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Homemade Wind Turbine & Tower
Roger Beale and his recently-deployed retirement project.

I grew tired of cranking up the old gas generator each time we lost power during winter outages. I said to myself, “I want to do something different—something simple, easy to maintain, something low-cost that I can handle by myself.” And now, five years into retirement, I have this 100-foot-tall monster standing in my backyard.

I started researching building a wind turbine on the Internet, and gathered as much information as I could. Two excellent resource books I recommend are A Wind Turbine Recipe Book by Hugh Piggott and Homebrew Wind Power by Dan Bartmann and Dan Fink.

Constructing the lattice tower was a time-consuming effort. I had to learn to weld and use a cutting torch. The tower is constructed from steel tubing (the top rails of chain-link fence). I located my tower carefully among the large trees in my backyard. I used the oak trees, a 6-ton pulley, and a 5/16-inch steel cable system—raising the tower using a second pulley connected at two different stress points along the tower with a 12-volt, 12,000-pound winch. An oak tree acts as a “gin pole” to raise the turbine; other trees help support the main tree (you can pull one over, trust me). I can push a button to raise and lower this homemade renewable energy system.

Anyone handy with tools and who has patience to learn can create a similar device, even if at a lesser height or capacity than this project. The turbine is just a simple homemade alternator, using a six-stud trailer-wheel hub with two bearings. With 32 rotating rare-earth magnets next to a three-phase fixed stator wound by hand with #10 copper coils, there’s really not that much to it. I like to keep things simple—I went with this design because it’s simple and it works. I’m always working on it, enhancing it, and making it better. I’ve seen it generate more than 3 kW at times. With a 1 kW solar-electric array, I’ve been pleased with the results—cutting about 30% off the old electric bill. 

This is a 48-volt hybrid (wind/solar) off-grid system with three parallel Magnum Energy inverters that feed a separate 150 A breaker panel in our home to provide standard 120/240 VAC electricity. The hybrid system charges 16 deep-cycle golf-cart batteries, which gives us at least 24 hours of backup with no wind or sun energy input.

The solar-electric array is eight 12 V, 130 W modules, with two groups of four in series to provide a 48 V output. The other four modules are configured in the same way. Both 48 V series strings are then connected in parallel to a 60 A Morningstar controller. The array is mounted on a large frame with 12-inch casters and tie-downs, so I can easily rotate it on the deck to maintain a higher level of performance, morning to sunset. 

The turbine and solar-electric modules maintain a good charge on the batteries. I use a Morningstar relay driver to monitor battery voltage and amperage, and it automatically switches if there’s wind or solar energy to be had. I also have the relay driver programmed to apply a dynamic braking relay (shorting out the three-phase alternator) if turbine blade overspeeding occurs (the battery voltage suddenly rises) or if the Morningstar diversion controller or load resistor fails.

I would have paid more than $25,000 to purchase such a system commercially. My project cost was between $5,000 and $7,000, including the batteries.

Roger Beale • Evington, Virginia

Comments (19)

Roger Beale's picture

Hello everyone,

I upgraded to the Schneider Electric Conext XW 6048

http://www.youtube.com/watch?v=PGQm...

Roger

Roger Beale's picture

Home Constructed Hybrid Wind/Solar Energy System http://www.homepower.com/sites/defa...

Michael Welch's picture

Beautiful photo, Roger.
Michael, HP magazine

Roger Beale's picture

Thanks Michael,
Lots of hours welding that tower together.
Roger

Roger Beale's picture

Hi Christopher,
I had to apply for a special use permit, I had to get approvals from the county planning commission and the board of supervisors. I was required to get an approval from a structural engineer (PE) and electrical inspections. About a three month process....before permitting. Being a retired systems engineer helps a little I think with the electrical. I found the county administration folks easy to work with. They were very helpful getting me thru the processes.
Roger

Christopher Vaught's picture

Hi Roger, Thank you for sharing your wonderful ideas and successes. I live in neighboring MD and am considering, and studying, for a similar set up. I was wondering what you had to go through in regards to permitting for a home designed and built turbine and tilting tower set up in VA.? I think in MD I would have to get everything approved and signed off for in biquadriplet, by both structural, mechanical, and electrical engineers, before even applying for any of the County or State permits.

