The RV of the future
Over the years, particularly after Burning Man, I've written posts about how RVs can be improved. This year I did not use an regular RV but rather a pop-up camping trailer. However, I thought it was a good time to summarize a variety of the features I think should be in every RV of the future.
Smart Power
We keep talking about smart power and smart grids but power is expensive and complex when camping, and RVs are a great place for new technologies to develop.
To begin with, an RV power system should integrate the deep cycle house batteries, a special generator/inverter system, smart appliances and even the main truck engine where possible.
Today the best small generators are inverter based. Rather than generating AC directly from an 1800rpm motor and alternator, they have a variable speed engine and produce the AC via an inverter. These are smaller, more efficient, lighter and quieter than older generators, and produce cleaner power. Today they are more expensive, but not more expensive than most RV generators. RV generators are usually sized at 3,600 to 4,000 watts in ordinary RVs -- that size dictated by the spike of starting up the air conditioner compressor when something else, like the microwave is running.
An inverter based generator combined with the RV's battery bank doesn't have to be that large. It can draw power for the surge of starting a motor from the battery. The ability to sustain 2,000 watts is probably enough, with a few other tricks. Indeed, it can provide a lot of power even with the generator off, though the generator should auto-start if the AC is to be used, or the microwave will be used for a long time.
By adding a data network, one can be much more efficient with power. For example, the microwave could just turn off briefly when the thermostat wants to start the AC's compressor, or even the fans. The microwave could also know if it's been told to cook for 30 seconds (no need to run generator) or 10 minutes (might want to start it.) It could also start the generator in advance of cooling need.
If the master computer has access to weather data, it could even decide what future power needs for heating fans and air conditioning will be, and run the generator appropriately. With a GPS database, it could even know the quiet times of the campsite it's in and respect them.
A modern RV should have all-LED lighting. Power use is so low on those that the lights become a blip in power planning. Only the microwave, AC and furnace fan would make a difference. Likewise today's TVs, laptops and media players which all draw very few watts.
A smart power system could even help plugging into shore power, particularly a standard 15a circuit. Such circuits are not enough to start many ACs, or to run the AC with anything else. With surge backup from the battery, an RV could plug into an ordinary plug and act almost like it had a high power connection.
To go further, for group camping, RVs should have the ability to form an ad-hoc power grid. This same ability is already desired in the off-grid world, so it need not be developed just for RVs. RVs able to take all sorts of input power could also eventually get smart power from RV campsites. After negotiation, a campsite might offer 500v DC at 12 amps instead of 115v AC, allowing the largest dual-AC RVs to plug into small wires.
With today's electronics, the truck engine might be usable as a main or boosting source of power. While most vehicles come with smaller alternators (80 to 100 amps) there are readily available high power alternators that can deliver 2.5kw or more. (The truck engine is capable of 100s of kw of course.) New systems developed for hybrid cars are making this technology better and cheaper. This might allow a vehicle to have an even smaller generator, and start up the truck engine at rare times for a special boost or recharge. They are getting to the point where engine start/stop is getting so efficient that hybrids stop their engines at red lights. Designed from the ground up, an RV might do fine with just the truck engine and no generator at all. It's expensive to run a truck engine at idle, and not that efficient to run it at low revs, but you need not do that with the battery, alternator and smart power controller at hand. It may even make sense to add a solar panel (though solar panels tend to be pretty wasteful on RVs since they only are used when parked and one is often parked in the shade.)
Smart power can also mean shutting down appliances when another load comes on. So if you are running the AC and somebody wants to run a hair dryer, toaster or other short term stupid load, you can shut off the AC for a few minutes. (This is similar to the idea of the microwave shutting down briefly during AC surges.) In general a smart power system would track loads and shut down lower priority loads or loads that can handle it when other power demands appear.
Now if you want to get into the appliances found in bigger RVs like washer/dryers and dishwashers, you may just have to accept they only work on a high-power connection. Though even those can be made smart. An electric clothes dryer uses a ton of power, but it can happily shut off the heater briefly. (Propane dryers might make more sense in any event.) Dishwashers and washing machines can shut off heat or even motors for short periods with little harm. If a person fires up a toaster, they might notice the dishwasher stopped but it's not a big problem. Many of these devices need not be that smart -- they can handle just losing power for a while in many cases, though the newer ones which are smart but not that smart can bet upset at this. Even though a clothes dryer might take almost all of the 30 amp circuit, if it can turn off its heater when there are other demands, it might well be able to coexist with a lot.
