I realize the community forums aren't very active and a several Rialta folks are moving on to other living arrangements, but surely someone will find this helpful. On the topic of summer heat, I realize I could’ve relocated to another climate, but I love the community in Austin and decided to put my time, money, and energy into improving my living space over relocation costs plus building a new community elsewhere. Big ups out to Dave R. for proving the possibilities of solar-powered air-conditioning, out to J. Donna for all the enthusiasm, help, friendship, free tow, and new tires, and of course out to Tynan for sharing all kinds of fantastic hacks and leading us to RV life. Tynan, I don’t know where I’d be without a marine fridge, great find!
Yes, the new array reliably runs both runs the 5kbtu air conditioner and charges my batteries simultaneously from 10AM-5PM. I only having 4 golf cart batteries, so I usually shut off the A.C. after 5pm because my panels are permanently mounted flat (not tiltable towards a sunset) and I simply don't have the battery capacity to run it at night. Yamaha's 1000W ultra quiet generator runs up to 9-10 hours per gallon, so that's a likely upgrade I'll add in the old generator compartment to run it at night, though I really wish it had an electric start so it can be programmed to come on only when needed (anyone know of a similar 1000W high-efficiency, ultra-quiet, electric-start model or a hack to modify the Yamaha?). The four SunPower 435W panels are 20% efficient and outperformed my expectations (in clear direct sunlight, two panels can often put out over 600W and I’ve seen them peak over 700W!) causing me to add an additional MidNite Classic 150 charge controller (which do need networked to each other btw, otherwise they get confused when trying to change charge stages). Though the controller is $620, it was still more cost efficient for me over wiring the bank to 24V, then adding a big (big to start generator occasionally, otherwise 12V loads are relatively small) 24V-12V step-down converter, 2kW 24V pure sine inverter, and a 120VAC->24VDC charger for emergencies. Keeping the bank at 12V allows me to still use the van's alternator to charge the bank in an emergency, which I've had to do once when it was left in a shop unexposed to sun for a week for maintenance and I forgot to turn off the marine fridge, otherwise the solenoid is always disconnected. I found the new panels for $300 each a couple hours away on Craigslist and knew this was my best shot at an air-conditioned summer. Austin, Texas has had a abnormally mild & rainy summer so far, so it hasn't been tested in 100F heat yet; I really need to add a heavy insulation blanket between the van & coach, as well as insulating the bubble skylight. I did already add insulation to most of the non-moving upper sections of the cabin windows plus the entire rear window; naturally it's coldest on the bed. Currently in the central desk/kitchen area, it’s really never cold, just cool enough to not drown in sweat, and I do run two directional fans inside 24/7 (not the roof vent fan while A.C. is on obviously). Sealing up door gaskets and vents could help too. I’ll also note that the microwave and stock electric water heater are used regularly too, but never all at the same time (I have a Prowatt 2000 inverter wired into the breaker panel). Not pictured in the photo album is the hole cut in shelf where the intake ducting is ported into the air conditioner's enclosure.
The lightly used digitally-controlled 5kbtu A.C. is rated at 490W, but it actually draws 700W running all day on any given unlevel street. I may test others to see if I have a lemon, but in reality, a couple hundred watts saved might only allow me to run it an extra half hour per day. Anyone out there know if this is a common problem? Ultimately, I’d try a 20+SEER 9kbtu mini-split A.C. with heat pump, but that’s a lot more money.
Yes, it's way over the weight capacity, especially with the 290lb WR250X plus maybe 70 lbs of steel in the hydraulic hauler; no problems so far and I’m impressed with the heavy duty rear leaf springs even without the (leaking) airbags. I baby the Rialta when driving and go slow over bumps and entrances. Like everything else, the hauler is custom built, but it operates similarly to Ultimate MX Hauler. The WR250X has a 6-speed transmission, fuel injection, a dual sport motor (not a high-maintenance racing engine), and is one of the lightest bikes I could find that had those features that can still do highway speeds. With basic upgrades, it can cruise at 90mph and get 60mpg. It's not the devilish V4 VFR I desperately miss, but it's more practical and makes parking the RV much easier without the old swivel-wheel hauler.
The waterless “composting” toilet works great and truly does not stink, only when urine isn't drained for a several days or some diarrhea nastiness is happening. I built it to save water, save trips to a dump site, and to solve the smell of my old toilet. I built it rather than buying the Nature’s Head model because I have a hard time believing that N.H. owners effortlessly aim poo through the small (3”?) diameter shoot and never have to clean poo-skids, and I wasn’t keen on paying $1000 to find out for myself. Solids are mixed with cedar or pine shavings that I get for free (anything like sawdust or coco coir would work fine too). No agitator is used; solids and shavings are deposited in a grocery bag that lines the bucket, which is simply tied and tossed when full. The urine is stealthily dumped in unoccupied areas with a valve from the 2.5 gallon container to the ground behind the curbside rear tire (just like the shower). I had to run a separate line for each the shower and urinal (not shown in the pictures). For extra measure, I do hit everything with Lysol after each use and dump bleach in the urinal periodically.
