Alright-Solar powered Rubicon year 3 is in the bag. Here is a report and some actual data!
I started the Rubicon trail last Sunday and set up that afternoon at Buck Island for a 4 day stay. 160 watt solar panel deployed on the roof, facing south, elevated to 14 degrees to optimize power harvest. Also supplemented with a 100 watt panel on a separate charge controller) to face the morning sun and gather the first rays of the day. It turns out this 100 watt panel wasn't needed at all, but more on that later.
I was running 2 refrigerators, one of them an Engel 45 from 2003, and the other a much older Sawafuji-Norcold unit I got off of Craigs list. Sawafuji is the original manufacturer of Engel, ARB etc. They still make the Engels in Thailand, though mine is a Japanese one I believe from the mid 1980s.
The real news this year was the new Victron BlueSolar MPPT controller. In camp the first day,
@TrickyT and myself took a hint from
@george_tlc and ran the fridge power through the output terminals of the charge controller, because it would then log power consumption and we could easily measure basically all of the consumed power for our stay. The data is provided below. You can see my power consumption peaked on day 2, running 2 fridges at about 37 amp-hours (Wh reported below and more accurate). That's less than I had planned for, and a real testament to the power frugal nature of these fridges. Also interesting that the two fridges averaged about the same power consumption total, even though the older one draws 4.7 amps running and the newer one draws 2.7 amps running. (that's based on past year"s average power use by the Engel alone)
You can see based on the numbers, the power use was variable, but close to the same, and the panel could more than keep up with use. Even with 2 fridges the batteries would hit absorb stage by mid morning and then just float the rest of the day, ramping up panel power when a fridge came on.
The low voltage number reported is mis-leading. The resting voltage of the battery first thing in the morning with both fridges off was typically 12.3-12.4 volts. When they both started, it would momentarily drag the voltage down and the controller would log that as the "low" voltage of the day.
We used my 100 watt portable panel to supplement
@TrickyT 's 60 watt panel, because the 60 watt had a bit of a tougher time fully charging his battery. My conclusion from that, is that 60 watts is almost enough for a typical camping load, but really a 100 watt panel should be considered the minimum for this type of use.
One other thing-Renogy sells this as a 100 watt folding panel, and
@e9999 was concerned the company was not telling the truth about the output. Since my Victron app could also see
@TrickyT 's controller, I saw 101 watts several times, so I think the panel is a legit 100 watt panel in real world conditions.
Conclusion: total success all around, the Victron MPPT with the bluetooth control is excellent and fun to use. There is some question about the consumption logging accuracy but I'll let
@george_tlc comment on that, but I believe up to a 7% error was quoted.
My data from 2017 Rubithon: