I picked up a “600W” Wind Turbine back in 2016.
After opening the box and beginning assembly, I noticed that the shaft of the wind turbine did not rotate – it would move slightly either direction and then I’d hear a light *crunch*.
Normally I’d return/exchange but since I’d got the “last one” from this Amazon seller at a really good price (and it did appear to be new), I decided to try and find/fix the problem.
I unscrewed and removed the front cover and found the issue – one of the magnets was broken and the chunk of magnet that had broken off was jammed. It took some careful disassembly (the magnets are strong enough that the rotor can abruptly sheer off a finger), but I got it fixed.
With that fixed, I didn’t have any other initial issues. All seemed well.
I’ll skip installation except to mention it’s really heavy so if you’re roof-mounting it, consider leaving the hub/blades off until you’ve got it on the roof. You’ll want a 2nd person handy.
(is it blurry because of the camera, because it’s spinning, or because I’m bad at taking pictures? trick question! it’s all 3!)
Technical Bits and Quality Issues
This is the 12V version of the WG700. 3-phase wiring.
I have it hooked up to a custom controller, and the realistic voltage range for this unit that I’ve seen is from 0-30 volts, with 30 volts being across a 1 ohm load at really high wind.
In tests with a 12V inverter, the realistic voltage range was 11-16 volts, though it did hit 24 volts with really high winds at which point a dump load kicked in.
Note that the MPPT inverter I tried did a fairly terrible job and I’d strongly recommend against using any of these solar-intended MPPT inverters.
The blades are listed as FRN – I did some digging and my best guess is this means “Fibreglass Reinforced Nylon”. They’re painted white (some was chipped), and while I repainted with some good oil based rust paint, I have no idea what the longevity will be with UV exposure.
The blades were NOT balanced and would cause vibration at certain speeds (typically correlated with around 16 volts unloaded). The blades appear to be created from larger blades that have the ends sawed off.
The manual mentioned an electromagnetic brake. It doesn’t have one. I think they mean you have to brake it manually (shorting the leads).
The unit itself is painted white. No drainage I could see, so when I had the front cover off I drilled a small weep hole in the bottom so that any moisture that gets in can escape.
The blade end is heavier than the tail end – strong winds can cause the unit to “rock” back and forth on the vertical shaft bearings, causing vibration. I experimented with a heavier tail at one point which solved this (by keeping the unit always pivoted to the rear). Ideally the unit would have come with 2 vertical bearings that had no play, but it either only has 1 or has 2 that aren’t very tight.
Wind Speeds and Performance
We have the turbine mounted at somewhere between 25-40 feet in the air. Note that higher is obviously better.
I also made a custom controller so that I can extract power at both low and high voltages while varying the load placed on the turbine. I may do a write-up on that later.
Either way, keep in mind that between different mounting, different heights, different landscape, and different controllers… your results probably won’t jive with mine.
- 11km/h or 7mph (3m/s) – The wind turbine will turn when unloaded (freewheeling). When a load is applied, we get 1 watt or less. Voltage won’t exceed 10 volts even when unloaded. Yes, it turns but it’s useless at this speed.
- 22km/h or 12mph (6m/s) – Around 5 watts is the most that can be pulled from the wind turbine.
- 30km/h or 19mph – At around this point we’ll start seeing some real (slightly useful) power. We’re talking the 20-50 watt range.
- …from there it actually starts moving up rather exponentially.
HOWEVER, the 600W rating we only see on days where the wind is something in the neighbourhood of “winds of 50km/h gusting to 70km/h” (30-44mph)“.
THE MAX I’ve seen it put out over the last year has been just over 1000W. These are the few days of the year where shingles risk being torn off the roof (wind gusts to 80-90km/h).
In short, any power I’ve seen below 30km/h (20mph) has been negligible. It really doesn’t do much until it reaches and passes that point. Once it hits that point, every extra bit of wind increases power noticeably.
3-blade vs 7-blade – experiments
For a period of time, I swapped in a 7-blade assembly with hub from Missouri Wind and Solar. It has slightly less diameter but a lot more blades. This *does* produce more power at the lower wind speeds. Unloaded, it doesn’t start spinning any earlier though.
The big downsides to the 7-blade are as follows:
- It spins slower. Unloaded, the 3-blade will spin up to a pretty high speed at low winds while the 7-blade won’t spin up as fast. So if you need to hit a certain voltage threshold it’ll require a bit more wind to do so.
- Doesn’t handle gusts quite as well. Susceptible to being stalled and thrown out of the wind.
- Gusts from different directions will throw it out of the wind very easily. It can take a while to re-position and spin up again.
- At really high winds it *does* stay lined up, but you can NOT slow down the blades even by dead-shorting it.
- Stalls more easily in general. If you try to pull too much current, the blades will stall and the thing will have a tendency to get thrown out of the wind even more easily.
Positives replacing the 3-blade with the 7-blade:
- I trust the material from the MWS sword-blades to handle the elements quite a bit more – they’re quite durable.
- More power can be pulled at lower speeds because the 7 blades allow for more torque. So while it might take more wind to hit 12 volts, you can actually pull some power out of that 12 volts.
- When the turbine is hooked up directly to a resistive load (heater for example), the 7-blade can actually start turning at a reasonable wind speed, whereas the 3-blade will stay stalled until winds are so high that it’s forced to move.
If you plan to upgrade to a 7-blade assembly and hub, you may want to consider a larger tail or a tail extension to keep it in the wind. I’ve tried a larger tail which helped, but a tail extension would probably work better with the tradeoff being a little harder to custom fabricate.
In short, when it comes to power being pulled, I’m leaning towards the 7 blade being the way to go. Sure, you have to deal with gusts, being thrown out of the wind, stalled due to too much power being pulled, stalled for other reasons, and the inability to slow it down under high winds, but hey…. if you can deal with all of that, more power is more power.
If you’re looking to step into small-scale wind at the home or cottage for something simple (charging a battery bank or heating water while you’re away for instance), these lower cost wind turbines can be worth a look if you’re really just looking to test the waters.
The “600 watt” rating is something you’ll only hit a few days of the year without extremely high mounting and great wind conditions, they won’t let you go off-grid by any means, and the hardware (mounting, controller, dump load, wiring) will probably cost more than the turbine, but it’s a way to dip your toes in the realm of wind energy.
That said, if you’re really hoping to do some real power generation, you may want to go with something quite a bit bigger/better.
As it stands, I’d classify these Aleko/Gudcraft 600-700 watt wind turbines as being in the “hobbyist” or “beginner” realm. Don’t expect to generate tons of power, but expect to learn a lot in the process.