I may try to link my black and grey tanks together in the future since the black isn't being used. Anyone have tips for that? Relatively harmless grey water is simply dumped in appropriate, convenient, and unoccupied areas instead of paying dump sites, and I turned the dump outlet to face the curb so it doesn't spew out towards me.
Other mods I may look into include a Chilipad electric cooling & heating pad for the bed. My old Wave 3 heater wasn’t enough for my liking, so I traded it up for a vent-free blue flame convection heater (non-directional) with a digital thermostat and fan; though now, I may be able to run a small electric heater during winter days depending on sunlight. Any other ideas for using excess electricity? Hah, how many hours might a Bitcoin miner operate before it pays for itself? The idea of running a dehumidifier to fill the fresh tank would be awesome; the water would need filtered I imagine; please share any other thoughts. Hah, if the “HHO” electrolysis voodoo actually worked, I could maybe create my some engine fuel :-P I’ll likely be installing a subwoofer and a couple exterior speakers before long.
I'm open to any questions & comments; give me a shout if you’re ever through Austin. I’m fairly confident I own the world’s most powerful array ever installed atop a Class B, maybe even a Class C; it’s a bit silly I know, the big investment to run an air conditioner for 7 hrs/day, but I was able & excited and have fun with the experiment. Hopefully solar technology, advanced supercapacitors, lithium & aluminum-carbon batteries, and high-SEER mini-splits will all become more affordable in the coming years to expand HVAC possibilities. Also, let's hope that MIT personal climate control wristband device can work some real magic too.
Questions for you:
- Know of a similar 1000W high-efficiency, ultra-quiet, electric-start generator or a hack to modify the Yamaha to e-start?
- Do window air conditioners normally draw significantly more power than they’re rated for? Or could it be my application with the enclosure (possible heat build-up) and unlevel street parking?
- Ideas for using excess electricity?
- Hours needed for a Bitcoin miner to pay for itself?
- Know how I might link the black and grey tanks together? It’s likely simple, I just haven’t dug around yet.
- Any thoughts on using a dehumidifier to fill the fresh tank?
I have moved on to other living arrangements, but I check in here, from time to time.
All I can say is wow! Your rig looks great! Definitely an inspiration.
I stopped in Austin in my Rialta about this time last year and it was hell. I've never been so hot in my life. So I completely understand why you'd want to deck your roof out in solar panels.
It's not really feasible on the street, but I opened the canopy shade, so it'd take some of the sunlight off the RV and provide shade for the coach. Also, yes, insulating that skylight will help.
No tips about linking the tanks, except I've heard that the tanks are apparently legendarily hard to access. I contacted one company about installing my tank meter properly on the tank, and they literally refused the job because they claimed it was so difficult.
AFAIK about Bitcoin, I thought it doesn't really make sense to run your own miner these days. The compute difficulty is so high, that you'd never run a profit. But, who knows how the equation works out, when power is free...
I'm planning to be in Austin for ACL. If you'll be around, I think I owe you a beer from all the forum advice you've offered me, on here!
PS - To anyone who stumbles on this post, I'm actually selling my Rialta right now! Get in touch if you're interested!
This is a continuation of the Living in a Small RV series. It will be a bit boring for anyone who isn't interested in solar power, but I wanted to write it like this because I had a tough time finding all of this information tied together.
There are two classes of devices in an RV that need electricity, AC and DC. The DC ones run off the battery and these include things like lights, the water pump, the vent fan(s), and anything you can plug into a 12v socket.
The AC ones are primarily the air conditioner and the microwave. They get their power from either plugging the RV in to a campsite or 120v socket at a house or by running the generator.
At a recent show on small-scale power, I saw an interesting display of a domestic biogas generator, ideal for installing in suburban household. It's a good deal: garden waste in, three plate-hours of gas per day out, and it couples to the sewerage system so there's no maintenance. Good so far.
But then I asked the question, "what happens when you're not using the three hours of gas?" The answer is that excess gas simply vents into the sewers.
Now this is not a good solution. Biogas/sewer gas is methane, and although this methane gas in not a fossil fuel, it is still methane, with 25 times the global warming capacity of carbon dioxide. It is not something that is responsible to vent into the atmosphere. So on the one hand one can displace a fossil fuel with a biofuel, but the spillage of that biofuel leads to increased global warming.
Biogas is used, in places, to generate electricity. One can make money out of this, by capturing methane, say from a landfill, and burning it in an engine that spins a generator and sell the electricity and the carbon credits.
But the engine one uses to spin the generator is a heat engine, and immediately two thirds of the energy is lost as heat. Some methane now will not be vented into the atmosphere, which is good, but it does represent a lost opportunity: more fossil electricity could have been displaced by the biogas. Additionally, generators are expensive, require a lot of maintenance and are more inefficient the smaller they are. It would hardly be worth anyone's while to run one at home.