Cooling and Heating.
The AC is the prime method of cooling, but in the southwest, swamp coolers are much more efficient and quieter, as long as water is not in very short supply. RVs meant for that region should consider having these. All you would need would be a vertical panel, perhaps in the wall, which can have water drip over it as the air blows from the fan. These can run on 40 to 80 watts, barely needing a generator. Swamp coolers don't cool sealed vehicles very well, they are better bringing in dry outside air and cooling it to blow on you, so it does take some design of the ducting. They are no good where it's humid.
When you have an 80 gallon water tank handy, you can also do things to make cooling and heating more efficient, if people don't mind wide variations in temperature of their water.
RV fridges are no-moving-parts systems which heat ammonia water up to emit the ammonia, which then condenses and cools. So they spit out a fair bit of heat, through a vent to the outside. There should be an option to have a small fan and electronic vent so that heat can be brought into the vehicle at night when it's cold. Why waste heat?
Water tanks and pump
The plumbing in an RV is even more important than the power to many. If you go dry camping, you want large tanks for fresh water, gray water (drains) or black water (sewage.) Normally as your fresh water empties, your gray water fills up. Why not put both tanks in the same space, as rubber bladders. You could not have both full but rarely does anybody ever want to.
The gray water, by the way, can also be used as the source for water to flush the toilet. I've also seen people build (outside an RV) a recirculating shower that let you shower forever on a few gallons, but I don't know if the safety folks would ever approve that. Possibly if you had a filter and loaded the water with extra chlorine or bromine. Sure, showering in high-chlorine water isn't great but not worrying about show length can make up for that. Clean your rear out at the end and do final fresh water rinse after throwing a switch to turn off recirculation.
While there are drinking water safe rubber bladders, we should also realize that almost nobody drinks the tap water in an RV, because you never can be sure how well sanitized the water tanks are. So accept that, and put in a small drinking water system for bottled water at the sink. If it uses a bladder it can take advantage of the pressure in the main system, too. You can brush your teeth fine in the bathroom sink with the internal fresh, non-drinking water. Or you can just do like most RV people do now, and drink bottled water.
The water pumps on most RVs are too noisy. It's annoying getting up at night, and running a little water for the toilet or washing only to hear "brap-brap-brap" waking up your companions or campsite neighbours. Here an air bladder could be the answer, at least for the night. (Turns out this is available, I just haven't seen it.) For a shower, you might need the bigger water pump or a noisy air pump, but I bet we could do better on that. I should note that one value of the sound is it lets you know if you have a leak or have not turned a tap fully closed. It makes it very overt that you are running water, and that's good to be reminded of when dry camping. An alternative might be a quiet system and a smart alarm that makes a noise when you run water for too long, or if the patterns of a slow drip become apparent.
A two-bladder system for fresh/gray would make it harder to measure the levels of the tanks. That's OK because the meters they have today are usually close to useless. However, better methods are available today, such as pressure transducers (if the fresh bag is on top) or reflected light. You should not normally have to measure the gray, because it's impossible for the gray to fill up other than by draining the fresh, unless you have another source of fresh water -- which you know you can't do unless you are doing outside showers.
New ideas for the toilet are harder to come by. Some already existing -- composting and incinerating toilets, for example. I continue to push for design of more accurate sensors for the black water/sewage tank, perhaps based on pressure or something else better than the current system, which fails quickly as toilet paper gets stuck to sensors.
Toy Haulers
These days, toy haulers are becoming very popular as RVs. These are RVs built on an open plan. Beds raise up to the ceiling, couches and tables fold into the walls, and the back becomes a garage for ATVs, dirt bikes, etc. I admit I am tempted by one of these if I could find one able to hold my 17' 6" art car.. I like the open plan, though the downside is your vehicle is full when you make short stops. (One nice thing about RVs is if you find yourself stopped for some reason, you are ready for an instant picnic.) Toy Haulers tend to be designed for dry camping, with big water tanks, and lots of storage. However, you have to haul out the toys and do the setup at every place you stop, and then reverse that, unless you get a big one with a dedicated bedroom.
