Home-made Water Power Thursday, April 21, 2011 9:15 AM
Home-Made Water Power For the Homesteader Submitted By Wesley Dalton
Water Power Large scale hydroelectric power has been used worldwide for a long time to generate huge amounts of power from water stored behind massive dams. Small scale hydropower has been used for hundreds of years for manufacturing, including milling grain, sawing logs and manufacturing cloth. However, it can also be used without a dam to generate electricity for home scale remote power systems. These so-called micro-hydro installations can be a very good complement to a solar power system, as they produce electricity 24 hours a day. Waterwheels--It's important to differentiate between water wheels and water turbines. A water wheel is more akin the antique version we are all familiar with--a massive wooden wheel that slowly turns as the creek pours down over it. Water wheels spin slowly, but with lots of torque. They are also surprisingly efficient!
This is my homebrew hydro plant, using a Banki Turbine design built from scratch. The generator is a homebuilt permanent magnet alternator. In a Banki design, the water hits the vanes twice, once upon entrance and then again upon exit. There is only about 3 feet of head available at the site, and the system is producing about 2 amps at 12VDC, fed by a 4 inch pipe.
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A while back, one of our neighbors constructed a water wheel generator using a squirrel cage fan, belt, pulley and surplus tape drive motor that produced a steady 1-2 amps of power, 24 hours a day. He used a natural dam (a log that fell across the creek years ago) to get the fall and to mount the generator on. Click here for more information on this clever water wheel.
Some General Micro Hydro Power Information Turbines--All of the commercial micro hydro generators available today use a small turbine connected to an electrical generator or alternator. Water is collected in an intake pipe upstream, travels down to the turbine in plastic pipe, and is forced through one or more nozzles by its own gravity pressure. No dam is needed; systems without a dam are called "run of river" systems. Power is generated by a generator or alternator directly connected to the turbine wheel (no gears or pulleys needed). All of the factors below must be calculated correctly for your micro-hydro equipment to make power most efficiently. All commercial micro-hydro setups are custom-made by the manufacturer for your specific application. For proper operation, you must supply the manufacturer with specific data about your site, most importantly the vertical drop in feet (called "head"), the amount of water flow available during different seasons in gallons per minute, and the length of pipeline required to get a sufficient head. In general, for a water turbine you need at least 3 feet of fall and at least 20 gallons per minute of flow. If you have more fall (head), less water is required. You can calculate potential head with a water level, a contractor's level and stadia rod, or with just a string level attached to a measuring stick. The more fall and flow that you have, the more potential power you can generate. You can measure flow by building a weir in the creek and measuring how fast it will fill up a 5 gallon bucket. Your pipeline must be of a big enough diameter to minimize friction loss in the pipe. Your micro-hydro supplier can give you specific information regarding this. Nozzle size and turbine wheel type are all interrelated to your total head and flow. Again, your hydro supplier will customize these for your specific application. Often, different size nozzles are designed to be switched in and out as stream conditions change throughout the year. There are two main types of turbines, impulse and reaction. With impulse turbines, a jet of water is created by the nozzle and squirted onto the wheel. Reaction turbines are more akin to propellor that spins INSIDE the pipe, generating power. The 3 primary impulse turbine wheel types are Pelton, Turgo, and Cross-flow. Pelton wheels are used in low flow, high head conditions, and Cross-flow wheels are for high flow, low head installations. Turgo wheels are somewhere in the middle. Francis and propellor turbines are the most common reaction type; the Francis design is very similar to the innards of a centrifugal pump. A Kaplan turbine is also similar to this design. Home built reaction turbines have been built using centrifugal pumps running in reverse (generating power with moving water instead of using power to move the water). -----------------------------------------------------------------------------------
Simple Home Built Waterwheel This machine was built by a neighbor of ours in about 2 hours, 6 years ago. It's been in constant operation since, except when the creek is frozen. He chose a natural dam, which was created when a tree blew across the creek. The tree is approx. 20" diameter.
