Good info, very useful, thx! So 200Ah and a 55A charger. Interesting. I have a Tune, so very similar to Alu-Cab canopy camper.
I found that most people overestimate the power requirements for induction cooking and massively underestimate the inefficiency of propane – the slightest wind can bring efficiency down way below 1/3 of the efficiency of induction. Even taking the number above regarding a 20lbs bottle having 95 times the energy of a 100Ah 12V battery, following that math means 47 times the capacity I have, at best efficiency for the propane that would result in about 16 times usable power. And that's in the best of circumstances, no wind and a good stove or range – the efficiency number is from the Department of Energy for home use. Which doesn't account for wind driving the flame away from your pot – which can easily take away another 50 to 80% of the produced heat.
Most of my cooking happens at 400 to 600W according to my Kill-A-Watt meter. Initial heat up with 1200 to 1500W, I don't go full high since I don't want to kill my pots and pans, then I can turn it down significantly. We heat water with an electric kettle, it's not as fast as a MSR Windburner, but not much slower either.
I've tracked a few things I regularly cook regarding their power consumption:
Task | Ah needed |
Boiling water for coffee or tea for two people, three to four times a day | 5Ah per two big mugs |
Cooking scrambled eggs, no other incredients, we will do this only sometimes, not every day | 5Ah |
Cooking a one pan dish with chicken, vegetables, rice (pre-cooked rice) | up to 40Ah (but that's an upper limit, did it twice, one was around 30Ah, the other around 37Ah, it depends on the incredients) |
Cooking noodles for two | 15Ah |
Re-heating left overs | 5Ah to 10Ah |
Scrambled eggs with veggies (including mushrooms which take rather long on high(ish) heat to evaparate moisture and cook down a bit) | 20Ah |
So, most of these take a max of 20% of my overall battery capacity. We rarely ever drive less than two hours per day which would re-charge 50% of the total capacity I have which I have so far not ever used in a single day. Plus there is solar. Currently I don't have solar installed, but plan on a 150W CIGS panel at some point. That should extend the time we could stay in a single place to three days depending on weather. We haven't stayed longer than two days in a single place so far.
Oh, and IF we go into a hotel, we can use our gear in the room to cook there ...
UPDATE: corrected my own math, it's 95, not 85 times ...