7- water wheel :
Pond Water Wheel Systems – More than just Decor?
courtesy to : pondinformer.com/best-pond-water-wheel/
Historically, water wheels have been used since ancient times as a method to convert the energy of flowing water to different forms if power, often as watermills. Wooden wheels are comprised of a large wheel with a number of blades, steps, or buckets which are used to collect water and power the rotation of the machine. In the UK and US, waterwheels are commonly mounted vertically on a horizontal axis (pictured), but can also be constructed on a vertical axis with the wheel horizontal. In regards to power generation, the energy of water is transmitted through a special axle or gear located in the center of the wheel, which is then converted into electricity via a generator.
Classic wooden waterwheel design, powered by a “backshot” water flow which comes from an outlet on top.
Although they have been used as power generators for centuries, they have mostly been replaced in modern times by the vastly more efficient water turbine. Due to this, many waterwheels, especially in ponds, are now designed mainly as decorative items which help bring a water garden to life. As well as looking fantastic as decorations, a moving water wheel will also provide other benefits, such as increased aeration and oxygenation. The continued movement of the wheel against the water will create more flow and provide additional nutrients and oxygen across the pond system.
Water wheels can still technically be used in ponds to power electrical equipment, such as low-wattage pumps, but there are downsides, such as their dependence on constantly flowing water and need for frequent maintenance (i.e., bearing replacement). Other eco-power methods, such as solar power and wind power, are more reliable for general power generation, and we’d usually recommend these over water power for regular pond owners. With that said, waterwheels are some of the best pond decor around, and still have a few extra benefits which make them great choices for fish ponds:
Benefits of Pond Water Wheels:
1) Provides Aeration & Oxygenation
The movement from water wheels helps distribute extra nutrients and oxygen across the pond system, which can be very beneficial if you have koi and goldfish in your pond. The added aeration will also improve filtration as beneficial bacteria have more dissolved oxygen to help break down harmful substances in water.
2) Deters Pests & Algae Growth
Many biting insects, such as mosquitoes, love to lay their eggs in slow-moving water, and a water wheel can help prevent that by causing surface disturbance. As well as this, algae thrive in stagnant conditions, and the extra aeration from a wheel can keep algae growth lower in summer months if other water parameters are well maintained (see water quality).
3) Looks Great as Decor!
Finally, water wheels are a big part of modern history, and look simply fantastic as decorations in water gardens and fish ponds. They’re also becoming something of a lost art, so having one in your garden is a great homage to a machine which redefined the industrial world.
How do Pond Water Wheels work? (Best Types for Ponds)
Although there are many different types of waterwheels, most common wheels in western Europe and America make use of a vertical wheel with a horizontal axis (pictured). All of these wheels are powered by water flow, with the difference being how the water is passed through the wheel to create movement.
Diameter: 15 inches (38 cm)
Type: Overshot Wheel (requires overhead flow)
Material: Wood (Pine)
Coasting: Non-toxic Soy Bean Resin
Bearings/Shaft: Included (10″ Shaft – 5/8″ Axle)
Support Frame: Not Included
Flow Rate Requirements: 50-200 GPH approx
Waterwheel diagram showing an “overshot” design where water flows over the top of the wheel blades.
In terms of pond water wheels, the most common types are undershot waterwheels and overshot waterwheels. There are many more sub-types, but these two designs are usually better for smaller water gardens as they’re more efficient with lower water flow, as well as being easier to set up!
1) Undershot wheels are some of the oldest designs, with waterwheel blades usually being very flat compared to the “buckets” of overshot wheels. These waterwheels work with the natural current of your pond, with the flat blades being dragged into movement by the water underneath. They’re best placed in an area of strong water flow, such as in front of a large waterfall or in-line with a dedicated pond pump. Although they’re great as décor due to their easier installation process (requiring no overhead water flow), they’re one of the least efficient in design, so not a good choice if you want plenty of movement from a low flow rate pump.