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A slot was cut in the tree to channel the water into the turbine. The turbine was made from a junk squirrel cage fan. The fan housing was bolted to the tree, so that the water poured into the "output" of the fan, and came out a hole which was cut in the bottom of the fan housing, making for an "undershot" waterwheel. He used the pulley which was already on the fan, and belted it to a surplus computer tape drive motor (the kind they used to use in large computer tape drives, check our Products page for availability). The gear ratio is 1:3-the generator turning 3 times faster than the water wheel. They make excellent low rpm generators. This system charges 2 amps into a 12 volt battery, 24 hours per day! His only power needs were 2 lights, and a small car stereo, the water wheel provided more than enough. It doesn't work after the creek freezes(4-5 months of the year), and he simply lets it freeze over each year, without any apparent damage. It's easy power, cost next to nothing to build, and is low maintenance. The front bearing has failed twice (once every 3 years), but no effort was made to keep water out of the bearing-doing so might fix this problem. 2 amps may not seem like much, but consider the cost of solar panels required to produce 576 watt hours per day! Simple improvements could certainly be made to make a machine like this much more efficient. It uses a normal V belt, which introduces a lot of friction and loss. I don't know for sure, by my guess is the V belt may suck more than half the available power here. Gears, or a smaller belt would be interesting. I don't believe he ever took the time to try different pulley combinations either, it's possible there is room for improvement. Since we have been experimenting with them, it seems like a homebuilt wooden alternator or induction motor converted to an alternator (see our experiments page for more information) would work more efficiently by charging at lower rpm. Considering all the room for improvements, it's reasonable to think a unit like this could provide twice or three times the power. 50 watts, 24 hours per day would be an incredible amount of power considering the cost, low maintenance, and only about 20" of head on a small creek. Other simple undershot waterwheels have been made using 55 gallon metal or plastic drums with attached vanes, suspended above a river. Please let FCIV know about your experiences with home built hydro power!
Submitted By Wesley Dalton Wes Dalton lives and farms and tinkers on his family homestead in Floyd County. Wes attended The University of Tennessee but dropped out in his senior year because "I was bored to tears and wanted to get into real life". Inserted from
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micro-hydro power bucket
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Hello Hackers! For a long time I have been fascinated by the thoughts of free and renewable energy. My inspiration to build this device came from a cabin in the woods which was surrounded by tall trees which blocked out the sun and the wind. This left me unable to put up solar panels or a wind generator. There is however a small creek which runs on the property. My online research let me to some work in Guatemala by Sam Redfield. Sam built a very similar device for a small community which was isolated from power. Sam’s work was featured on MAKE and Gizmodo in 2008. The power generator in the system is a Permanent Magnet Alternator (PMA) with a pelton wheel directly attached to the shaft. Water is sent through four jets which strike the wheel causing it to rotate. The bucket and lid components were initially assembled at the Vancouver Hackspace. The first version of the bucket lid had the water distribution system assembled from 1 inch PVC parts. After on-site tests failed, I found that this system was too inefficient to distribute the high-pressure water needed to spin the pelton wheel. Version 2.0 of the water distribution system was more successful. Version 2.0 consists of a manifold which evenly distributes the water between the four 1 inch pipes. Parts List: Permanent Magnet Alternator (PMA) DC-540 – $229 A/C kit for PMA – $29 circular rubber gasket – $3.99 5 gallon bucket with lid grinder disc 45 degree PVC elbows marine goop epoxy various nuts, bolts and screws 200 feet of 2 inch water line – $350 2 inch valve – $19.79 2 inch pipe connectors – $ 2.86 2 inch to 3 inch rubber connector – $11.69 short section of 3 inch pipe – $1 3 inch pipe cap – $4.76 4 one inch plugs – $8.24 30 feet of 1 inch water pipe – $18 1 inch to 1/2 inch connectors – $4.28 small bits of wood – $1 various hose clamps – $5 zap straps – $1 approximate total cost: $750 Power output measurements: valve 1/2 open: 25.6V valve fully open: 56V The power bucket uses approximately 1.7 liters per second of water at full power. On my next visit to the cabin I plan to bring a dummy load and a second multimeter so I can measure the current produced by the system. Thanks to nefis from the Make magazine blog for his comments: power output There’s an output chart for the DC-540 on the Windblue website. A voltage output of 56V corresponds to the alternator spinning at 625 RPM producing 10 amps, generating approx 560 Watts of power. http://www.windbluepower.com/Permanent_Magnet_Alternator_Wind_Blue_Low_Wind_p/dc-540.htm and specifically this chart Planned future improvements: The creek runs slowly in the summer time which means that I can not run the system at full power without draining the reservoir. My plan to