Roger Beale's picture

Hello,
http://wind.jmu.edu/vwec/2013windfe...

We can talk "eyeball to eyeball" in Harrisonburg about your concerns & ideas you may have during your construction.

Tilt-down lattice tower and power winch.
Docking station for maintenance.
My 18 foot homemade rotor.
Furling tail
32 magnet 3KW 3 Phase Alternator.
Windturbine Electrical & Electronic controls
Davis Weather Instrument programming for emergency shutdowns.
Windturbine PWM diversion Control.
Midnite's Classic 150 Controller MPPT, allowing my blades to run more efficiently at higher speeds.
Outback's MPPT Solar Charge Controller.
My Magnum Energy Master/Slave Inverters.
Q&A

See you there March 16th.... Roger
http://wind.jmu.edu/vwec/2013windfe...

Kansas wind's picture

Hello from Kansas. I'm interested in construction of a new turbine. I have worn out two Southwest Windpower units in ten years and I need a beefier unit twith a kW output or so. The 40 mile per hour winds keep them furled most of the time and the bearings and blades just don't last. What blade set did you use and bearing system? I enjoyed your article.

Roger Beale's picture

I do wish I had your average wind speed… I have only about 6 mph average speed. I do have those days when it’s 12 – 15 mph and gusting to 30. I constructed my own blades and the bearings are the standard trailer 6-stud wheel hub and my magnetic rotors are completely homemade. If you’re having all that trouble, you need to slow everything down. Get your tool-bag and modify your tail, lowering the rotor/blade RPM by adjusting your furling so that the tail (completely) and absolutely furls the blades all the way out of the wind at a lower wind speed. Make the tail lighter and/or smaller so it furls sooner and completly. If you indeed furl all the way out of the wind, the blades must..and "will" slow down. If you run your wind turbine slower, it will last much longer. Don’t try to get that very last amp out of it. Make sure your diversion circuits are truly working correctly (when you’re not looking) and do keep the turbine loaded (and running slower). The larger wind turbines (rotor sizes) usually run at a slower rpm, and that may be what you need to do……..
Hope this helps,
Roger

Kansas wind's picture

Thank you for your reply. I am not sure what my average wind is. It must be high because I am within five miles of one of our
largest wind farm with 300 large wind machines. In the spring, summer, and fall there are days when the wind stays above 30 mph
and my machine stays completely furled for 36 hours and boy does it make a lot of noise with the wind blowing on the sides of the
blades. It spins really fast even when the electrical brake is on. Some clear, sunny days in the summer we get 45 mph gusts. The
machine has been tied down with a rope wrapped around the blades and tail just to keep it in one piece for the last 8 months. So
I guess what I need is shorter blades. Another thing would be a mechanical brake to totally stop the darn thing. My diversion circuits and big resistors are working fine and darn near hot enough to heat the whole house on windy days. One machine destroyed itself,
I'd like to keep the other one going.

Roger Beale's picture

Two excellent resource books I recommend are Homebrew Wind Power by Dan Bartmann and Dan Fink at http://www.otherpower.com/. Also A Wind Turbine Recipe Book by Hugh Piggott at http://www.scoraigwind.co.uk/. I really received a lot of valuable information from them over the years...

Ian Woofenden with years of experience on wind turbines may also have an idea or solution for too much wind..........

Roger

Scott Russell's picture

Hey, Kansas. To your point about keeping the other one going (and in case you haven't already come across these articles on the site), you might read through the following. There may be some useful bits...
https://homepower.com/articles/trou...
https://homepower.com/articles/wind...

Wildshot's picture

Roger, which morningstar relay and dynamic braking relay are u using?

