In looking at refrigerators out there that are all electric, I see some 12v models. Outside of the price differences, is a 12v going to be more efficient as a 120v that is running on an inverter? Do the 12v models work as well???
You are, of course, aware that the inefficiencies in inverters will consume some percentage of the electricity and blow it off in heat. I'm reminded of this every time I open my electrical bay while my air conditioning is running. So for sure you're losing some efficiency when you use an AC fridge.
This is all theoretical, so don't take this as imperical proof for every comparison. There are at least three major components to a refrigeration system that effect it's performance/efficiency:
* Insulation
* Compressor
* Refrigerant
For a DC powered refrigerator though, you're generally gaining back more than just the inversion losses. Most DC refrigerators that I investigated had quite a bit more insulation than an equivelant AC powered fridge. I can only guess that, because these are typically used in off-grid applications, the manufacturer is trying to boost their spec. sheet numbers as much as possible. Of course the trade-off is decreased usable CU inches.
The DC powered fridges also typically have another advantage in that they use variable speed compressors (see Danfoss compressors) that allow the controller logic to ramp up/down the refrigerant circulation in a more efficient manner. Modern mini-splits also use variable speed, scroll type compressors to reduce start-up amp spikes. AC fridge compressors are usually just on/off.
In my research, the refrigerant tends to be the same between AC and DC fridges (R134a).
At the end of the day we decided to just buy a simple Lowe's AC refrigerator because of cost. An equivelant number of CU inches in a DC fridge is about double the money of an AC fridge. This also gave us a wider range of fridges to choose from since DC fridge models/manufacturers are far fewer. I plan on having ample solar power on the bus, so I'm not really worried about the inversion/compressor loses. Last I checked, after initial cooldown, I could run our fridge for at least 24 hours on the battery without any input.
If you found an extremely efficient 120v fridge that can run on 1 amp @ 120vac, that would still require over 10 amps @ 12vdc. Plus any extra for the inverter loss.
We had a 12vdc fridge (Vitrifrigo) in our bus. It ran directly from 12vdc and consumed about 6 amps from the batteries when it was running - it had about a 50% duty cycle once cooled down.
How well do the 12vdc fridges work? If you eliminate the low-end models (which won't work well/for long regardless of the power source) they work extremely well. Our Vitrifrigo would be at temp within an hour or two at most, and it would keep out ice cream hard enough that it was very difficult to scoop. Never had milk go bad or any problems with the temp regulation.
There are things you can do to help any compressor fridge work well, like ensuring adequate ventilation and adding pancake fans to the compressor coils to boost the ability to shed the heat.
Like already mentioned, these 12vdc fridges were initially designed for use in the marine world and are very well insulated. They are also intended for use in vehicles and can withstand being on the road. A residential fridge may or may not like being inside a rolling earthquake.
In the end though, it's all going to come down to a few factors...how big is your battery bank, how fond are you of running the generator when necessary to recharge them, how long you plan to be off grid, and what your budget is.
If you have solar on the roof then go ahead and put whatever fridge you like. As long as you have more solar output then your constant loads you can run what you want. Otherwise, do the math on the energy use and figure out what works best for you.
I have 400 watts of solar on the roof,, and a 4X6V battery bank.. When my RV type fridg. crapped out I went looking for a residential fridg. that would fit in the hole and be efficient on 120 inverted power.. I found it in a Frigidaire energy star rated 1 amp that was twice the inside voluum of the old one and would fit perfectly.. It has been one year ago and I couldn't be happier,, all this on less then half the cost to replace the previous one..>>>Dan ( I also have a 3000 watt PSW inverter.)
Be careful with small 120v fridges some tell you they cannot be built and will not work over a 100 degrees.We install one from H/D in Tom Caffery's 4106 GM lol we both said he was better off with his old propane fridge from the 70's ,I have nothing against the propane fridges except for the price
I just replaced the frig in my little bus with a Frigidare 1 amp 120v standard compressor. It uses R 600 as the coolant (which is flammable under the "right" conditions) but WAY better than R 134 or R12 just as they advertised it would be. My old frig (134) took overnight to cool the box and then ran about 60% of the time. The new frig was down to 40 degrees in less than an hour and cycles at about 30%--and it is so quiet I have to put my hand on it to make sure it is running. The old frig is 20 years old and used when I got it but it is still running. I won't live another 20 years so I won't be around to report--unless the new frig craps out way sooner. Jack
If you plan on having an off-grid sized solarbattery setup, then an AC 10-11 sqft is a go to refrig. Efficient ones run around 600 watts per day, inverter runs 24x7, Starlink uses more than refrig, big deal. From all the reports, if properly mounted and secured, an ac unit lasts fine.