2) Overshot wheels are another common type of pond waterwheel design, being more efficient than undershot but more difficult to install and get moving. These wheels can achieve up to an 80% efficiency with specialist design, but the height of the wheel and diameter of the blades are directly proportional to power generation. This means you often need to go BIG to achieve decent power generation, making them sometimes non-practical compared to other eco-power methods. For decorative purposes, overshot wheels can look great and will have plenty of movement if installed with a quality pump with decent flow rate and head height values. Most water wheel kits will be an overshot type as they’re easier to keep moving when the water framework is installed correctly.
Water Wheel Powered Pond Pumps – What Should you Choose?
Submersible pumps are great choices for undershot water wheels as they can be placed directly in-line with the wheels blades, which also provides you extra flexibility in terms of placement. The pump doesn’t need large head heights as an undershot design is powered via water flow, so the pump will simply need sufficient gallon per hour (GPH) turnover to get the wheel turning. If you’re using a smaller water wheel you could even make use of a solar powered pump model which should be sufficient in powering the wheel in both spring and summer months. This is also a great way to save money as solar power doesn’t add to your monthly electricity bill!
Submersible ponds are placed underwater, making them convenient for “undershot” wheels, but can also easily power “overshot” designs, too.
For overshot designs, or very tall water wheels, solar powered pond pumps may not be suitable as you’ll need to lift water to the top of the water wheel. In this instance a quality submersible pump or an external pump would be a better choice, as both would provide higher head height values compared to solar powered pumps. To work out exactly what size pump you need will depend on the height of the waterwheel and how much flow is required to turn the blades and create movement. For example, for a 1 foot wheel which requires 200 GPH of water flow, you’d need a pump which can provide at least 200 GPH of water pressure at 1 foot of head height. An external pump model in this instance would likely be overkill, with a small submersible (pictured) being more cost effective. However, for a 5 foot water wheel which benefits from 500+ GPH of water pressure, a small external pump may be more energy efficiency in the long term.
In most cases, and with the water wheels reviewed in this article, smaller submersible pumps and solar pumps would be more than sufficient to get the wheels turning. For water wheels around 15-25″ in diameter, even a garden hose would suffice in creating movement; especially in overshot “bucket” designs!
Pond Waterwheels – Common Questions Answered
Q) DIY wheel or purchase a water wheel kit?
If you have the DIY know-how or the determination to take on such a project, constructing a water wheel for your pond can be both fun and rewarding. The designs of wooden wheels have been refined over the years, but the basic construction remains fairly similar – consisting of the wooden wheel, blades, support, and metal axis and bearings. If you’ve never created a wheel before, we recommend U-BILD’s step-by-step book which details each part of the process in clear diagrams. The same techniques outlined in the book can be applied to much larger (or smaller) water wheels, so it’s a useful resource for all types of design.
The drawbacks of creating your own water wheel is the large time investment involved and lower efficiency in comparison to specialist designs. Purchasing a pre-made wheel or kit from a dedicated seller will ensure you have a optimized wheel fit for purpose, and most even come with lengthy warranty periods in case of problems. If you’d like to still do some DIY, many manufacturers sell the wheels and support frames separately, so you can always purchase just the wheel and construct the much easier framework yourself. If you just want a wheel that looks great, moves well, and are not interested in constructing things yourself, save the hassle and pick up a waterwheel kit!
Q) Can a water wheel run without a dedicated pump?
If you already have a pond pump powering a waterfall or filter system, and the pump is providing plenty of flow, an undershot type water wheel can sometimes be installed in-line with the existing pump. Although we recommend dedicated pumps for larger wheels, if you’re purchasing a smaller design, you can install the wheel in front of the strongest flow in the pond and see what happens! Many manufacturers who specialise in wooden waterwheels optimize their designs for low water flow conditions, and not electricity production, so you’ll often find your wheel starts turning even with minimal currents.
For much larger water wheels or water wheels designed for overshot water flow, a dedicated pump is usually best to ensure you’re getting sufficient flow at the correct water head heights. You can either design or purchase a wooden framework to install the water spout on, or make use of rigid pipework to achieve the desired height on a budget.
Q) Are water wheels safe for koi and goldfish?
