Posted by DJ on July 21, 2004, 2:05 pm
I'm chasing this down on my own, but wonder if someone else might
have already solved it.
I've got a client who wants to add a photovoltaic array (6x75watt)
and a windmill (H-80) to their system.
The challenge is that the two most suitable locations are about 60
meters away (200 feet ;-). This is further challenged by the fact that
their inverters and battery banks are configured for 12v. Switching
the inverters is not an option, nor is linking them.
Now, the photovoltaics are easy. An MX-60 would allow me to put all
the panels in series or a combination of series/parallel and thereby
run smaller, less expensive wiring to their input, and have the MX-60
output the correct voltage for their 12v bank.
The windmill, though. As it sits now, as a 12V system, I'd need to
run something in the neighborhood of 4/0 by the little "Perez
Calculaton" I have. In Canadian dollars, that's the WRONG side of
1000$ just for wire.
Of course, if I can jump up to even 24 or 48V, then I'm back down in
the realm of "cheap wire", which will make my client happier ;-).
So, any ideas? I've already contacted SouthWest.
Posted by Steve Spence on July 21, 2004, 8:56 pm
You could use an inverter at the wind mill and run 110vac back to the house.
Posted by DJ on July 22, 2004, 1:44 am
Yep, considered that. Then I'd need a transformer to put it back to
12v DC... basically a battery charger at that point, and then that
input into a charge controller, or with a load diversion controller
like a C-60 at the bank. But yep, not a bad idea.
Posted by N. Thornton on July 24, 2004, 11:02 pm
email@example.com (DJ) wrote in message
I'm unsure about that one for 2 reasons:
first the charger will take current only at the V peaks, which means
the invertor will only be able to provide a fraction of its specified
power output to the charger.
second, when the charger is trying to charge with higher current, on
its assumption that the mains is 110v, but the windmill isnt
delivering so much, the invertor would either sag or cut out. If it
just sags teh charger may or may not work ok with that, and respond
correctly. Good chance it wont.
One effective solution might be a switched mode 12v regulator. Theyre
not hard to make with a bit of tronics knowledge. It takes whatever V
the mill offers it, and outputs 12v, or better 14.4v for charging.
Switched mode means it has a transforming effect, so it wont waste the
V difference in heat.
Even solar charge controllers will be used to dealing with more than
the battery bank voltage, so you might possibly be able to find one
that will do it directly. Advantage would be multistage charging plus
ready made. I say that without being too up on the commercial products
ready available. Its really the DIY reg approach that I know is
Or one could make a reg that delivers say 16v and feed that to a ready
made (solar) charge controller.
Posted by Bob S on July 21, 2004, 9:49 pm
I think that the H80 charge controller comes with a hv/lv option. So,
you can run high-voltage (240v ?) wild 3-phase from the windmill, and put the
charge controller near the batteries. The charge controller will
convert it to 12v dc.