Toy Haulers could make use of all the above ideas, except connection to the motorhome engine. (It's possible one could design a way to connect a tow vehicle and the trailer able to send 1kw or more but not too likely.)
For big trailers, which have electric brakes, it might be possible to make them easier to drive (and particularly easier to back up) with smart computer control of the brakes to torque-steer the trailer. For novices, backing up with a trailer is hard. I saw one system that showed you the trailer's path based on current wheel condition on your backup camera, which is a great idea.
Comments
Ronald Pottol
Sun, 2013-09-15 18:31
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RV issues
One thing you missed is that RVs have lead acid batteries, which are quite wasteful, in many senses. They are heavy, and you can use only 25% of capacity on a daily basis, 50% on a weekly or less, if you want them to last a good number of years, and they need to be kept fully charged. Some people are moving to other stuff, http://www.technomadia.com/lithium/ for people who are using LiFePO4 batteries, they are much lighter, you can use 80% of your capacity, and can be charged much faster (usually, even a huge battery pack in an RV can be charged only slowly, that 200Ah (at 12v) can only take 600 watts charging, and to really fully charge it, you need to keep hammering on it after it is mostly full for at least an hour.
The other factor is how much of the market is willing to pay for this stuff? The people who use their RV 6 times a year, and plug into a full service camp is a big chunk of the non toy hauler market, and none of this is a win for them. For the full timers, sure, and for the dry camping regulars, who are off many times a year, somewhat of a win. But the people who can see up front that this is worth it to them is small.
For the use of multiple power inputs, have a look at http://www.emarineinc.com/products/Magnum-MSH3012M-3000W-12V-Pure-Sine-Wave-Inverter.html will let you combine shore/generator power with your batteries (or solar) to meet your power needs, and let you do things like use that puny 15A circuit. So there is some progress being made.
brad
Mon, 2013-09-16 01:38
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Better batteries
Yes, no reason that you can't use better batteries. But lead acid is not so bad as you say, it actually can have a pretty long life if well maintained. And lead acid batteries are one of the most recycled things in the world. They do weigh more, and I don't know if anybody has done an analysis on the fuel cost of that weight and what it means to use a lighter, more expensive battery.
This will actually be cheaper. The RV already usually has about 250ah of battery in it, and the old-style generator costs $4,000 or so. The smaller generator with new electronics should actually cost less and give all these benefits. And use less fuel and be quieter. The ability to run the RV with AC off a 15a circuit also means not installing a 30a line at the house if you want to use it there.
Arthur Tyde
Sun, 2013-09-15 18:51
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Great idea - some comments...
Dumping excess heat into the cabin from a RV fridge is a interesting thought. However, these units are usually running on 12 VDC and propane. An interesting idea however - and if the fridge makers were able to separate the heating system from the exchange... :) I built a duct through the underside of my trailer for towing in sub zero weather. It routes the truck exhaust through pipes that run along side the water pipes and between the black, gray and fresh water tanks. Keeps the toilet from turning into a giant ice cube while on the road. It vents out the back of the trailer through a standard exhaust pipe. The problem with trailers - is that most are crap, even the best. So adding floor insulation and sealing the undercarriage with sheet metal is a very worthwhile project as it protects the plumbing and wiring harnesses from road junk, salt, bits of metal and such.
Warm White LED's are indeed critical. You can light your entire rig - it'll be brighter, and you can leave all the lights on all night long - and it'll use less power than two standard 12V incandescent bulbs. I do keep incandescent bulbs in my reading lights though... reading by LED bulb is just plain uncivilized! :)
My Playa fridge mod was to install 3 muffin fans under the fridge vent on the top of the trailer. On very hot days - I run the fans, which turbocharges the fridge and freezer by moving air across the heat exchanger - you can make hard ice on the hottest days very quickly.
In my unit, I have 500W of solar and an APC UPS acting as the inverter. The systems are integrated such that the house can run from the UPS bank (while solar is topping off the house) and the UPS can run off the house bank when solar is charging the UPS. The net is non-stop redundant power.