Water wheels are generally safe for fish, and can actually be beneficial as they provide extra oxygenation and aeration to pond waters. The major problem with water wheels, especially undershot designs, is their depth placement in the pond. If the water wheel is placed too close to the pond floor and are not elevated enough, fish may become stuck in the blades as they pass the liner. Both goldfish and koi are curious creatures, and will enjoy spending time around the base of the wheel due to the higher dissolved oxygen conditions. To keep fish safe, the wheel needs to be installed in an elevated position, and the wheel material needs to be treated with a non-toxic coating so it doesn’t leech into water. If you’re constructing the wheel yourself you’ll have full control over the materials and coating used, however, if you purchase from a manufacturer you’ll want to double check the water wheel is suitable for ponds with fish. The wood coating should be natural (i.e., soybean oil) and the bearings should contain no harmful oils or crude mixes which can easily damage the eco-system.
Finally, NEVER use oil on your water wheel bearings as this can pollutant your pond and harm fish. Always replace bearings outright by contacting the manufacturer or purchasing replacements with non-toxic coatings. They should be replaced every few years as metal bearings will inevitably rust while in contact with constant moisture.
The Best Pond Water Wheel Kit Reviews 2018
Below are some of our top water wheel recommendations, all of which have been chosen based on their build quality, non-toxic materials, and costs. Included is both basic wheels and water wheel kits, with all being good options for both decorative purposes and as water features.
Best Small Pond Water Wheel
Wooden water wheels need to be treated with a non-toxic coating, such as soybean extract.
For the budget consensus or for smaller sized water gardens as decor, Practical Garden Pond’s 15″ diameter wooden water wheel is a great choice of entry-level wheel. Hand-crafted from high quality pine wood, the wheel features a 15 inch (38 cm) diameter design with a popular overshot movement type. Unlike undershoot wheels, this wheel requires water flow coming from overhead for the best operation. Water which hits the wheel will be collected in the blades, and the wheel will turn on it’s 10″ shaft and 5/8″ axle as water builds to the correct capacity.
To achieve a good flow rate and decent movement on the water wheel we would personally recommend a pump ranging from 50-200 GPH. This is a small sized water wheel and will not require a large amount of flow to start turning, and too much water will simply overflow over the sides. The height of the wheel is minimal, so most pond pumps (even solar power) should have sufficient head height for optimal flow regardless of model. You can even try using your garden hose!
Although no support frame is included, the water wheel is very small so creating or purchasing a separate support should be quite easy. The wheel turns on its axle via the bearings in the wheel, so a pole can be inserted through the axle or it can be mounted in clamps or brackets over the pond. The wheel works best as decoration, either moving or static (no water), and is not suitable for energy production due to its small-form factor.
Finally, the wheel is safe for fish ponds and wildlife ponds thanks to it’s oil-free bearings and natural soybean wood coating. The coating is made from soy bean paste and actively fills the pores of the wood to prevent moisture getting inside. Overall, a great little water wheel which would be perfect as decoration in a small water garden or small goldfish pond.
Best Large Pond Water Wheel
If you’re looking for a larger water wheel with more of a “wow” factor, these Amish-made wooden wheels from Backyard Crafts are some of the best around! With wheel diameter sizes ranging from 15 inches, 30 inches, 36 inches, and 48 inches, they also have a water wheel for all sizes of ponds.
The wheels are crafted by an expert Amish craftsman specialising in decorative water wheels, and are available in a range of impressive colors. The colors used are natural and non-toxic, with the pine wood material also coated in natural soy bean extract to keep moisture from damaging the wood. Both coating and colors are 100% safe for fish and wildlife.
The wheels are all overshot designs, so will require water flow to enter from the top of the wheel for best operation. The smallest wheels (15″) can be powered easily with solar pumps, small submersible pumps, or even a garden hose. The large wheels, such as the 48″ wheel, would require a stronger pump which can maintain higher water pressures at up to 1 foot of head height (height of water wheel). Although these are approximate values, we’d recommend a pump ranging from 400-600 GPH for the largest wheels to ensure smooth movement and the best aesthetic.
The bearings are sealed and zinc-plated for durability and should not be oiled or greased, as this is dangerous to the ponds eco-system. Although the bearings have a long lifespan, replacing the bearings every few years when movement is slowed is good practice. The wheels rotate on a stationary cold-steel axle, and can be mounted with your own poles or brackets. There is no support frame included, so you would need to mount the wheel and configure pipework separately.