I have a total electric coach with 21 cf side by side counter depth fridge that has the energy star rating and it is a energy hog for a 3 amp rated fridge
We love our LP/120V absorption RV fridge. Also run a 12V/120V chest fridge/freezer that 400W solar keeps up with.
current travel trailer uses Norcold 110/ propane. Always ice cold no matter when outside temps over 100 degrees. The 12 volt/ 110 Norcold could NEVER provide that performance in hot weather.
I think the choice should largely depend on your power source. If you are mostly connected to the grid 110v is the obvious choice. If you have solar power either of the electric options can be good ones. In my case I have onboard propane for the range and the generator anyway so a propane fridge makes the most sense as it's appetite is minuscule compared to the genset and won't even be noticed.
Jim
In our lifelong experience with RV absorption fridges the LP mode cools the most efficiently. A simple addition on the back of an absorption fridge is a small computer fan that blows up through the upper hot coil of the fridge. We only use it in temps around a 100°F it really helps the cooling unit when it taxed with high heat. Fwiw.
The absorption style on propane does use fuel. Just want to clarify that because mine was using about a tank a week and nearly it all was the refrigerator. the stove is propane but it runs for months on a tank.
I have a replacement flame pilot and the old one may have consumed excessive fuel. It's getting installed in a couple weeks but hartd to judge if it improves fuel use until some time passes.
Never know, the consumption drops a lot, I might keep the old one in a bit longer. lol
Quote from: windtrader on August 23, 2022, 01:13:26 PM
The absorption style on propane does use fuel. Just want to clarify that because mine was using about a tank a week and nearly it all was the refrigerator. the stove is propane but it runs for months on a tank.
I have a replacement flame pilot and the old one may have consumed excessive fuel. It's getting installed in a couple weeks but hartd to judge if it improves fuel use until some time passes.
Never know, the consumption drops a lot, I might keep the old one in a bit longer. lol
All the absorption fridges I ever owned used about a gal a week,could be the t stat is letting the flame burn all the time ,water heaters will suck up some propane in hurry
I understand all the people that love this solar thing, but I guess I just hope we all like what we have. We are used to being able to run the fridge on propane and there is a 35 gallon propane tank buried in the belly of the bus behind panels. And call me dangerous but we still run the fridge on propane going down the road like we did with our 3 previous RVs. The bus has a 35 gallon propane tank and I have the tank and valve checked once a year. But we think it is made to do what we are doing with it.
We only have 6 bay doors in the shorty. One is monster Kubota Gen that I can work on, it is pretty quiet, and it is already there. I like it, it works great, and all the wiring is set up to be happy getting juice from it.
I don't know how many batteries it takes to store the juice from a roof full of panels, but I suspect it is more than our little house battery bay wants to hold. I have not looked at cost for panels and battery bank I guess because we don't think we want to go that route.
Again there are so many options and I just hope people like what they have. We like our generator and our fridge that is propane or electric. Rita likes the gas range. We have a 200 gal fuel tank so thinking we could boondock with non stop cloudy days until we run out of water. We are just so content with how well all of it works. I don't want to start tearing into the bus to jerk out the generator, the propane tank, and drill holes in the roof.
I am not saying it is better. Just better for us. I would sing a different tune if we were full timing, but not doing that again. We like to take trips, but like having a house.
However, it is always fun going to bus gatherings to see all the different systems people have. Especially the ones they came up with on their own! All part of the "BCM" thing where individuals convert these things in so many different ways.
Ted - point well taken and there what is best for one is not for another. Like your case 33 gallon propane tank. I have two of the little ones and seems like every couple weeks having to fill them up. batteries work better for me. My main point on propane is it consumes a fair bit of energy. Clifford says a gallon a week, mine seems more. Either way, that is a huge amount of stored energy. Enjoy the ride!
