etc. I will also be digging a mill pond up the hill from the river and feeding that from different sources to run the wheel as much as I can , as an overshot , thus giving me more effeciency from any given amount of water stored in the mill pond. So a two pronged attack lol... I would then be able to use the mill pond when maximum power was needed and the river when less was needed. I am lucky in that I have a section of river about 200 yards long , and I hope to have two wheels one each end . One will power the house and one the workshop and forge etc. I will then be able to use the saw bench , lathe , drill stand, sander,bandsaw etc in the woodwork shed , and a metalwork lathe , power hammer , drill stand etc in the forge/metalwork shed. I will also be able to mill wheat, crush/roll oats, barley etc and run any other old type static machinery I need , either direct or via line shafting and belts. Hope that gets your cogs turning !!!!!!lol... it will be suck it and see with me as I do it ....so more details as and when ...
cheers
Russ