Overall, a fantastic range of hand crafted water wheels with options for both small and large water gardens. A great choice if you want a durable wheel which will function for years without trouble!
Diameter: 15 inches (38 cm) – 48 inches (123 cm)
Type: Overshot Wheel (requires overhead flow)
Material: Wood (Pine)
Coasting: Non-toxic Soy Bean Resin
Bearings/Shaft: Included (13″ Shaft – 5/8″ Axle)
Support Frame: Not Included
Flow Rate Requirements: 50-600 GPH approx (depending on diameter)
Best Pre-Built Water Wheel Kit :
3) Amish-Made Gristmills Water Wheel Kit Review
For pond owners who dislike the thought of putting together their own framework and just want a great looking water feature! This second water wheel entry from Backyard Crafts is a pre-built and fully functional water wheel straight out of the box, coming with both the support frame and pump to get the wheels turning.
The water wheel is housed within a very pretty wooden frame made to resemble a traditional watermill. The wheel sits with it’s axle within the main house which extends to the top of the wheel and moves water from the top to bottom in an “overshot” design. Although the wheel is designed for exterior use, coming with it’s own water tray, it can still be placed on a shallow pond shelf or on an embankment next to the pond.
The windmill kit comes in two sizes; one with a 15 inch diameter wheel and the larger being a 30 inch diameter wheel. Both are hand-crafted with yellow pine wood and treated with a non-toxic fish safe soy bean resin. The bearings are also oil-free, so the wheel is 100% safe for fish, plants, and wildlife. Like other water wheels, the metal bearings will eventually fatigue and should be replaced every 2-3 years and should never be greased with harmful oil.
Although you’ll receive everything you need to get the water wheel functional, there is still some assembly required for the 30″ model which will require a drill with a square bit to put together screws into the watermill and bottom tray. A half-inch wrench is also needed to tighten the nut which is attached to the axle before operation. A small submersible pump is included for convenience and has been fitted to easily power the wheel by pumping water to a small outlet in the head of the watermill. The pump will require electricity to work (6″ length cable), so you would need to make sure you have a power outlet handy to get things running.
Overall, a great hassle-free water wheel kit crafted from high quality wood, non-toxic materials, and with the addition of a water pump ready for operation. Although you have less flexibility in terms of design, the water wheel is a good choice if you just want a fancy decoration without the added fuss of construction.
Diameter: 15 inches (38 cm) – 30 inches (76 cm)
Type: Overshot Wheel (pump included)
Material: Wood (Pine)
Coasting: Non-toxic Soy Bean Resin
Bearings/Shaft: Included (pre-built)
Support Frame: Included (pre-built)
Flow Rate Requirements: 300-500 GPH approx (pump included)
Waterwheel DIY :
courtesy to : www.runnerduck.com/garys_waterwheel/garys_waterwheel.htm
See Scott Winegar's comments from when he built this waterwheel at the bottom of Gary's instructions.
This waterwheel comes to us from Gary Mastolier in Bonners Ferry, Idaho. We love it when people share their woodworking plans with us and Gary did a wonderful job on this waterwheel.
Here's what Gary wrote:
I was very interested in your water wheel project.
Here is the water wheel I built earlier this summer. Some of my construction techniques are quite similar to yours. I will be building our water feature and adding the waterwheel to it next summer.
Bonners Ferry, Idaho
It is made from mostly cedar except for the side cheeks which are Doug fir. It is 36 inches in diameter and the 16 buckets are 12 inches wide.
The pattern I saved of one of the face cheeks.
Routed and ready for assembly.
The face cheeks were all put together using biscuit joinery and Titebond III glue. You are right, the cutting of these has to be very precise.
I made pillow blocks from wood which seem to work just fine. That's two pieces of 3/4" Doug fir glued together cross grain to each other.
The only metal in this project other than a few screws are the axle, two roller bearings and the metal flanges to hold the bearings centered in the wooden pillow blocks.
The two outer hubs are two pieces of cedar laminated together at cross grain to each other. Ditto for the larger inner hubs.
