Thanks!
That's a great question. One that I'll leave to people that enjoy math.
"Not long" is the straight answer - so yes it's more of a shore power thing.
If anyone cares to do the math:
On low, it uses 650 watts
I have 2 Interstate Group 31 RV batteries (Costco)
Currently the solar panel isn't hooked up.
Using a 2000 watt inverter
I ran the AC and the fridge yesterday as a test for several hours. Direct sun on a black trailer made for a 90+ degree starting temp. Didn't take more than 2-3 minutes to cool it down. Figure 80 square feet with 8000 btus - even with no insulation on the roof and definite air leakage it's well oversized. Assuming I'm camping without shore power, I'll likely stick to a fan - or run it shortly at the beginning of the evening and hope to seal in the cold air.
Currently only have a single 100W solar panel, I'm interested in figuring out how much much time that will buy me - and if it makes sense to grab another panel or two. I'm fairly certain I could fit 4 panels on there if need be.
Really hoping to be able to run a full weekend with the fridge on and intermittent AC. Mounted the hot water heater last night - gonna run the faucet plumbing tonight after I bleed the brakes on the 60. Hoping that's the last remaining issue (for now) on the 60 and I can take it this week.
Otherwise it's yet another trip in the 40 with no heat/AC and a 60mph comfortable top speed with the trailer.