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I do well in my tiny (20') RV for four months a year. It was a little cramped when I had a girlfriend with me, but still cozy. This is my third summer doing thi

I do well in my tiny (20') RV for four months a year. It was a little cramped when I had a girlfriend with me, but still cozy. This is my third summer doing this. The first two summers, I wasn't working. This summer I'm working full-time remote (dev). It has its challenges. I plan to upgrade to a much larger 5th wheel trailer, likely in two years, with all the creature comforts you mention. Part of the reason solar is still a fringe thing for RVs is due to the costs up till now. Another big reason has been solar panel energy density; there simply wasn't enough room on the roof for the thousands of watts you need to generate for true full-time off-grid living with all the creature comforts (most notably air conditioning). Affordable, compact DC-powered refrigerators are still new (but are becoming standard items). Battery cost used to be prohibitive, and battery weight is still a problem. The 1200Ah I'm targeting (at minimum) is going to weigh a few hundred pounds. If you want a residential-sized fridge, washer/dryer, and air conditioning that you can use 24/7, you need more like 3200W of solar and 2400Ah of battery. The larger the RV, the more expensive it is to cool. RVs have crap insulation, and most RVs are used in hotter southern areas. True self-sufficient electric and solar with no behavioral/comfort sacrifice still requires a lot of space and costs a lot. The market is headed toward more solar, but the kind of setup you're talking about (and that I'm building for myself) is still quite expensive. And it's a huge cost for people that don't typically need it; the vast majority of people full-timing in RVs are content to do so at a sardine-packed RV park with full hookups. The market isn't going to bear the cost of massive solar installations as standard equipment.

m463 2y ago
> you need more like 3200W > The market isn't going to bear the cost of massive solar installations as standard equipment. so doing some math... Larger class A RVs seem to cost $300k and up, and retirees seem to happily pay for all conveniences. For "normal" people, who haven't cashed in their retirement, the good thing is that they depreciate like a car instead of appreciating like a house. if you used all of a 40ft RV roof (40'x8') you could get ~ 5000 watts If you had fold-out solar awnings, I don't know what you could get... 10k? 15k? With a large tesla battery pack, you could get 100kwh of batteries. I remember when tesla first came out with their cars. The batteries seemed unnecessarily large and expensive compared to 24 kwh batteries in other cars. But they survived the test of time/longevity being both practical and not charged and discharged 100% every day. I think it will happen, I just wonder when.
- caymanjim 2y ago
  Alas, houses appreciate, cars depreciate, and RVs are just worthless. I exaggerate, but RV depreciation is absolutely nothing like auto depreciation. They lose 25% driving off the lot and another 25% per year (numbers out my ass, but correct order of magnitude). The cost certainly would the most make sense on gigantic $300k class As, which also conveniently have space for lots of panels and lots of batteries. And indeed you see the most elaborate factory-installed solar setups on those beasts. That's a tiny market, though. I think you're right about the future. It won't be long before thousands of watts of solar come standard on most RVs. In fact I don't think it will be all that long (decade or two maybe?) before the RV is clad in some kind of solar material. Like every square inch of the surface is generating solar.
  - nothercastle 2y ago
    They are built so terribly most are worthless after 20 years and start to have major issues at 10. Also add that the first 2 years they are constantly in the shop for repairs while the warranty is still available
    - foobarian 2y ago
      I know some people that like to buy used trailers and then spend tons of their time fixing and complaining about leaks, rotted vinyl, etc.
      - nothercastle 2y ago
        Yeah I don’t get it you can’t build quality into a shitty design. Only trailers worth repairing are airstreams and fiberglass ones, and even then the time to value proposition is dubious
ericd 2y ago
I'm curious, why do people use Ah for batteries, given that there's 3 different common server rack battery voltages (12, 24, 48)? Is 12 just assumed for RVing?
- stephen_g 2y ago
  Amp hours are what the batteries are specified in, right down to cells that are 1.5V, 2V, 3.9V etc.. Yes, once they're in system you want to know kWh capacity of the system as a whole, but it makes sense that people think of what's written on the batteries first.
  - kragen 2y ago
    caymanjim knows his units, but the general public is so ignorant that it's common to hear people confusing a 1200-amp-hour battery with a 1200-(cold-cranking-)amp battery. even people who built a multi-voltage electrical system for their rv. the struggle is real
- caymanjim 2y ago
  You make a good point. They really ought to be sold with Wh prominently displayed. I'm talking about 1200Ah@12V, although in reality there's a good chance that I'll do 600Ah@24V or 300Ah@48V. It's all the same 14.4kWh and will provide the exact same amount of usable power (ignoring some conversion efficiencies). I'm using Ah because I'm used to talking to people about 12V battery systems, and Ah is the most prominent number when talking about battery capacity (when the voltage is already implied or agreed upon). You're absolutely right though, and I should have been more clear about it.
  - ericd 2y ago
    Ah makes sense (that 12V is just implied for RVs). I'm used to dealing with 48V, since I'm doing this for a house, and it seems like they specify batteries both ways in that world. I wonder who uses 24V. Anyway, thanks for explaining it.
    - 2y ago
kragen 2y ago
i very much appreciate you sharing your knowledge!

