Battteries do not hold charge overnight

dont know enough to help yet.

amp hours on batteries?

run time on pumps? 

170w for each pump or for both?


james
Alt-E staff

well, 170w x 4 hours = 680 watt hours
680 watt hours x 1.10 = 748 watt hours (inverter inefficiency)

production:  260w x 4 sun hours per day = 1040 watt hours /day
1040 watt hours per day x .80 (inefficiency) 832 watt hours per day.

that means that on a good day, your system barely gets the job done.  if your day is less than optimal, your system takes it out on your batteries, which is why the system behaves like it does.

to rectify this either the loads decrease, or the input increases.  adjusting the batteries will give more of a buffer, like a savings account.  but ultimately, spending more energy than you produce will create a shortfall that in your case will cause premature wear and eventual failure of your batteries.

james
Alt-E staff

Allen, you could try using newer, less power drawing pumps and reduce your power demand. You can get common circulators that run at 1/32 HP or around 20-25 Watts at 110 Volts. Though you may have to purchase a small inverter to run off your 24 volt system. This would be almost the same cost as adding more PV.