What Is The Best Generator To Run Dorm Fridge & AC?

[John61CT]

Sticks and brick, aka regular stationary life.

Aircon is not practical for most rigs off solar, just consumes too much energy.

 

[jimindenver]

Sticks and brick, aka regular stationary life.

Aircon is not practical for most rigs off solar, just consumes too much energy.

Brahahaha
John is so funny.

Ok how much solar would I need to run a window unit AC alone with no fridge. I can always opt for a 12 volt fridge.

I run my energy star rated 5000 BTU window shaker off of 750 watts of flat mounted panels on my trailer mid day in the summer. It takes my full 1185 watts in the winter due to the lower sun. It sounds like a lot but I have seen vans with 1000 watts up top. I am told Canadian Solar has a 425 watt panel, two would do it year round if they tilted.

When I say run it, I mean off the power produced by the panels alone with no loss in voltage at the battery. Running it day and night is more of a pain because now you have to have the battery capacity to run it over night AND twice as much solar to run it during the day and recharge those batteries to run it again that night.

In a 24/7 situation it may be better to use a generator to power the A/C during the day while charging the batteries for the night time use. That way no one has to hear the generator at night and you do not have to be a rolling power station worried that it is going to cloud up.

 

[John61CT]

Not saying impossible. Just impractical, for most.

A large vehicle, and large up front investment needed for all the gear required.

Not to mention consistently great insolation conditions, basically moving to the south west when he's trying to *avoid* hot conditions.

And even then, how many hours a day is practical without the genny.

Given my interpretation of these specific circumstances, IMO likely not feasible.

 

[jimindenver]

I ran it daily in Yuma and Ehrenberg last year from 9 AM to 5 PM or so. I could have started it earlier knowing the panels would have replaced the power through out the day.

 

[jonyjoe303]

Running air con off solar/batteries is possible but only if your van is large enough. Hurriedyear website shows you how he did it in his van, so it is possible. 

But with plenty of insulation and large enough swampcooler you wouldnt need a generator or large solar array. Even with an air conditioner, having your van heavily insulated would reduce its workload where you can run it on low all the time. Swampcooler won't introduce any humidity into your van, I've been using them for years. If its humid outside its going to be humid inside your van, if its dry outside its going to be dry inside your van even with the swampcooler running all day. Swampcooler is the only true alternative you have, fans and roof vents just move hot air from one area to another area.

I run my swampcooler off a 240 watt panel and a 110 ah battery, I can literally run it 24 hours a day if I wanted to on my system. A 110 ah battery might run an AC for an hour maybe. One thing about swampcoolers they work best at night, and also comsume less water. You can use the air conditioner during the day and at night you can run the less power hungry swampcooler off batteries.

 

[earthling]

Running air con off solar/batteries is possible but only if your van is large enough. Hurriedyear website shows you how he did it in his van, so it is possible. 

But with plenty of insulation and large enough swampcooler you wouldnt need a generator or large solar array. Even with an air conditioner, having your van heavily insulated would reduce its workload where you can run it on low all the time. Swampcooler won't introduce any humidity into your van, I've been using them for years. If its humid outside its going to be humid inside your van, if its dry outside its going to be dry inside your van even with the swampcooler running all day. Swampcooler is the only true alternative you have, fans and roof vents just move hot air from one area to another area.

I run my swampcooler off a 240 watt panel and a 110 ah battery, I can literally run it 24 hours a day if I wanted to on my system. A 110 ah battery might run an AC for an hour maybe. One thing about swampcoolers they work best at night, and also comsume less water. You can use the air conditioner during the day and at night you can run the less power hungry swampcooler off batteries.

I am in the planning stages of my van build out and have priced some sheep's wool insulation (now that insulation has been mentioned in this thread) and have heard people bring up that it's for cold weather but I'm thinking it should be great for hot climates as well if you have a good cooling & energy system that is...not that I want to hang out in AZ during the summer months (where I've lived for 40 years) BUT, I don't really want to venture too far out of AZ my first year.  Any thoughts on this?  Thanks for bringing up the swampcooler idea as well...something else I need to check into although when the humidity picks up, they are not much good.  What brand/size do you have and is it the portable kind or do you have it mounted to your vehicle somehow?

 

[HerzeleidMeister]

Sticks and brick, aka regular stationary life.

Ah ok, thanks. I'm new to this so the abbreviations may trip me up sometimes.

Its starting to look like Alaska would be wonderful in the summer and ditching the AC idea LOL. It has to be super cold in the summer inside for me or else I end up with heat exhaustion. I've had it happen this past summer because the AC was not cranked high enough. We typically keep it around 65-68 degrees.

 

[Weight]

There are roof mounted RV air conditioners. You would need more than 2000i watt generator for that. Swamp cooler will not get near <70 F unless starting at 75 F. They will do nothing to reduce humidity.

 

[NoMadYesHappy]

I'm no expert, but I did some online snooping and some quick math.

I'm going to make statements, but in the end, they really are questions. In short, it seems like 2000W portable generator would power a 5000 btu window AC. I didn't look at the portable AC units, but energy is energy.