I burned the cedar with a propane torch to bring out the grain and give it contrast. The entire wheel is coated with three coats of hot linseed oil. This was a fun project. The next one will be six feet in diameter.
This is a Sketchup rendition of approximately what our water feature will look like. The waterwheel will be raised higher than shown and will drain into a cascading waterfall. The filter system and pump will be housed inside the building for ease of access.
I just got the 10X20 foot "Garden shed/Grist mill" done in time to button it up for winter. Siding, windows and door as well as the pond for our water feature will have to wait until next summer.
That's about it. We hope you liked this project. Thanks a million Gary for sharing this wonderful waterwheel. We look forward to a picture of the finished pond.
If you build it and your friends ask where you got such a clever idea, please tell them that you got it at RunnerDuck.com.
Scott Winegar's comments from when he built this waterwheel.
I used Gary's plan to make my own water wheel. I had some pieces of cumaru left from a deck project. Although they were only 5.5 in wide, Gary's plan worked fine.
My wheel is 12" wide, and I laminated pieces to form the "buckets."
I joined them with a waterproof polypropylene glue, and I used my Festool domino jointer. I was concerned that the standard biscuits would rot out, so I made biscuits from scraps of cumaru.
Gary's plan for an exoskeleton made great sense, so I use 5/4 x 4 cumaru to do what Gary did.
I joined the exoskeleton with stainless pocket screws, and joined the exoskeleton to the "buckets" with stainless screws from the inside. Cumaru will eat up any metal except stainless so I threaded in some 1" x 1/2" stainless plumbing bushings for the pivot shaft.
The wheel will be used to run a piston style pump on a crank and a spiral pump mounted to the side of the wheel. It is for decoration only, and not actual work, but it looks great.
I wanted to thank Gary for sharing his design, rather than charging a bunch of money like everyone else does.
Building a Waterwheel :
courtesy to : www.reuk.co.uk/wordpress/hydro/building-a-waterwheel/
If you are fortunate enough to have a stream running through your land then you are blessed with a source of clean green renewable energy. In this article we will follow the construction of a complete DIY waterwheel power generation system.
Pete from Mawdesley in West Lancashire is an electronics engineer with good hands on ability with anything mechanical. With an interest in self-sufficiency, and a property with a stream running through it, the only logical thing to do was to build a waterwheel to generate electricity for his home office.
The stream crossing Pete’s property has a total head of 1.5 metres. However, to protect the neighbours from the noise of a waterwheel, there is 0.5 metres of usable head. He has estimated flow rates at just 1-2 litres per second (l/s) in the summer, 40-60 l/s in the autumn/winter/spring typically, and a whopping 200-1000 l/s when the stream is in flood after heavy rain.
Damming the Stream :
First of all a dam had to be constructed in order to funnel the stream toward the waterwheel. (Where damming is not possible, a Run of River set up would have been used.) The dam created a 24 incheshead of water which passed through a gap equal in width to that planned for the waterwheel paddles – 2 feet.
During construction of the dam, two submersible pumps were used to divert water around a temporary ‘mud‘ dam with a sump hole in the front. The dam was built during the summer when the flow rate was at its lowest, and so the pumps were only on 5% of the time during the 24 hour period required to get everything built.
Constructing the Waterwheel
The waterwheel itself was constructed from 12mm marine plywood which typically comes in 8ft x 4ft sheets. It was these dimensions which dictated the final diameter of the waterwheel (1.2m = 4 feet), and the width of the paddles (0.6m = 2 feet, i.e. the size obtained when a plywood sheet is cut in half). Just two sheetswere required for the complete waterwheel at a cost of around £30 per sheet.
The waterwheel is made up of 2 disks (the sides), and 12 paddles. Using 12 paddles makes it easy to mark out the location of each paddle on the wheel since they are separated by a 30 degree angle (= 360 degrees / 12). The paddles were chamfered to minimise the surface area of water hit by the wheel as it rotates, with the aim of making the waterwheel as quiet as possible in operation.