m463 2y ago

> you need more like 3200W > The market isn't going to bear the cost of massive solar installations as standard equipment. so doing some math... Larger class A RVs seem to cost $300k and up, and retirees seem to happily pay for all conveniences. For "normal" people, who haven't cashed in their retirement, the good thing is that they depreciate like a car instead of appreciating like a house. if you used all of a 40ft RV roof (40'x8') you could get ~ 5000 watts If you had fold-out solar awnings, I don't know what you could get... 10k? 15k? With a large tesla battery pack, you could get 100kwh of batteries. I remember when tesla first came out with their cars. The batteries seemed unnecessarily large and expensive compared to 24 kwh batteries in other cars. But they survived the test of time/longevity being both practical and not charged and discharged 100% every day. I think it will happen, I just wonder when.

caymanjim 2y ago
Alas, houses appreciate, cars depreciate, and RVs are just worthless. I exaggerate, but RV depreciation is absolutely nothing like auto depreciation. They lose 25% driving off the lot and another 25% per year (numbers out my ass, but correct order of magnitude). The cost certainly would the most make sense on gigantic $300k class As, which also conveniently have space for lots of panels and lots of batteries. And indeed you see the most elaborate factory-installed solar setups on those beasts. That's a tiny market, though. I think you're right about the future. It won't be long before thousands of watts of solar come standard on most RVs. In fact I don't think it will be all that long (decade or two maybe?) before the RV is clad in some kind of solar material. Like every square inch of the surface is generating solar.
- nothercastle 2y ago
  They are built so terribly most are worthless after 20 years and start to have major issues at 10. Also add that the first 2 years they are constantly in the shop for repairs while the warranty is still available
  - foobarian 2y ago
    I know some people that like to buy used trailers and then spend tons of their time fixing and complaining about leaks, rotted vinyl, etc.
    - nothercastle 2y ago
      Yeah I don’t get it you can’t build quality into a shitty design. Only trailers worth repairing are airstreams and fiberglass ones, and even then the time to value proposition is dubious

ericd 2y ago

I'm curious, why do people use Ah for batteries, given that there's 3 different common server rack battery voltages (12, 24, 48)? Is 12 just assumed for RVing?

stephen_g 2y ago
Amp hours are what the batteries are specified in, right down to cells that are 1.5V, 2V, 3.9V etc.. Yes, once they're in system you want to know kWh capacity of the system as a whole, but it makes sense that people think of what's written on the batteries first.
- kragen 2y ago
  caymanjim knows his units, but the general public is so ignorant that it's common to hear people confusing a 1200-amp-hour battery with a 1200-(cold-cranking-)amp battery. even people who built a multi-voltage electrical system for their rv. the struggle is real
caymanjim 2y ago
You make a good point. They really ought to be sold with Wh prominently displayed. I'm talking about 1200Ah@12V, although in reality there's a good chance that I'll do 600Ah@24V or 300Ah@48V. It's all the same 14.4kWh and will provide the exact same amount of usable power (ignoring some conversion efficiencies). I'm using Ah because I'm used to talking to people about 12V battery systems, and Ah is the most prominent number when talking about battery capacity (when the voltage is already implied or agreed upon). You're absolutely right though, and I should have been more clear about it.
- ericd 2y ago
  Ah makes sense (that 12V is just implied for RVs). I'm used to dealing with 48V, since I'm doing this for a house, and it seems like they specify batteries both ways in that world. I wonder who uses 24V. Anyway, thanks for explaining it.
  - 2y ago

kragen 2y ago

i very much appreciate you sharing your knowledge!