There is a company that makes a RV swamp cooler - http://www.turbokool.com/ very expensive... :( A friend of mine built a 24V based solar charged 4000W inverter system with a huge bank of batteries. Claims it runs his AC all day long and new panels are efficient enough to not only charge the system - but (on a sunny day) power it (with a small battery hit when the compressor kicks on). A good option for a large motorhome with plenty of roof real estate (and a commercial frame).
There are pressure tanks you can add to the RV water system to even out the pump cycle problem.
My RV has a home brew temperature controlled shower. You key in the temp you want your shower to be and turn it on. It adjusts the hot and cold intake to match the temp request (it re-circulates the water back into the fresh water tank until ready) and then switches to the shower hose / head. Perfect shower every time - even has a pause button so you can rinse, pause, soap up, and rinse - saving even more water.
For Fresh Water - there is a small 5 gal tank under the sink (actually, a place to slot in a Calistoga drinking water bottle). The sink in my RV has a hole for one of those filtered water spigots. I just ran a line to a pump that snaps onto the top of any 5 Gal fresh water jug.
What I love about being an RV enthusiast is the creative side of hacking survival systems. I could easily go 3 weeks in my rig completely off the grid. By using a spray bottle to flush the toilet, being smart about dish use (and menu planning), a high pressure (low flow) shower head - you can make a 50 gallon tank last a long long time with little compromise in comfort. Power these days is just getting easier and easier to solve. However, the ONLY inverter generators I have seen last more than one trip to the Playa are Honda and Yamaha models - you very much get what you pay for in that department.
Finally - my best RV playa cleaning tip! The leaf blower. Lock everything down or take it out - open all the windows and doors - turn on all vent fans and hit the inside of your rig with any decent Black & Decker electric leaf blower. After the initial * POOF * (when all the hidden playa dust goes airborne) the fans will suck most of it out of the RV.
brad
Mon, 2013-09-16 01:45
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Solar, and lasting a while
Solar tends not to be very cost effective for camping. You have to park in the sun (which means more cooling load) and your panels are flat, unless you can tilt them to the sun. Once the batteries are not low, you throw away all the solar power. When not camping you throw it all away unless you somehow connect the panels to a grid system when parked. Gasoline generation can be greener than solar if the unit is not used a lot.
Some fridges can run on 12v but this is very rare, and will drain most 12v battery systems pretty fast. In the popup camper we used, the fridge could run on 12v mainly so you could power it while towing it. In this case, the power is coming from the tow vehicle over the lighting plug, which fortunately can deliver a fair number of amps. Then the power is coming from the tow vehicle alternator. That's because you tend to not want the propane on when towing these puppies. Even with big motorhomes, which will run the fridge on propane while driving, they want you to turn it off every time you fill up, etc.
3 weeks on 50 gallons is pretty impressive though. I hate the standard showerheads in RVs -- some people replace with sink squirter hoses and they are much nicer.
More than the leaf blower is the air compressor. It gets playa dust out of many things. And the shop-vac with drywall bag.
And for the poster below: Swamp coolers to cool a whole rig would indeed use a lot of water, though there are campsites with plentiful water and no electricity. But the way to use a swamp cooler is not to cool the rig, but to point it at the people, so you want a vent blowing on the bed, or a vent blowing on the seats in the living area.
Hal
Sun, 2013-09-15 19:21
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Trace (later Xantrex) built
Trace (later Xantrex) built an inverter that would load share just as the new Magnum inverter does but did it 15+ years ago. They built them in 2500 watt, 12 volt as well as 4000 watt units @ 24 volts which were designed for the RV industry. They also had off grid units with higher capacities. Some of the people @ Magnum actually worked at and helped design the old Trace units.
As to the tank sensors, there are pressure sensors today that do work well and at least one system that reads from outside non metal tanks that are accurate to within one percent.
Although evap coolers sound good, the water required really makes them a tough nut for RV use in anything much larger than a pickup camper. You can easily use 6 gallons an hour or more to cool a 30' rig. Ok if you have hookups but dry camping would require a lot more than my 200 gal capacity.
futureboy
Wed, 2014-11-26 15:42
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is anyone doing this?