overcome this issue is to ‘pulse’ the system by using some sort of water level sensor in the reservoir. When the reservoir is full the system would automatically open the valve, then as the reservoir is nearing empty the valve would automatically close. My biggest hurdle in getting this modification to work is finding or building a controllable 2 inch valve. Assembly tips: Drill holes in the bucket lid to accommodate the shaft and two mounting posts of the PMA. The circular rubber gasket is placed between the PMA and bucket lid around the shaft. Apply copious amounts of marine goop around the bolts on the bottom of the lid to stop water from splashing up on the PMA. The pelton wheel is constructed from an 8 inch grinder disc with 12 ‘spoons’ mounted around the circumference. The spoons are made by cutting the 45 degree PVC elbows in half. Holes are drilled in the grinder disc and the cut elbows are mounted using nuts and bolts. Marine goop is applied to the fasteners to stop them from coming undone. The water jets are mounted to the bucket via the wood ‘jet aimers’, for lack of a better name. Holes are drilled in the sides and the bottom of the bucket to allow it to drain. Assembly images:
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pelton wheel
valve and manifold
pvc elbow
drilling the grinder disc
partially assembled pelton wheel
open valve
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drilling manifold
1 inch adapter
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SheepLord October 7th, 2010 at 03:12 You mentioned that you were thinking of a way to pulse water through from the reservoir. A thought that comes to be would be a bucket connected via a pulley to a hinged lid over the main outlet. A spillway at the top of the reservoir will fill the bucket when the reservoir is topped off. The now heavy bucket will pull the lid of the outlet to the open position. Once open, the reservoir will drain, as it is doing so it will quickly fall below the level that allows water to go out the spill way so no more water will fill the bucket. The bucket has a small hole in its bottom that will let water drain out slowly. As it empties it will at some point lighten enough so that the lid to the outlet will tip back sealing the outlet. The bucket will continue to drain and the reservoir will start to refill. Adjusting the rate that water escapes the bucket so that it hits the close off point about when the reservoir is drained should be a matter of either drilling a larger hole or drilling more. Closing holes will adjust in the other direction. The outlet lid might also need a little bit of weight on it to help it seal snugly until the water pressure of the reservoir kicks in. The deeper the reservoir, the bigger the bucket will have to be to overcome the pressure that the water will exert on the outlet cap when the reservoir is full. Good Luck. SheepLord October 7th, 2010 at 03:30 Actually an even simplier way occured to me that makes use of a siphon. Have your pipe enter the resevoir through the wall of the resevoir several inches below the top. Then have it make a 90 degree turn to the bottom of the reservoir where it will end just above the bottom. The reservoir will fill until the water level is above the point where your pipe enters. A siphon will be completed at this point and the pipe should start drawing off water very quickly, draining the reservoir. Once it starts sucking air the siphon will stop and the reservoir will start filling. One problem would be in situations where the water flow coming in is a trickle that will just spill over the crest inside the pipe and never completely fill the pipe and forming the siphon. I have a feeling that there is a solution for this in the world of toilet pluming or ancient irrigation. Good Luck (again). dwmizell October 11th, 2010 at 23:33 Perhaps a valve based on the ‘flapper valve’ from a toilet would be a simple solution. Great work and Good Luck! Ameridan October 15th, 2010 at 15:24 I posted a thread here on this: http://www.godlikeproductions.com/forum1/message1222443/pg1 Perhaps you would like to view/participate The Tiny Life , Archive » Micro-Hydro Power Bucket November 17th, 2010 at 05:30 [...] Via Share!: [...] Sam Redfield November 21st, 2010 at 15:57 NIce job Paul! A build manual for my generator is now available at the AIDG website if you are interested. Curious how much head you had at your site, and if you had made any improvements since you posted this video. Nice to see people making the generator! Marx Riv January 11th, 2011 at 03:35 Awesome job! Has there been any updates to your video, instructions or parts list? Zulema Beauchesne January 21st, 2011 at 16:39 I don’t think people realize just how important alternative energy and solar energy in particular is. Just wanted to say thanks for posting this. an akist March 10th, 2011 at 06:54 Why not use a marine float switch? Search on westmarine.com (big chain store) for ‘float switch’ and a lot of options come up.
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Looks great, I wish I could put a reservoir on my creek, but fish and game would not like any modification of the waterway , even if I could demonstrate that it wasn’t hurting the creek or marine life. Can you make a drive pipe for this, as is used for ram pumps? http://www.riferam.com/rams/raminforeq.html http://www.youtube.com/watch?v=yHqDkd7KdPg Or perhaps the water pressure just wouldn’t be good enough for 50 volts, but it could put out 6? 12? Thanks! backiss Inserted from
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