For several plus decades our converted bus was & still is primarily LP & 12 VDC. We like quiet boon docking and LP enables that completely. We carry four 30 LB bottles which lasts for months. They're all portable so usually refill in pairs with the toad. The best thing about the far NW is no need for air conditioners & that in itself is truly a game changer. Between the recent upgrades of inverter and supplemental solar we barely log hrs on the genny. 8-1/2 hours on it since April & that was to get out of the southern states. We've always run LP in all our campers while underway. No more dangerous than lithium banks IMO. We run all WLA batteries anyway all our wallent wants to shell for.. Different strokes for different folks but the term Bus Nuts is our common ground and unique. Yep Enjoy the ride...
Quote from: windtrader on August 23, 2022, 07:54:37 PM
Ted - point well taken and there what is best for one is not for another. Like your case 33 gallon propane tank. I have two of the little ones and seems like every couple weeks having to fill them up. batteries work better for me. My main point on propane is it consumes a fair bit of energy. Clifford says a gallon a week, mine seems more. Either way, that is a huge amount of stored energy. Enjoy the ride!
Do have the tanks filled or exchange the tanks ? if you exchange, they screw you paying for 5 gals and only get 4 gals
Quote from: luvrbus on August 23, 2022, 08:25:27 PM
Do have the tanks filled or exchange the tanks ? if you exchange, they screw you paying for 5 gals and only get 4 gals
I'm a cheap bastard so I get your point. What works for me is swapping at Walmart usually. the price is so little. I run my down fully, then grab a new one out the rack. Prices change but it has been hard to beat the price and convenience.
The advantage of filling your own is you pay for what it takes. Half tank full, only need a couple gallons. the main factor is price per gallon and that can vary quite a bit. Generally, at best taking empty tank then full by the meter comes out about the same or near enough it's just a lot easier to exchange at WM, no need to hunt around and get on a regular wally run.
I ran a search on ebay for over a year and finally came up with a 50 gallon Manchester horizontal propane tank that fits in one side of my genny bay. It's roughly 2ft by 32" long so it just barely tucks in to the front of the bay between the door and my front leveling jack. (which is centered) With that kind of capacity I'm hoping that refill intervals are going to be stretched out to seasonal or better. Conceivably even annual and that's if we use it a lot. I think I can live with that, especially since with that much capacity the propane guys will deliver. I can have them top off the RV when they come to fill the tank for my shop for instance. The bite is bigger of course but it's about like buying a couple tanks of gas for the toad. Or the season's fuel for the lawn mower. Just one of those things.
I think solar's a great idea but I'm not going to do a halfway job. If and when I might go that route I'll want to paper the entire top of the bus and maybe an awning besides. So it isn't going to happen until good flexible cells come to market and for me that day could well be never. In the meantime I'm pretty happy with conventional.
Jim
Thanks everyone for the numerous and informative information. I think I'll look into the Frigidaire 1 amp unit. I have a 10 cf Magic Chef in my old bus that works well. I bought one for my travel trailer too, as I didn't want to spend $2000 on a replacement LP model for that. Since we only plug into a park with the travel trailer, we get it cold at home, stuff it full of cold food, drive however far to the chosen RV park, then plug it in. I stays cool long enough for the trip and works well once we get there. For the bus, I'm not afraid of using propane while driving, as I would assume that the factory RVs are intended to run that way. When I was a contractor, I installed hundreds of LP appliances in homes, and I have had them in previous buses and RVs. I'm looking for practical convenience and price too, but I really want what works well, and gives the most options for both boondocking and plugging in (in other words, I really don't have a plan for how I intend to use the bus!!!). I think it comes down to 110 electric, since I am doing a bunch of solar panels and batteries/inverters anyway. Thanks again everyone.
Glenn - personally, i don't worry about the propane running the refrig while on the road. That'll be a thing of the past once going to AC only unit but it is an issue for some.
I really paid through the nose refilling propane bbq tanks in Canada at two locations. little over 25 bucks a tank at Canadian tire and a Uhaul. Used to paying about 13 bucks in the lower 48.
