Charging hours with higher voltages

JoshK

I see the term "Sun hours" around a lot, but if you have say 13 panels in a series rated at 600v, it would seem to me you would be able to keep the voltage high enough to charge during all hours of the day... with reduced watts of course. Maybe even a moon lit night?? Is this a benefit of a high voltage configuration or not?

Vic

Hi Josh,

PVs are (not perfect) Current Sources. There is very little current, and therefore little power available at times when the sun intensity is low. So, even if an array could produce several hundred volts under low light conditions, there is little current available, and so little power, available for feeding the Grid, and/or little charge current available for a battery.

If one doubled the size of a PV array by doubling the number of PVs in series, and therefore doubling the Vmp and Voc of the array, there would only be double the amount of power available from that array.

Make sense? Vic ... OH, and regarding your SIg line, Solar Hardware, especially PV modules, have gotten MUCH less expensive in the past few years, OR, many of us adopted rural living and Solar systems much too early! VB

JoshK

I'm hoping the monocrystalline panels I chose perform better than poly with marginal light, but maybe not much? I don't know. I got interested in solar lately because I knew the price had come down, but when I priced my dream system it was like $40,000. Ouch. Now i'm just trying to muster a backup system that can run one load on a daily basis, even when the grid is up.