Even marine ply needs to be waterproofed if it is to last any length of time without rotting in water, so two coats of Thompsons Waterseal were used to seal the plywood. This was not really enough since the ply remains porous – so much so that when the water level drops and the waterwheel stops spinning, the bottom of the wheel absorbs water where it dips in the stream. The wheel then turns unevenly for a week or so due to the uneven weight distribution which greatly increases the wear on the bearings and is less efficient. That said, after one year of operation the plywood still looks as good as new.
Above is an image which shows how the paddles were fixed to the disk of the waterwheel. Screws were used to hold everything together, but nuts and bolts may have been better to reduce the chance of structural failure. To add strength to the whole waterwheel, 8mm metal rods were fitted underneath every paddle. With all the paddles screwed in place and everything sealed, the basic waterwheel looked like this:
The Framework :
Any waterwheel needs a framework supporting an axle on which it sits rotating freely as the flowing water pushes it around. Lengths of brand new kiln dried 3″ x 2″ oak were used (obtained for free, otherwise a less expensive timber would have been used). The finished frame was bolted into the bed rock with 6 inch long M8 bolts as shown below during construction:
This alternator reaches 12 Volts output at just 150 RPM, and will charge a 12 Volt battery at 15 Amps at 2000 RPM. The manufacturers claim that this unit can “handle over 10,000 RPM with ease“.
Since this waterwheel rotates at just 10 RPM, a roller chain and hardened sprockets were used to gear up the waterwheel output from 10 to 275 RPM (in stages of 1:4.5 and then 1:6 to give total gearing of around 1:25).
20mm bore pillow block self lube bearings (pictured below) were used for the axle (cost around £3.50 each from eBay UK – click here to search eBay for pillow block bearings).
Permanent Magnet Alternator
The permanent magnet alternator chosen for this project was the WindBlue DC-540 – an alternator typically used in low wind areas on wind turbines, but also well suited to hydro power applications (with suitable gearing). The alternator cost just over US$200 plus shipping to the UK (which took one month).
Smaller (12mm bore) pillow block bearings (pictured below – bearings are blue) were used to hold the sprockets in place.
Using the Power :
The WindBlue alternator comes with a built in bridge rectifier to turn the generated AC electricity into DC which can be used to charge batteries etc. Connections to the three phase AC output of the alternator are also provided so that an alternative (external) bridge rectifier can be used.
The 12 Volt battery bank consists of four 55Ah AGM deep cycle solar batteries connected in parallel for a total capacity of 220Ah at 12V. Currently 2.5mm equipment wire (multi-stranded copper) is used to connect the rectified DC output from the alternator to the battery bank 15 metres away. Since there is some voltage drop* through this relatively thin cable over the 15m run (a few percent), it will soon be replaced with thicker (10mm diameter) cable.
* Click here to try our automatic line losses calculator.
A Xantrex c35 controller (available from US$100+ new) is currently used as a charge controller to protect the batteries from overcharging. When the set battery full voltage is reached, the controller is configured to make an open circuitleaving the waterwheel (which then has no load on it) to free wheel. This could easily result in the waterwheel being damaged, and so a 12/24V resistive heater will soon be added as a dump load to be automatically turned on by the controller when the batteries are full.
The generated electricity is split between a battery in the garage and the main battery bank (pictured above) which is located in a garden office (converted shed). The charge is split through a diode and power resistor (5 x 0.1 Ohm 10 Watt rated connected in series) with 0.25-1.25A typically going into the garage battery, and 2A-6A into the office battery bank. (There is also a 65W PV solar panel fitted to the roof of the house to keep the main battery bank charged during the summer).
In the office a 600 Watt modified sine wave inverter provides 230 VAC to power a laptop and TFT display. The battery in the garage is connected to a 200W pure sine wave inverter to power lighting.
(note that a modified sine wave inverter cannot typically be used with energy efficient CFL light bulbs).
Future Improvements Planned
Since the alternator generates high voltages at low RPM it would be more efficient to reconfigure thebattery bank to 24V or even 48V. This would also reduce the thickness of cable required between the alternator and battery bank, but would necessitate the purchase of (more expensive) 24V or 48V power inverter.
More Waterwheel Information
We have more information about waterwheels available in the following articles:
Calculation of Hydro Power
Introduction to Waterwheels
Electricity from Waterwheels