Roger Beale's picture

My hybrid wind/solar system is a 48 VDC system. I use the Morningstar 4 Channel Relay Driver. Channel 1 is programmed to energize a standard 48 VDC relay at a DC voltage set point. As an additional backup, I also use a dry contact on the Davis Vantage Pro2 Weather Instrument. I have the Davis Instrument programmed to also apply dynamic braking at a 35 mph or greater wind, to me it's just not worth all the extra wear & tear on the blades and furling system to allow it to continue running. Blades will start back up automatically soon as the wind speed drops a little. Both are wired in series to drop out a 24 VAC standard relay using the normally closed contacts rated at 40 amps to short out the alternator's three phases. In this way if I lost main system power or blew a fuse for some other (unknown) reason, the 24 VAC relay will still drop out and the normally closed contacts will still apply dynamic braking. Spending a little extra time on your emergency shutdown circuits...is well worth it. I've had my share of learning experiences over the years...

Roger Beale's picture

Hi everyone,

Over the past several weeks I’ve been busy upgrading our solar from PWM to MPPT. I installed a Outback Charge Controller, and a additional 2 KW in solar modules.

I also upgraded our 3 KW wind energy system to MPPT (maximum power point tracking). I’ve installed and now experimenting with the Midnite Classic 150 Charge Controller and it's programmable power curves. My blades are no longer locked-in at the 48 volt battery terminal voltage, but can be programmed to now run at a higher rpm speed/voltage than the batteries. It's going to be interesting to see what blade speed (or power curve) will perform best for my blades & TSR at a wind speed of around 12 mph. I'm not really concerned to much about the output at 20 plus mph. Most of our wind is between 10 & 15 mph, I can always heat more water or steal more of the wife's frying pans and toasters for additional diversion dump loads.

I’ve talked to Hugh Piggott and Ian Woofenden about the upgrade, and they provided me some good ideas on how best to test performance.

You can also follow my videos on youtube by doing a search on my name.
http://www.youtube.com/channel/UCx9...

I’ll let you know how the performance test results turn out…
So far...running the Midnite Classic input (blades) at about 10-15 volts higher than Battery looks good...

Roger

Bob Grisdale's picture

I would like to know more about the design, especially the lattice tower. I am retireing and would like to build a similar system.

Roger Beale's picture

Hi Bob,

Sorry I didn't get back to you sooner... I haven't been on-line in a while.

I constructed the Lattice tower from thin-wall steel tubing (Lowes chain link top rails) and electrical EMT tubing. I like using the torch and brass rods better on thin wall metal, a less chance of burning a hole in it...and just as strong (looks good also). I used an old picnic table (good flat surface) and a saw horse to support the lattice sections while constructing.

I used different sizes starting at about 2-1/2" at the base, I brazed welded the 10 foot sections together and also the cross braces. The tips of each brace were placed in a vice and mashed a little to make a better fit before brazing. I would cut enough braces at the same time to construct a complete 10 foot section. I gradually reduced the size of the tubing; the next smaller size will slide very nicely into the larger size. I attached the sections together by inserting about 3 inches for strength and then braze welded all around. When extending the same diameter sizes, I would slide a short 6 inch piece half way into the sections before welding. I use a simple string/center line down the center to keep everything straight before welding. I would taper the last few 10 foot sections by reducing the length (about 2 inches) of the four cross braces. I would always weld the end braces first and work toward the middle of each section. I also welded in some addition crossed flat metal on all four sides for additional strength. I Mig Welded a 3 foot square hinged base using ¼ inch angle iron and concrete footings… 4 foot deep. I use three sets of 1/4 inch steel cable for guy wires, spaced about 30 feet apart.

I started out at about 40 feet and gradually increased the height to 100 feet over a period of about two years. It’s surprisingly strong and has held up very well, also survived the 90 mph derecho back on June 29 that hit Virginia.

You can also follow my videos on youtube by doing a search on my name.

http://www.youtube.com/channel/UCx9...

Hope this helps..and good luck.
Roger

Michael Welch's picture

Hi Bob. I have sent a note to the author and invited him to participate in this conversation. Best of luck with your project.

Roger Beale's picture

Hi Michael,
Sorry I didn't get back sooner... I haven't been on-line in a while.
Very nice job on the page...thanks
Roger

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