It drives me nuts sometimes on the Oregon and Texas coast when a total electric coach with solar panels covering the roof running the generator all day and 1/2 the night charging his battery bank when it is overcast and raining for 2 days.I probably run my generator less than they do because I don't let by AGM's get low 2 hours a day and I am good
We have a 10.7 CF Whirlpool WRT111SFDM refrigerator.
We have had this refrigerator in the Bus for 5 years, has worked perfectly, most importantly the wife really likes it.
Measured with my clamp meter the refrigerator uses approx. 1 amp, 120 volt when running (3000 watt AIMS inverter), this translates to around 5.5 amps, 24 volts.
On our 604 AH, 24-volt LiFEPO4 battery pack we could run this refrigerator for days without recharging.
With 1500 watts of Solar Panels, running the refrigerator and other household items, lights, TV, microwave, charge phones, on a normal sunny day the Battery pack is completely recharged by 9:30 - 10:00 am.
We run the refrigerator off the batteries while driving without issue.
If you take the doors off, it will fit easily through the door on an MCI 96A3.
Peter
Not all RV owners can afford batteries at 1000 bucks a pop either for the lpo4 batteries
Quote from: luvrbus on August 24, 2022, 06:09:26 PM
It drives me nuts sometimes on the Oregon and Texas coast when a total electric coach with solar panels covering the roof running the generator all day and 1/2 the night charging his battery bank when it is overcast and raining for 2 days.I probably run my generator less than they do because I don't let by AGM's get low 2 hours a day and I am good
You totally have a valid point.Solar works great when it shines and really sucks when it doesn't. For the first time, I had to cheat and run the genny to put some juice in the batteries. If you are not running the AC, then it can charge up pretty fast depending on your equipment and usage pattern.
Without AC, I draw about 3-4 kW, so it takes only an hour or two to charge the battery bank for the next day. I can go a few days wioth no sun but then it takes longer to do a full charge. Not a big deal based on where I stay. Cloudy days are a drag too, btw, rain not needed to put solar output in the dumps
On both my bus and truck conversion, I use the Nova Kool 9cu/ft refrigerator that has a compressor. When the refrigerator is at 35, the freezer will be at about 15 (freezer has it's own evaporator). Nova Kool makes a double compressor 9cu/ft that takes care of the warmish freezer, but is almost twice the money.
We also have a Iceco double compartment chest freezer that can have two different temperatures, but we usually keep the entire thing at 0 which does keep ice cream hard (very important). Both only take 5.5 amps when running at 12v and both have build in inverters for running on 120vac. They are very quiet running. Good Luck, TomC
My neighbor that just left to go to his new home in Wyoming left me his leased 250 gallon Propane tank with 40% still in it. I offered to pay him for it and he said don't worry just change it over to you guys. So it is not due for lease payment until Oct and that is 50.00 a year and they come out and fill it. Win Win for this winter.
:^
My neighbor in Alaska years back loved new things. He came home one day with the "Newest Thing". It was a dish that lets you get more TV channels! I helped him for a whole day setting the thing up. We have all seen them. About 8 feet across and once assembled it looked like it could track the Space Shuttle.
The dish attached to the corner of my house now is smaller than a trash can lid and we get.....hell I don't even know how many channels.
Remembering that got me wondering how soon before solar panels will evolve to where maybe one does what it takes 8 to do now? I am still sticking with what I have, but I heard today California is mandating "no petrol" cars be sold after 2035. Its coming. I guess I better warm up to electric things. Glad I will be 79 by then and perhaps ready to part with our beloved 35 foot asphalt annihilator. That is assuming we can still purchase diesel....
Don't worry-Diesels move the world. Without Diesels, the World stops. Diesel fuel will be around for at least another 100 years, if not longer. Good Luck, TomC
🎶" In the year 2525 if man is still alive🎶.... 😬
Quote from: TomC on August 27, 2022, 09:33:57 PM
Don't worry-Diesels move the world. Without Diesels, the World stops. ...
For now.
There was a time before Diesel, and there will be a time after it.
So when do we see a coast-to-coast electric semi?
Will the first one have any actual hauling capacity after the batteries are on board?
Inquiring minds want to know...
