Using two lower-volt wind-gens instead of one higher-volt?

[spinningmagnets]

Jerry posted this in another post. I thought it may have merit and wondered what others here thought (he didn't get an answer as it was OT):

"...I would build 2 matching wind gennies. I would use two 6-volt golf cart batteries. Each gen would charge a 6-volt battery. I'd wire the batteries in series for 12V..."

In a perfect world, when I retire I'll have many acres where I'm allowed to have a 60'-80' tower, and I have fairly strong and steady winds for a large 48V wind-gen.

I'm still learning, but it seems one of the most common complaints is poor low winds where its hard to get cut-in for a 48V wind-gen.

Is there any benefit to having two battery packs, each with two 24V sections. While one  2 X 24V pack is charging (off a 24V wind-gen or solar PV), the other 2 X 24V pack is powering the 48V inverter.

I realize this requires frequent manual switching, but if someone had winds that had difficulty getting much 48V, could I get more Watts for the extra trouble?

[wpowokal]

There is only so much power in the wind at given speeds, now if that is harnessed at 24V or 48V is irrevevent.

Simply build a stator for 48V and avoid all the battery hasels.

allan down under

[Flux]

No advantage at all.

You can get cut in at any voltage and any wind speed that turns the prop by suitable alternator design. What you can't do is get more power than there is in the wind at any given wind speed.

If your windmill will start turning in a 5 mph wind then you can wind the alternator to produce 48v at that speed if you wish. When it starts to charge the battery the current will be limited by the energy in the wind and it may stall at a few milliamps.

A sensible machine is designed to extract power from the lowest USEFUL wind speed.

If you are trying to use some motor or other commercial thing that is not designed to do what you want effectively then it may not reach charging speed in light winds. In this case trying to charge split batteries with two machines would give some useful results when otherwise it would fail but it is not a convenient idea and needs constant monitoring to keep battery charge in step.

I suppose you would have the option of doing a 2:1 voltage change on both machines so that they charged half volts in light winds and were switched to the full battery volts in high winds but this is nothing more than could be done with star/delta and nobody seems to bother with that.

Two machines will obviously be better than one, but two decent ones feeding in parallel are more practical than any half baked series scheme. It may be better use of materials to throw all the magnets into one bigger machine rather than have 2 small ones but that depends on other factors.

Flux

[spinningmagnets]

I've actually wondered this for quite a while. I've just been too embarrassed to ask, and I also thought if I waited long enough, someone else would ask it.

Thanks for the thoughtful response, Flux. I appreciate your help and willingness to share your technical expertise.