These are very reasonable questions that I learned about the hard way camping in the desert two years ago. I do not recommend boondocking in central Wyoming in August.
First, because when you live in an aluminum box with 1″ thick R7 walls you need more air conditioning in summer than that much solar can provide. It doesn’t help that RV air conditioners are designed to be small and light and cheap (most people only use them a handful of days a year), so they’re much less efficient than home air conditioners, even window units. I have 2x 15k BTU/hr AC units, and can only run one at a time on my inverter (they use 1400-1800W each). On very hot days (>90-95F) I need both at least some of the time.
Second, because the conversion efficiency of silicon PV falls at high temperatures, so hot and sunny summer days are actually not my days of peak production.
Third, my batteries and inverter are unfortunately but unavoidably placed in a closed compartment with limited airflow covered in black painted aluminum. And consumer grade inverters are not great, there’s something like 15-20% loss (heat generation). That means on hot days it’s sometimes challenging to keep these from overheating, and running the generator to give the inverter a break while the batteries recharge can be helpful.
Fourth, in addition to low solar production in winter, electricity consumption in an RV is higher than you might expect in cold weather. The propane furnace draws electric power for the fan. Since the plumbing is exposed to air, you need electric tank and line heaters for the fresh water tank, waste water tanks, and water lines to avoid freezing. I also use electric tank warmers for my propane tanks, since when the weather drops below freezing a partially-empty 20 lb tank can’t supply the steady 30k BTU/hr the furnace needs (it normally relies on ambient heat to boil off liquid propane, and at low T in a small tank that doesn’t happen fast enough, which can cut supply and even freeze the regulator). On a cold winter day, I’m probably drawing an average of 300-600 watts just to keep the plumbing and furnace working well. Granted, not many people winter in an RV in Massachusetts, I’m an unusual case. I wouldn’t have this problem in most of the Southwest or Florida where other RVers go.
These are very reasonable questions that I learned about the hard way camping in the desert two years ago. I do not recommend boondocking in central Wyoming in August.
First, because when you live in an aluminum box with 1″ thick R7 walls you need more air conditioning in summer than that much solar can provide. It doesn’t help that RV air conditioners are designed to be small and light and cheap (most people only use them a handful of days a year), so they’re much less efficient than home air conditioners, even window units. I have 2x 15k BTU/hr AC units, and can only run one at a time on my inverter (they use 1400-1800W each). On very hot days (>90-95F) I need both at least some of the time.
Second, because the conversion efficiency of silicon PV falls at high temperatures, so hot and sunny summer days are actually not my days of peak production.
Third, my batteries and inverter are unfortunately but unavoidably placed in a closed compartment with limited airflow covered in black painted aluminum. And consumer grade inverters are not great, there’s something like 15-20% loss (heat generation). That means on hot days it’s sometimes challenging to keep these from overheating, and running the generator to give the inverter a break while the batteries recharge can be helpful.
Fourth, in addition to low solar production in winter, electricity consumption in an RV is higher than you might expect in cold weather. The propane furnace draws electric power for the fan. Since the plumbing is exposed to air, you need electric tank and line heaters for the fresh water tank, waste water tanks, and water lines to avoid freezing. I also use electric tank warmers for my propane tanks, since when the weather drops below freezing a partially-empty 20 lb tank can’t supply the steady 30k BTU/hr the furnace needs (it normally relies on ambient heat to boil off liquid propane, and at low T in a small tank that doesn’t happen fast enough, which can cut supply and even freeze the regulator). On a cold winter day, I’m probably drawing an average of 300-600 watts just to keep the plumbing and furnace working well. Granted, not many people winter in an RV in Massachusetts, I’m an unusual case. I wouldn’t have this problem in most of the Southwest or Florida where other RVers go.
(I really like how gears-y your comment is, many thanks and strong-upvoted.)