24V battery bank with solar - pros and cons
Hmmm.... should I go with a 24V Battery bank? I am in the planning phase of a 800 to 1,000 Watt solar system for my 5th wheel. I am thinking maybe a Morningstar TS-MPPT-60 charge controller and 4 ...
Forum Discussion
I have 3x250W panels in series each with 3 bypass diodes and a MPPT 60 controller. The panels do very well in lower light situations and in partial shade. I've posted 3 threads on the effect of partial shade with bypass diodes. Here's one. The graph clearly shows how 1/3 or 2/3 of a series panel can produce power with bypass diodes while a partially shaded parallel panel would produce no power. Plus if one panel is in full shade and the diodes are conducting for example I still get full power from 2 panels. Even if 7 diodes are conducting that still leaves 2/3 of a panel (about 20V) available for charging.
And as you suggested adding a 4th panel would require a series/parallel connection. I'm not sure how partial shade would work on this setup. For example 2 panels in series is 60V which are in parallel with 2 panels with partial shade and one diode is conducting resulting in 50V. Now you have 50V and 60V panels in parallel and perhaps the 2 50V panels don't produce the expected power?
My panels are flat mounted, 4 degree slope and they are mounted 7.5" above the roof on one end. This eliminated all rig related shadows regardless of rig orientation when the sun elevation was more than 10 degrees. And you get very little charging with the sun below 10 degrees anyway.
And as you suggested adding a 4th panel would require a series/parallel connection. I'm not sure how partial shade would work on this setup. For example 2 panels in series is 60V which are in parallel with 2 panels with partial shade and one diode is conducting resulting in 50V. Now you have 50V and 60V panels in parallel and perhaps the 2 50V panels don't produce the expected power?
My panels are flat mounted, 4 degree slope and they are mounted 7.5" above the roof on one end. This eliminated all rig related shadows regardless of rig orientation when the sun elevation was more than 10 degrees. And you get very little charging with the sun below 10 degrees anyway.