Jim
Our neighbor has a friend from Miami that just brought his Tesla up here. Around Ocala Fla he stopped to jam up the battery. Had to wait 1 hour to use the portal. 45 minutes to get it to 100%. He got here on 38% of power left. Plugged into their 110 garage outlet, all night, he was at 70% at nine the next morning.
I understand the CO2 thing and the pressure the senior leaders are under to "Do SOMETHING!". But I don't think we are there yet. Sorry if I caused thread drift....
This does not really apply to our DD world. At least for now.
Think happy Ted. Think Nappanee end of September! Just deciding as I head north on I-75 if I go around the left side of Cincinnati and stay on the interstate around Indy, or cut north just after Cincinnati??
The big rig truck manufacturers have got to get together and decide on one type of universal battery pack. Just as electric fork lifts have exchangeable battery packs, big rigs should have them too. So when a truck comes into a truck stop, the battery pack can be exchanged for a fully charged one in a matter of minutes instead of waiting hours to recharge. Just my opinion. Good Luck, TomC
Like swapping out propane bottles! See how this discussion came back around!
One thing I might pass on to others that I had to learn on my "new" fridge after the Amish fixed me up, was the new thermostatic fan. I turn off the fridge after getting home and does not matter if it was on electric or propane, the fan keeps running? For a while!
I called them and they said that is normal. Anytime something new happens, both of my eyebrows go up. I am sure those of you who know fridge stuff know why it does it. I just needed to know it is not a bad thing....
Guessing that when the heating process that creates cooling, cools off enough, she shuts down?
All I need to know is that is not another thing I don't need to fix...
now, small dishes are passe. With Netflix, Roku, Brit Box, Disney, Hulu, etc, no need for a dish,IF you have internet., or strong wifi signal. We steamed a few Movies in evenings in Ak.
now, small dishes are passe. With Netflix, Roku, Brit Box, Disney, Hulu, etc, no need for a dish,IF you have internet., or strong wifi signal. We steamed a few Movies in evenings in Ak.
I agree Chessie, but we still like to see BBC news and a few other non streaming channels. And don't forget the bonus of endless episodes of my 400 pound life and Real Housewives of Los Angeles and the pimple popper!
We are about to dump it. Also finally got her parents to quit trying to reach us on the home phone. Got rid of that. $15 dollars here, $22 there. It all adds up.
We don't turn on the TV in the bus but we are not full timing. I play guitar, look at the bus a lot, and Rita uses WiFi for her Real Estate business as needed, but then shuts it OFF. Reads a book.
Any bus trip is an escape from electron bombardment. I don't even keep up with BCM or BGM when on the road, but our trips are only a week or two long at the most.
Just purchased a $199 4.5 cu. ft. fridge/freezer from HD. It's a Magic Chef and of coarse made in China. Draws 1.3A when running. It's for our Camp Malemute tiny home in AK. We like the absorption frige/freezer in the bus. Most of our conversion is 12VDC & LP. The diesel heaters we added aren't as popular when we added them as The difference between LP @ 3.50/gal.vs. diesel @ 5.50/gal. Oh & LP stayed @ 3.50/gal. through the whole fuel roller coaster. Go figure!
Quote from: dtcerrato on August 28, 2022, 11:52:48 AM
Just purchased a $199 4.5 cu. ft. fridge/freezer from HD. It's a Magic Chef and of coarse made in China. Draws 1.3A when running. It's for our Camp Malemute tiny home in AK. We like the absorption frige/freezer in the bus. Most of our conversion is 12VDC & LP. The diesel heaters we added aren't as popular when we added them as The difference between LP @ 3.50/gal.vs. diesel @ 5.50/gal. Oh & LP stayed @ 3.50/gal. through the whole fuel roller coaster. Go figure!
Took the coach out for a run and filled it with fuel it's been a while since I bought fuel damn $559.92 for 121 gals of fuel
Quote from: luvrbus on August 30, 2022, 01:55:53 PM
Took the coach out for a run and filled it with fuel it's been a while since I bought fuel damn $559.92 for 121 gals of fuel
We're getting close to pulling the plug on Alaska. I hate the thought of the return fuel expense. Outside of the great summer temps up here this trip involved very little "vacationing". We completed the mission of having something comfortable enough here if we decide to fly rather than drive the bus. Damned fuel cost has the priorities of earlier times all flip flopped.
