RV Solar Series: Limit of the design. Everything has limits. The limits I have are daily sunshine is required and battery size and type.
Even though I met all the design goals, I need to have the sunshine every day. In the summertime, I will have much longer daylight periods to charge the battery. The efficiency of the panels will drop because of the warmer temperature, but the effectiveness will increase due to the higher sun angles and longer exposure. My setup should be able to crank out 150+ amps even on the shortest winter day assuming a clear sky. In the summer, assuming sunshine, I should be at 100% well before noon.
The design has met the goal. The shortfall of my system is one obvious item. What if the sun doesn’t shine?
One possible answer on cloudy days is to quit using so much electricity. My heater (4 amps), inverter (4 to 10 amps) and refrigerator (3 amps) are obvious targets for conservation.
Other than conservation, my backup plan is to run the generator.
So this begs the question of how to maximize the system as it currently stands and the answer is very easy. I need more storage. If I had three hundred amps of useable storage I could then go an additional day without sunshine before I had to recharge.
Now here is the problem with 300 amps usable (600 amps lead-acid) storage. Each box included in my battery weighs more than 90 lbs (180 lbs total) and now I need, not two boxes but rather, four boxes, each weighing 90 lbs (360 lbs total), and I need room for four big boxes. It doesn’t take much to figure out that I don’t have room for bigger boxes, nor do I have room in my weight carrying capacity for an additional 180 lbs of lead.
Doubling my storage will only allow me to bridge one day of clouds. What I need is a higher capacity, lower weight, and smaller storage.
RV Solar Series: The limit of the design is essentially my battery.
Update February 20, 2020, our battery won’t be the limit of our design for very long. We have sold our 2013 RV and purchased an older nicer, more power-hungry RV. Make sure to check for updates on how we are going to raise the bar both on battery and on our solar install.