True, but once it’s chilled, the power consumption would be less than if the water wasn’t there. While it’s counter-intuitive, it takes less energy to keep a full refrigerator cold than a nearly empty one.
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“Real” full-size solar panels seem to run about $1/watt these days, not including shipping:
http://www.wholesalesolar.com/solar-panels
They’re much bulkier, but maybe more the size you’d want for this system.
If you’re doing a lot of driving, I wonder if it might make more sense to set up a charging circuit from your alternator. Include some sort of current limiting (and a switch) so that you’re not pulling too much power from the other vehicle circuits.
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The flywheel effect of thermal mass is counter-intuitive?
No criticism, just surprised. I already knew a lot of stuff I take for granted from long familiarity isn’t obvious to everyone, but I wasn’t expecting that one.
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No experience with them, but generally speaking diesels like to run, and don’t like sitting about waiting for action. You have to guard the fuel against algae and water buildup, and the outfits I know of that use diesel power backup for data centers run them at least once a month, and do yearly PM.
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Typical home standby generators, whatever the fuel, usually automatically cycle through that. Every 30 days they’ll kick themselves on and run for around 30 minutes. Though I have no clue if that’s built into these (or any other) generator or if its something established with the set up. Most people I know with them have a company contracted to service them once to twice a year, and fuel get’s checked regularly. Though nothing prevents you from doing it yourself. Though from what I understand the propane ones are generally considered a better choice.
Can’t speak to Hyundai. I know their cars aren’t known for their longevity. But that’s mostly everything but the engines. Every single generator owned by every single person I know is a Honda. Including an increasing number of these. Which are awesomely useful little bastards.
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I cannot comment on this exact panel, so you may discount anything I have to say… I have found, however, that these little panels just haven’t helped me at all. Trickle trickle trickle.
For just a bit more money (okay 50% - 100%) I would urge you to get an 800 or 1000w generator. Generac is fine. (Or you can pay $700 for the Yamaha.) These small generators use so little fuel, and are useful for so many other things. My two cents from being stranded in vehicles far, far from home with needs for electricity.
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Yes, freezing freeze-able stuff pre-trip works really well.
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Likely. The alternator is already charging the house and the starting battery. There is a relay to ensure the starting battery is at a good charge before the house gets juice and to stop the house battery from draining the starting battery. I don’t want to start cutting the van to get in a bigger battery tho.
Starting inland at the hot springs and moving to the coast after a few days on the next trip. I’m also planning to return to the whales this spring, and that’ll likely involve lots of beach camping on the pacific and the gulf of CA. I really enjoyed Bahia de Los Angeles.
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You know what. Now that I think about it you’re probably correct. My folks (and Aunts and Uncles) do a lot of serious off the grid beach camping in large trailers. My father is in process of adding solar panels to his. So far as I’m aware the solar panels don’t generate enough power, even with the serious roof space of a 45 foot camper, to fully charge the batteries in a reasonable amount of time. That’s accomplished with a power hook up at home (or at a on grid slip at a campground). Full charges on the road are done with a single 1600w portable inverted/generator, though two are kept on hand for running in sequence or trading off duties and redundancy. They only hold like a 1/2 gallon to a gallon of gas, and can run for hours without going dry. Charge the expanded bank of RV batteries in an hour or so. And provide enough power to run the full complement of circuits on the camper. The solar panels are all about extending the capacities of the batteries. Trickle charging while you run off the batteries so you don’t need a full charge or a top up as often. Supposedly Dad’ll get 5 days out of a full charge as opposed to the current 2-3.
@jlw is working with a much smaller system. Just one battery as opposed to 12. But then you’ve also got the constant draw of the refrigerator (the camper fridge is propane, unless its connected to a power hookup where it switches to electric). Might be better going with a small inverter/generator to full charge/top up, and to run the fridge when chilling down. And an extra battery and larger solar panels to get more time off those batteries when not running the generator. From what I understand that’s sort of the stock set up for these situations, but again the fridge isn’t usually one of the things that runs off battery power.
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Yes, to us mere mortals, it is. That’s why this exists. And this. And all of these.
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It doesn’t seem likely to me either that you will get anywhere near 80w continuous out of these.
I notice you are looking at a $750 electric fridge so this is not a budget setup. I’d just go with a conventional cooler like the Coleman Ultra Extreme, which in my experience can easily last 3-4 days in the shade if you do things right with ice blocks and NOT draining water. You could get a ~75 quart cooler for less than $100 which lets you put in massive amounts of ice blocks (or frozen water bottles) and still fit in the food that you would get in your 37 quart cooler. Then use the remaining $650 to hire people to deliver ice to you.