The bus sat right where it's at since we pulled in. Did a couple camp out overnights with the toad to curb the expenditures. Figuring hugging in on 4 grand to get to home base - fuel only... Wifey flew back home over a month ago so it's a long solo trip home. Gonna leave the toad up here so hoping for some better fuel economy. We're gonna take in the Nappanee IN rally on the return home to FL. Hope it's issue free. No wife no dog - what's a man to do?
we are in Ohio KOA tonight. Home to Pa. tomorrow. Looks like diesel back up. A lot of $5.38 every where. Don't remember such a consistent price. Probably Labor Day price jack.
It will be interesting how that new all electric J4500 will pan out. I would imagine since it's built on the same J4500 platform, they could repower it with diesel if they don't like it. Same with these over the road trucks but time will tell with those too.
Diesel engines burn so clean and are so efficient now they will be around for a long time ,it will take years to upgrade our electric grid to handle the EV's.I see the line daily of EV's in line waiting for a charge in Needles,the owner of the local DQ say he loves the EV's his business is booming from people waiting for a charge.With the lost revenue from fuel taxes every highway in America will become a friggn toll road
Shorter runs<200 miles with this EV J4500 may be fine but long distance charters not so much. I don't have the greatest confidence that the people at the hotel would even know how to work the charger and keep it in good repair. For my experience, if the hotel can't even vacuum the hallways and make sure there's coffee for breakfast, what makes you think some 20 year old can make sure the EV chargers are gonna work?
Yes, diesel is going to be around for awhile yet.
Quote from: luvrbus on August 31, 2022, 04:31:45 AM
Diesel engines burn so clean and are so efficient now they will be around for a long time ,it will take years to upgrade our electric grid to handle the EV's.I see the line daily of EV's in line waiting for a charge in Needles,the owner of the local DQ say he loves the EV's his business is booming from people waiting for a charge.With the lost revenue from fuel taxes every highway in America will become a friggn toll road
Don't have to have toll roads like they used to. All the new cars have GPS tracking built in, the state will just bill you for the miles traveled each month.
Quote from: Lee Bradley on August 31, 2022, 04:11:57 PM
Don't have to have toll roads like they used to. All the new cars have GPS tracking built in, the state will just bill you for the miles traveled each month.
That is one way to do it, anyways the green deal is going to cost and you could make bet government agencies are not giving up the tax dollars generated from fuel sales
Quote from: luvrbus on August 31, 2022, 04:49:31 PM
That is one way to do it, anyways the green deal is going to cost and you could make bet government agencies are not giving up the tax dollars generated from fuel sales
Here in WA state you pay an $100.00 for your car tabs for electric vehicles. Of course that covers the state not the federal government.
there will only be savings till widespread adoption. after that, all kinds of fees will be added. then comes summer brownouts. and regularily running major storms with power disruptions, and what about hurricane mandatory evacuations, etc?
Is vehicle batttery theft going to follow catalitic converter theft?
early adopters will reap biggest savings for first few years. how many years is unknown.
every battery I've ever seen or experienced has a reduction of state of charge capacity as time passes. Although my norelco shaver cordless has lasted for years and still holds a decent charge length. I've also heard Priuus's are going beyond 8 years on battery life.
Battery charge seems to vary. I too have a NORELCO shaver I use every day. It's 7 years old and it lasts up to 2 weeks on a charge. Yet my weed eater has killer power for about 15 minutes then needs over 6 hours to charge it. Those batteries in that new J4500 EV will over time lose capability and I shudder to think if it will suddenly crap out in extreme hot or cold weather ruining a charter trip.
The state of CA asks people not to use their EV's over the labor day weekend,because of other problems their grid is overloaded, and we were asked to reduce our power usage so the power can go to CA ,could be the 1-amp draw fridges would help CA too :^
after they blamed the power company for all the fires, Me thinks the power company is going to not be in the best of mood in the future. more power! no coal, no oil, no natural gas, no nuclear! Use wind power and solar. yeah, right.
A fun game to play with people who are lefties. Name a method how to generate electricity and they'll likely find an excuse why it shouldn't be utilized.