wind gen

https://www.aliexpress.com/item/33007260271.html

When there is no sun we have wind.
Would this be a nice addition?
It's rated at wind speeds from 4.5 km an hour if I did the calculation right.


Have a nice sunny and relaxed day to charge your self up.

I've read several times that wind power - especially in a low-wind-area like mine - is not that great and/or you need to push the generator very high in the air. However, I must admit that 1/2 of all this for me is for the fun/learning! I hope you'll share your experiences if you go forward.. e.g. how high in air? neighbors complain? what controller? etc.

100kwh-hunter said:

Its rated at wind speeds from 4.5 km an hour, if i did the calculation right.

Click to expand...

What are you expecting to see out of one at 4.5km/h ?

The problem with toys like that is, to get anywhere near their rated outputs it'll need to be blowing a gale, and, if you run a toy like that in a gale it'll self destruct within a few hours.

But if you can get it up in clear air, so at least 6 meters, and have a moderate breeze you'll possibly see a few kWh/d from it, for a little while - they are good learning toys (disposable)

To get the full power from it, you'd need 1300cm/s wind, or 30mph wind. And this is sustained wind.

Vertical turbines (VAWT) suffer from turbulent winds, and they need to be high to help smooth the wind, and get enough of it to keep turning steadily.
Horizontal turbines (HAWT) don't suffer from the turbulent winds (in fact it works better) and they don't need to be as high. However, they do produce a little less power and are a bit more complicated to install.

With that said, if you live in an area that has very little trees for many acres, and/or can install the turbine up on a hill, then the VAWT should be fine. But don't expect 2000W all day long from it. The generation will go up and down quite a bit like a roller coaster, and just as quickly.

With any turbine, there is also the overspeed issue. If the blades spin fast enough, it'll shred itself to pieces. Do a search for "wind turbine explodes" and you'll see what I mean. You will need a dump load on the turbine to take in any power that doesn't get used, especially if the unit isn't hooked up to any charging devices. And, for stormy weather, you'll want a unit that can have brakes enabled to lock the blades from turning at all.

That WT will never produce 2000 watts.

Essay mk1:

For a wind turbine, if it has more than 3 blades stay away from them unless you intend to use them at low speed (rpm) and in low wind areas (no storms at all). i.e old wild west water pumping.

Agree with Sean, never get to 2000W, very basic to start with, 2000W at 12V would be nearly 170A, aint going to happen, at least not at 12V.... or even 24V..... or even 48V..... maybe around 200V terminal voltage and full carbon fibre blades not the glass fibre ones.

The turbine shown, with 1.3m diameter, 15m/sec nominal maximum (constant) and a cp (blade efficiency coefficient) of 0.2 (generous) would give 571W if your lucky. 2kW, hahahha, Chinese special rating. The problem with 15m/s average wind speed is the gusts may be 25m/s depending on the terrain shape within a mile (see issues later).

Above 15m/sec the risks are with a combination of blade speed and twist (turbine moving out of the wind) pressure, which snaps the blades off if the rotor does not overheat, melt the windings or splig ring bushes. If the slip ring bushes burn out the turbine ends up free running and just disintigrates.

Smaller turbines are typically provided with a (cheap) fixed voltage PWM style controller, which will burn the windings out at higher wattages. A decent controller (or a specific manual switching method) will raise the voltage with output, which then keeps the maximum current limited to what the windings and brushes can handle (brushes in spliring connecting the turbine to cable in/on the pole, not the actual generator). Burning out the splipring bushes or windings is the most common mode of failure for these units, you can't just let them run in a storm or just wave good bye to them.

I have an IstaBreeze 700W unit (24V) and have had over 1.2kW (at 54V) out of it and this was about 8ft off the ground (hub), but you have to hold the turbine direction so this then stops it trying to turn out of the wind and break the blades at high speed. The blades were at the limit around 1.2kW as they were flexing with excess vortex at the tips (significant increase in noise).

The turbine direction was held by couple of thin ropes in my instance so as to keep the unit from moving around and is not a good long term option, but ok for storms and where the wind direction is slow changing when above the free moving level (hours).

