Solar question
I am working through the solar deal hopping to have something in place for the spring. Right now I am looking at 200 to 250 watts worth of panels that I can expand in the future. Just so I understa...
Forum Discussion
Hi RLS,
I would not do an MPPT system at 24 volts. Mine is 33 and if I upgrade I'll go to perhaps between 80 and 100 volts.
But, in pure theory, the MPPT (even on 24 volts) ought to be able to outperform as far as equalization goes, in poor solar conditions. (cloud and haze)
However that is NOT a reason to go MPPT. Equalization is, at most, a once every 30 day situation with a properly sized solar farm. The minimum size is 60 amps (or to speak BFL's language, 5 amps) per 100 amp-hours of storage. Meet that need and I don't care if you use an old style "on, off" controller, it will work well.
MPPT is almost always more expensive than PWM for a similar sized system. If the whole system is cheaper, then go for MPPT.
I would not do an MPPT system at 24 volts. Mine is 33 and if I upgrade I'll go to perhaps between 80 and 100 volts.
But, in pure theory, the MPPT (even on 24 volts) ought to be able to outperform as far as equalization goes, in poor solar conditions. (cloud and haze)
However that is NOT a reason to go MPPT. Equalization is, at most, a once every 30 day situation with a properly sized solar farm. The minimum size is 60 amps (or to speak BFL's language, 5 amps) per 100 amp-hours of storage. Meet that need and I don't care if you use an old style "on, off" controller, it will work well.
MPPT is almost always more expensive than PWM for a similar sized system. If the whole system is cheaper, then go for MPPT.
RLS7201 wrote:
Mr. pianotuna, I have a question for you and BFL13.
Lets set up 2 systems.
1: 500 watts of 12 volt solar w/PWM and 4 6volt GC batteries, configured at 12 volts.
2: 500 watts of 24 volt solar w/MPPT and 4 6volt GC batteries configured at 12 volts.
Question, will either system stand a better chance of equalizing than the other (15.5 volts) on a slightly over cast day?
Thanks
Richard