According to the manufacturer, a 5000 btu window AC uses about 1600 watts during startup, and about 350 continuous watts once running: https://www.walmart.com/ip/Haier-5-...er-115V-White-Factory-Reconditioned/711845071

Watt requirements in 115V should = the same watts in 12V (1st law of thermodynamics).

A Ryobi 2000W portable generator will produce 2300 watts max, and 1800 watts continuous. This one is marketed as "super quiet" and has an inverter with 2 X 120V receptacles, bluetooth (to monitor gas?) and USB ports: https://www.homedepot.com/p/Ryobi-B...gital-Inverter-Generator-RYI2300BTA/300347426

At 115V, the unit pulls 13.3A to start, 3.0A continuous.

My math says that at 12V = 128A to start, 29A continuous.

It seems like you COULD start the AC using a generator, and then run it for about 6 hours off of 400Ah of battery, assuming no recharge from panels, longer if you have lots of solar and good sun.

Granted, there are efficiency losses that I didn't account for, but it seems like you could make it work?

But, y'all have been doing this for a while, and say it can't be done for the most part. I must not know something? Where did I go wrong?

 

[rayrey]

Most roof mount RV A/C's require a 3000 series inverter generator except at high altitude where they stop having the guts to start them at around 8000 ft. There is a new 9000 BTU 12v roof A/C that pulls just 600 watts but it's nearly $2000. There have been people that claim their 2000 series inverter generator will run their regular roof mount A/C but even if it does it is running balls to the wall doing it.

Swamp coolers do work in the right environment but it takes a much larger swamp cooler than it does a A/C and they require something that is not easy to find in the dry desert where they do best....water. They do introduce humidity via the evaporation process that creates the cooling effect. Without the proper amount of ventilation everything in the space being cooled becomes muggy and it will not be long before you see sweat not just on yourself but on everything.

With small A/C or swamp coolers you will get more of a cooling breeze on you effect than a cooling of the whole area.

 

[jimindenver]

Most roof mount RV A/C's require a 3000 series inverter generator except at high altitude where they stop having the guts to start them at around 8000 ft. There is a new 9000 BTU 12v roof A/C that pulls just 600 watts but it's nearly $2000. There have been people that claim their 2000 series inverter generator will run their regular roof mount A/C but even if it does it is running balls to the wall doing it.

Swamp coolers do work in the right environment but it takes a much larger swamp cooler than it does a A/C and they require something that is not easy to find in the dry desert where they do best....water. They do introduce humidity via the evaporation process that creates the cooling effect. Without the proper amount of ventilation everything in the space being cooled becomes muggy and it will not be long before you see sweat not just on yourself but on everything.

With small A/C or swamp coolers you will get more of a cooling breeze on you effect than a cooling of the whole area.

 

[jimindenver]

I'm no expert, but I did some online snooping and some quick math.

I'm going to make statements, but in the end, they really are questions.  In short, it seems like 2000W portable generator would power a 5000 btu window AC.  I didn't look at the portable AC units, but energy is energy.

According to the manufacturer, a 5000 btu window AC uses about 1600 watts during startup, and about 350 continuous watts once running:  https://www.walmart.com/ip/Haier-5-...er-115V-White-Factory-Reconditioned/711845071

Watt requirements in 115V should = the same watts in 12V (1st law of thermodynamics).

A Ryobi 2000W portable generator will produce 2300 watts max, and 1800 watts continuous.  This one is marketed as "super quiet" and has an inverter with 2 X 120V receptacles, bluetooth (to monitor gas?) and USB ports: https://www.homedepot.com/p/Ryobi-B...gital-Inverter-Generator-RYI2300BTA/300347426

At 115V, the unit pulls 13.3A to start, 3.0A continuous.

My math says that at 12V = 128A to start, 29A continuous.

It seems like you COULD start the AC using a generator, and then run it for about 6 hours off of 400Ah of battery, assuming no recharge from panels, longer if you have lots of solar and good sun.

Granted, there are efficiency losses that I didn't account for, but it seems like you could make it work?

But, y'all have been doing this for a while, and say it can't be done for the most part.  I must not know something?  Where did I go wrong?

350 watt is better than the 5000 BTU unit I have rated for 410 watt, I thought I had found the lowest rated unit. My old one was rated for 446 watts and that is what the kill a watt showed once the head pressure was up.  So yes a 2000 series inverter generator running at 1600 watts should run one with ease. My 800 watt invertor generator runs mine at seal level but may require some creativity at high altitudes.

 

[Spaceman Spiff]

 . . . It has to be super cold in the summer inside for me or else I end up with heat exhaustion. I've had it happen this past summer because the AC was not cranked high enough. We typically keep it around 65-68 degrees.

IMO you need to talk to a mobile HVAC professional.  It sounds like AC is a medical necessity not a comfort issue.  If that is the case you need to be able to run AC 24 hrs a day; and you need a plan B.

Swamp coolers are not reliable enough as a medical device and do not reduce humidity.