This is not an ideal option and was a solution for me for a month, while living at a remote site and not good if you don't read the forecast (due to no mobile reception or the forecast changes) and have to start messing around at 3am in the rain with 40mph winds. After the first instance, it was just roped in direction every 6 hours of a storm or just pulled out of the wind and stopped completely well ahead of an issue storm.

Turbulance is a separate issue and you need to get very high to avoid the damaging gusts that occur like freak waves in the ocean. It is a combination of speed and direction changes that are separate issues to deal with in relation to turbulance. Over power and turning out of the wind stresses, both are separate issues to deal with.

---

Forgot to add, this was a site, where on 2 consecutive days 1kW of solar panels produced around 100Wh of energy due to fog (or rather being in the cloud base)....

---

This is the unit on a brief test in the garden attached to the crane with an extra section of steel.... yup, not a typical wind turbine tower.




The supposed MPPT controller (not PWM as it actually had a step-up stage for low winds), was pretty much useless at higher wattages, ok for light winds, useless above 10m/sec and had a service life of around 40 hours as I had other things to do before swapping it out...

The 1000W grid tie unit I have is also no good for storms becasue it cuts out at 1000W and effectively goes open circuit briefly for a few seconds the unit is also free running.... (amazed the turbine did not self destruct when it happened) so, ended up with the grid tie and a direct battery tap (direct 3-phase bridge rectifier). Below battery voltage the power all goes through the grid tie (with power curve) and then when the rectified peaks of the waveform are higher than the battery voltage these are clipped/shared off to the battery pack. This is not ideal becasue it places an upper cap on the turbine voltage, which then has an impact on the rpm for the wind speed increasing blade stress.

Essay over.

So basically: just in real life it is not really something, just a other toy.
If it must have one gale (wind force 10), to do its job....nah thanks, i thought 0.5 gale (wind force 5) was enough.
If there self life is shorter than a working week....nah.

Thats also why i see them and after a storm(wind force 8 and up) not so much anymore.

Aldo i have the perfect site for a wind generator, acres with no trees, no buildings and i can put it on the roof easy(6 or 9 meters up).
The closest neighbor is 500 meters away.

NAH...
Thanks for the warnings, i will invest 200E more in storage, that is a bigger winner i think

Or water generator, to reclaim something back? the pumps in the pond must work, no matter what.
But it will give a lot of noise, if free falling, and you can not put the generator into the pipe, that will restrain the water flow to much.
Any idea's to play with?

Describe more about the water idea. Heights, size of water path, how far from source to drain.

A properly installed hydro-generator shouldn't cause too much turbulence or slow down in a stream. It will slow the water down a little, as that kinetic energy is transferred to electrical energy. But it won't block the stream, unless it's installed incorrectly.

I have 4 pumps running:each 10.000-12000 liters(2600-3100 gallons) an hour.
Two pumps are the wholeyear running.

The outletabove water level is approximately 10 cm/4 inch.
That could be adjusted from 10cm/4inch to 20cm/8 inch, any higher would probably mean 1000 liters/ 260 gallon loss per 10cm/4 inch higher.

The pipes are 5 cm/2 inch id.
The pumps are in the filter system,so what they pump out of the filter, itflows back in the filter from the pond(law of communicating vessels).
Those pipes are 4 x 12,5 cm/5 inch id.

---

---

The second picture is without the lower pipe, you can imagine that is making some noise.

Thanks.

Hrmmm, only a rise of 4" isn't much head pressure. You'd need closer to a few feet. It could work, but I'd be surprised if you even got 20% recovery.

One of two things are required for hydro-generator.
* High head to create high pressure
* High flow rate to create high pressure

High head can be done in an either/or situation: very wide mouth flowing lots of water, very high altitude difference creating high flow rate. That's why a lot of hydro's use rivers/streams that are 50ft or higher up from where the generator is. There's a few that have tapped a river and diverted the flow through pipes (6" or 8" or larger) on a more direct path to the hydro power shed so there's low loss of flow.

Not saying you shouldn't, or you can't use your setup. But that it'll be difficult to get anything worth in return.

One thing I thought of doing was putting several IBC totes at least 20Ft up and use a windpowered (not wind-electric) to pump water up to the totes, then use that to power a generator. This wouldn't be continuous power, obviously, but it could help power lights at nights, short bursts of power generation if our main power is knocked out, etc, etc.