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Hydroelectric - Pumping
micro hydroelectric and water pumping
So you want to make electricity or pump water from a water wheel... I get so many questions about this that It's time to share my limited knowledge. First let me say that I don't live in an area where I can design and test these ideas and products nor do I have a degree in electrical engineering but I have researched the web for several years now and found a few things of interest which you may find useful. I have also found a few that seemed too good to be true, none of which will be posted here.
There are sites where there are pullies for your gearing, blogs that cover chain gearing, and some very good articles on Spiral Pumps which can pump over 4000 gallons/day up 40'+ to your house, even ram pumps (with no moving parts) that can use 25' of head to pump water 300' up. It's all here. There are also a lot of sites from people who use water wheels to make electricity. The problem is that they tend to be home brewed jobs with little in the way of empirical testing and they tend to get their equipment (gearing, alternators) 2nd hand so what they develop usually can't be reproduced easily. Since I do not have a good hydro site I can't experiment myself to develop a "standardized" system.
The main thing to remember is that a water wheel turns slowly but a alternator requires higher rpms so you need a gearing system. Automotive type belt and pully systems, chain and sprocket, or gear reduction boxes will all work and can be found on these links or Ebay. Another thought is the alternator's resistance will increase as the load increases (your battery bank drains) so it will slow the wheel down. It's a matter of balancing out your alternator's power needs with your wheel's power potential (some formulas to help you are included too). A car's alternator is a poor choice, you need a low rpm alternator and there are some links here. Also the faster a wheel turns the more power it can potentially generate with less gearing but a water wheel @ 30+ rpm looks like a fan and slings water everywhere so you need to consider if the wheel needs to look beautiful (at say 10-12 rpm) or do you just want the power.
I have visited all of these sites and they all have passed my McAfee virus check so to the best of my knowledge they are all safe sites. There are so many sites out there that I'm limiting the ones here to the ones I found most useful.
Finally let me say that I'm not the expert here, the guys who actually build these systems know what works and what doesn't. If you've built a water wheel driven hydroelectric system and can provide detailed information on it let me know so I can include it here. Spencer
A man's trial and error process to make a water wheel produce electricity in blog form. He didn't research things well before he started so we learn a lot from his mistakes. http://www.navitron.org.uk/forum/index.php/topic,3097.75.html
A "catch all" paper covering everything from site evaluation, wheel construction, pumping, electricity... a little bit about everything. http://www.cd3wd.com/CD3WD_40/VITA/WTRWHLOS/EN/WTRWHLOS.HTM
Lessons learned by a student trying to use a car altenator for power generation in Nepal. Page forward in this page to see the entire story but this page has the info you need summed up. http://www.nathaneagle.com/ghatta
A good site for Spiral water Pump design with empirical testing http://lurkertech.com/water//pump/tailer/
Several Spiral water Pump articles http://lurkertech.com/water//
Spiral water Pumps http://www.wildwaterpower.com/
There are a lot of spiral pump videos on Utube.com here is one. http://www.youtube.com/watch?v=LWedIS5teJI&NR=1
Ram pumps can pump water several hundred feet up with no outside power source, reliable and rarely if ever need repair but they do require more head than most people have. You can google "ram pump" and find plenty of sites. Here is a good one. http://www.clemson.edu/irrig/equip/ram.htm
Pullies for gearing http://www.emotorstore.com/subCategory.asp_Q_catID_E_17_A_Sheaves_and_Pulleys_E_Sheaves_and_Pulleys
50-1 "speed up" gearboxes out of China made for power production http://www.alibaba.com/product-gs/51443201/Speed_Increasing_Gear.html
Reduction Boxes Remember that the input shaft will become the output shaft when assessing hp ratings since the box will be used to speed things up rather than slow things down. http://www.daltonbearing.com/supplier-catalog.asp?sid=195
The low RPM alternator I'd try 1st http://www.windbluepower.com/Permanent_Magnet_Alternator_Wind_Blue_Low_Wind_p/dc-540.htm
Low RPM Alternators http://www.windstreampower.com/Permanent_Magnet_DC_Generators.php
More alternaters http://www.hydrogenappliances.com/powerpmas.html
A well designed overshot water wheel is 80-85% efficient. The gearing needed to speed things up to run the alternator will eat up about 25-35% of the power. Here is a formula using metric conversions to calculate power potential for your wheel @ 60% total efficiency so it may be a little optimistic. http://www.reuk.co.uk/Calculation-of-Hydro-Power.htm
Yes, I do have articles and University papers on water wheel design and use this information in designing my waterwheels but I'm not including them here. And no; there is no such thing as a water wheel that can power a pump which wil supply its own water with no outside energy source. That would be a perpetual motion machine and those don’t exist so please don’t ask. I get this question about once a month. If in doubt consider friction.
My dream would be to live where I had an abundance of water with good head so I could build a testing station for low head (less than 12') applications. It would have the ability to control the flow and the head allowing me to develop gearing systems for different applications. But until I win the lottery these articles are the best that I can do. I hope they are helpful. Spencer
since 2/8/09
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