Hi there, I just stumbled on this post as I've been googling for futuristic RV's. I am part of a small but growing group of people in the US that wants to live in tiny home, and in my case an RV. I've been doing some research into RV's and I agree with a lot of what you said. It seems that most RV's even nowadays are only designed by retired guys in their 70's, and that's fine but I think we may benefit from someone in their 20's or 30's taking a fresh look at the RV with a lens of a full time mobile home for two environmentally-friendly people and possibly a dog. The dog likes earth too.
Anyway I wonder why nobody has thought of rebooting the RV into the 21st century instead of the annual cranks of the same decade-old design. I see concept photos on pinterest, but nobody actually building them. How great would it be to have a modern RV that has a data network for all components on-board? It would be great having a modern, hackable Android tablet that runs the entire vehicle, including things like turning off appliances or adjusting the LED lights, which by the way should be totally programmable. Maybe skip the use of keys entirely and have a TouchID sensor to start up the vehicle? I think diesel engines would be best for now since you can run biodiesel and even hemp biofuel in them, and with the legalization of cannabis the nation is also (finally) re-legalizing hemp which can make a very compelling earth-friendly fuel option.
The entire vehicle should have a powerful battery, perhaps Lithium-Ion but we will need to wait for a few things to arrive: Tesla's gigafactory, the recent Stanford battery breakthrough that may expand capacity of lithium-ion batteries by 3-4x, and some of the other recent advances that should allow these batteries to recharge 10,000+ times. There's yet another battery breakthrough that will charge your cellphone up to 90% within a minute, and theoretically an electric car within 5 minutes. Toss in the most advanced solar panels on the roof, and the combined result is a mobile home that can completely run on solar power -- perhaps not for long hauls, but in a steady state with mindful (or computer-mindful) power consumption.
I also like the idea of ad-hoc power networking between vehicles.
Basically I think a truly wonderful mobile home should be designed like a starship of the future. The computer controls everything and is smart enough to prevent bad things from happening, but not so smart that it shoots you out the air lock.
I think the fundamental problems here are numerous:
1) RV's are historically considered just that: a recreational vehicle. They are toys that you take on your week-long vacation, or occasionally for those weekend trips to the lake to fish. They aren't considered a 'mobile home' for that growing tiny home movement.
2) RV's were designed by older people who don't care about modern technology as much as we do, nor do they care as much about being friendly to the planet as much.
3) When recessions hit, RV's are the first to go. A lot of RV companies have gone out of business. I imagine it's a tough business to be in, but especially when most people don't consider your product part of their lives.
4) RV's are EXPENSIVE! I was looking at new RV's that were up to $250K. The whole purpose of the 'tiny home' movement is to not spend so much money for your home. The goal should be more like $100-150K for a brand new RV with all of the best technology. Maybe $200K for some serious luxury, but the bread and butter should be more like $100K where used RV's can be acquired for ~$50K.
The problem with building any new class of vehicle is that it's outrageously expensive to product a brand new vehicle from scratch, so the more realistic vision here is passionate individuals who start buying older, used RV's, gut them and reboot them to their liking: LED lights, networking, smart computer controls, advanced security systems. All sorts of great ideas but until a sufficiently large portion of the population is demanding more tiny homes, I think this will have to remain a niche for a while.
What we really need is someone from Silicon Valley to take some of these ideas and put them together into a new
futureboy
Wed, 2014-11-26 17:27
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another idea...
The data network could be so key. The master computer could shut down unnecessary systems as power/fuel run low, and it would allow your RV to be completely modular and expandable.
If you are living in a future 5-10 years out, living in a 100% electric vehicle (with solar supplemental power), using the latest in battery technology, if you are driving and start running low on power (say below 30%), the MC could detect that other devices are running and can automatically shut down power to non-essential devices. Once you drop below 10% it would shut down power to literally everything except propulsion and the nav computer. At 5% it would start to slow down the vehicle and force you to sort it out, pointing out the nearest charging station on the screen.
And of course small Android tablets around the vehicle could interact with the MC. VERY Star Trek!
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