Just thought I would post this in the thought it may help someone spec their power needs as I always have 100% charge before dark without turning vehicle on ..
I worked on the fact during the day (Summer) the Fridge is using around 2amp per hour, solar panel provides about 4-5 amp (depending on the day). When overcast or cooler, the fridge doesn't draw as much so it balances well with the solar.
My Setup:1 x Blue Top Optima AGM - 55 AH - Under Bonnet.
1 Redarc 1225D (With Solar Input)
1 x Engel 40 Litre. Draw is up to 2.5amps per AH (In Canopy)
1 x 110 w fixed Unregulated Solar Panel using Redarc Solar Input. Max AMP output 5 amp @ 21 Volt. I average about 5 amp in.
Fridge set at 2c with Beers, water and some food.
Average temp - 30-35C during day, 25-30c at night.
With fridge running overnight @2c, battery dropped to 80% (12.5V), Sun hit solar panel at 7am, took 3 hours to fully charge with fridge running (7am to 10am) and sat on 100% all day.
Charging via Solar Vehicle not started for 48 hours - Click image to see full graph:
Charge during day:
Work out your device amp usage and then try double that with solar input if possible.
I was thinking to go to a 200W or even a 160W panel, but, I don't at this stage I don’t need to. Before dark I always have 100% charge @13.2V.
If i increase the solar it appears Ill just get a quicker charge when the sun comes up. 1-2 hours @10amp input. Handy on days when sun is out only a few hours.
We also have a 70 litre Xero Companion Fridge which is around 5 amp per hour draw on hot day and still have 100% charge at dark.
My lighting doesnt really make any difference at all as they draw so little. I usually charge phones/Ipads/Speakers etc during Day.
Hope it helps someone.