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And natgas (methane) is even better, if you’ve got a reliable supply.
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Pack some beans.
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I have a portable Honda, actually several of their small engine powered things around the place, but I wouldn’t buy anything Diesel from them.
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I’m a long time camper van owner, and I’ve made a ton of mistakes with solar over the years, and I’ve found that a biggie to avoid is the non permanent fold up type. They’re a hassle to set up, so after awhile you tend not to. And besides its super easy to just install a panel on the roof.
Another factor with that panel is that its 12 volts, which is pretty antiquated now that we’re in the era of cheap high quality MPPT charge controllers, that let you use higher voltage panels with a 12 volt battery setup. If you haven’t wrapped your head around the difference between MPPT and PWM charge controllers, its worth doing, and don’t believe anyone who tells you that PWM controllers are just fine.
In a nutshell, an MPPT (“Maximum Power Point Tracking”) controller will find the strongest voltage that the panel is outputting and use Ohm’s laws to increase the wattage while decreasing the voltage until the voltage is a usable ~14 volts or whatever. That means you can use higher voltage panels, and that even when there’s little sun you’re getting usable power from it. PWM, on the other hand, simply flashes the power on and off to prevent over charging your battery. Modern MPPT controllers have much more sophisticated charging circuits, so they not only get more power from your panels but use it better.
And remember that no solar panel gives its full rated output, so that 80 watt panel will probably put out a max of 50 watts at high noon, especially by the time the power reaches your battery.
If I were you I’d take a serious look at high powered (260 to 320 watt), high voltage (36 to 46 volt) frameless panel, which are super light and won’t affect your pop top’s ability to pop, and they’re low profile so they’re hardly noticeable from outside. They’re cheap too, I’ve seen them come up for $60 on Craigslist. If you’re interested but can’t find anything PM me, there’s a guy in the south bay who I’ve bought a few panels from who always seems to have something for sale cheap.
After that you’ll never have to worry about power again, assuming your batteries are decent, and you won’t damage your batteries by going too low at night, which you’re probably doing if your camper doesn’t have solar currently. And you won’t have to go through the ritual of unpacking your solar panel every time you camp.
These Tracer MPPT controllers are awesome. I have and love this one:
Its great but a bit large, and I know in a Westy space is tight. It probably has more power capacity than you need, so if you want to save some space you could get away with the 20 amp version. But note that you can mount it in some deep corner that you don’t have to access very often since it has a handy remote monitoring box.
And don’t scrimp on the wires, get at least 12 gauge, maybe 10. This works well and has the connectors:
One interesting thing about the Tracer charge controllers (and others in their class) is that they send their status as serial data, which that remote monitor box is reading. There’s tutorials out there to read the data from a Raspberry Pi, so my fantasy is to make a script that will flip a relay if the solar panel is putting out enough watts, so it’ll power my propane fridge with AC power. When the watts dip back below the threshhold it turns off the power so the fridge will kick over to propane. Most RV fridges have an “auto” setting that will do exactly that, so all that’s required is the Pi brain part.
On a sidenote, my favorite van lighting at the moment is these guys:
Low power and look awesome, and powered by 5v USB, so plug them into a cellphone charge pack and light up your camp. There’s also 12 volt versions if you want to permanently mount them inside your van, but its kind of fun to be able to string them in different configurations, and of course you can plug them in wherever you charge your phone. I probably have 5 of them at this point (some red some warm white) and use them all constantly. They’d look great in a pop top.
Anyway, hopefully something in there is useful, and have a frickin awesome trip! Eat a fish taco for me!
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I doubt they even make one. They only seem to have launched a diesel engine for cars for the first time a few years back.
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Hyundai is* one of the sprawling chaebols, cars are not the only product class. See e.g. the here.
* was? iirc they split up in a handful of (more or less) independent companies
eta: blargh, you were talking about diesel generators. sorry.
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It is indeed counter-intuitive. In the best case it should take exactly the same amount, because the walls (through which heat gain takes place) are at the same temperature and you can regard them as a black box.
What is true is that an empty refrigerator gains heat faster with the door open, simply because there is more cold air circulation.
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Exactly. Neither Honda nor Toyota invested in Diesel technology, which is why I wouldn’t buy a Diesel generator from either.
You know how he does it right?
He focuses his psionic power on an infinitesimally small 5-dimensional hypersurface for a period of local time of duration less-than 1 Planck-time.
Unobtanium, man.
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