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.
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?
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.
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.
I'm also not really sure why one would pick 24V for most applications. 12V makes sense for RVs, boats, etc. because a lot of devices are designed to operate directly off 12V. 48V makes sense for houses and solar installations, if for no other reason than smaller-gauge wires (and is a big reason I'm considering it; 00 gauge wires are enormous and unwieldy). But 24V? You're likely not running much natively off 24V, so you're already going to be doing DC-DC conversion down to 12V. And there's not much cost difference between 24V and 48V inverter systems (and in fact many of them can already handle both voltages).
My first phase DC system, currently in my RV, is a single 12V lead-acid battery, single 100W solar panel, 12VDC->120VAC inverter, a few buck converters for 5V electronics and USB ports, and a bunch of stuff running off 12V (my cell modem/router and my Beelink mini-PC are 12V direct). 12V adapter for Starlink PoE. I'm waffling on getting one or two 280Ah 12V batteries to wire in parallel, or just sticking with my crappy 12V lead-acid battery for the rest of this year and getting multiple 48V LiFePO4 when I do the full solar build-out next year.
You're not supposed to mix-and-match battery brands, manufacturing dates, time in use, etc. because if there's too much of a mismatch, they'll all degrade faster (so I've read). This is what's preventing me from incrementally building up a 12V battery bank by adding another 280Ah every few months. Instead I'm planning to milk what I have as long as possible, pick a voltage, and buy a whole bank of batteries and solar panels all at once.
Yeah, even with 48V, we're still rocking parallel 4/0 copper, it's still a lot of amperage to try to supply 15 kw at 48V. They are heavy. The ones we got from WindyNation were surprisingly flexible, though, which has made them a lot easier to work with.
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.
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
> 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.
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.
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
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
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.