If you plan on running a generator be aware that you will have very angry neighbors if you run it a lot or overnight.  And the sound can carry far in some conditions.  It is possible to quiet them down so they aren't heard, but the stuff to do that is large and cumbersome.

Moving somewhere that is cool is probably the best solution but you still need to have a plan for abnormally hot/humid weather.  Others with experience can speak to the humidity/bug issues in Alaska.

 

[breeze]

Without being bound to a geographical area, a 2nd (large 280a Nation's) alternator and Home Depot large Grape solar panels charging along with Li-Ion seems to be the only known feasible solution for van size ac at current available technology.

Big RV's use 5k btu window units underneath their side panel lower skirts, which is perfect for a bus size rv: but you better get a Bus drivers license too. Good luck with that. For a van size rv, with room in your van, roof ac's seem like a feasible solution. LOW ac's is the name of the game for a high roof van anyway. It's a game of vertical inches above your roof. Dometic Penguin II (13.5k btu) is a fraction of an inch below 10" above roof, but it takes up 40" x 30" space on your roof: which leaves barely enough room for 2 ~200 w (Home Depot) Graoe solars on the roof too, for extra help beyond 280 a alternator. For a couple of more inches Dometic has another possibly better roof ac, but just the thought of screeching your ac is bad enough! (Just TINY branches SKREETCH on your roof!) And Coleman is a garbage product, so don't consider their 8" high ac.

At 2" below 10' high for my NV High Roof, I constantly hit branches on the street and parking lots: trying to park in the shade or even in a parking space alone. With a parking ac, I won't have to worry about that though. Split units, portable ac's, swamp coolers for dry West USA, and truck driver ac's (or dehumidifiers) all have compelling arguments, but for real ac's on a high roof van (esp. in SE USA), Dometic Penguin II seems to have the market place roof top ac argument now. And if you opt for the West USA Swamp coolers, then your playground just got a lot smaller for outdoor mountains (SE USA) and major metropolitans (East USA.) Ymmv.

 

[Weight]

I have seen many vans and short buses with window type AC units create-fully installed. But don't fool yourself that it is possible to use solar and batteries to power them. You will need a generator. To recharge the battery bank or to run the AC. A big roof full of solar is a different problem. It is not that generators are loud, it is the steady monotonous drone that gets us pissed-off.

 

[HerzeleidMeister]

IMO you need to talk to a mobile HVAC professional.  It sounds like AC is a medical necessity not a comfort issue.  If that is the case you need to be able to run AC 24 hrs a day; and you need a plan B.

Moving somewhere that is cool is probably the best solution but you still need to have a plan for abnormally hot/humid weather.  Others with experience can speak to the humidity/bug issues in Alaska.

Yes its a medical necessity for both myself and my sister. We talked about it last night and I think what we are going to do is stay up north in the summer and make sure that we install a fantastic fan and have other small fans & vents within our rig to keep circulation going.

As for Alaska we both have wanted to go there for quite some time anyways lol. And I have some work arounds for the bugs in mind that should work just fine. Avon Skin So Soft is great stuff for keeping the little blood suckers away! And Alaska has a plethora of those tiny menaces.

 

[John61CT]

Without being bound to a geographical area, a 2nd (large 280a Nation's) alternator and Home Depot large Grape solar panels charging along with Li-Ion seems to be the only known feasible solution for van size ac at current available technology.

Alternators only work while driving, silly to run the propulsion engine for long periods when stationary.

A van doesn't have roof space for enough solar, like 30' OK but still limited hours, weather etc issues.

Brand of solar of course is irrelevant

Only a generator or mains work for this case IMO.

 

[jimindenver]

Everything has limitations.

Shore power is wonderful until that extension cord reaches it's ends. (no free boondocking for you )

generators are too until the gas runs out or run times are restricted officially or otherwise.

Solar and battery in this case is big, expensive, limited by conditions and still needs a generator to back it up.

Ideally you need a RV, even a class B that has a built in generator and A/C. Following the weather can work most of the time but then you are limited to where you go by the prevailing temperatures. Generally though it is pretty easy to at least not need A/C at night doing so.

As for those that say you can not and have never tried, look to those that have for they never got the memo and are doing it.

 

[duncanshannon]

I run my energy star rated 5000 BTU window shaker off of 750 watts of flat mounted panels on my trailer mid day in the summer. It takes my full 1185 watts in the winter due to the lower sun. It sounds like a lot but I have seen vans with 1000 watts up top. I am told Canadian Solar has a 425 watt panel, two would do it year round if they tilted.

Hi Jim - have you / can you detail your system more?? Sounds like something lots of people would love to see and try!

 

[breeze]

Everything has limitations.

Shore power is wonderful until that extension cord reaches it's ends. (no free boondocking for you )

generators are too until the gas runs out or run times are restricted officially or otherwise.

Solar and battery in this case is big, expensive, limited by conditions and still needs a generator to back it up.

Ideally you need a RV, even a class B that has a built in generator and A/C. Following the weather can work most of the time but then you are limited to where you go by the prevailing temperatures. Generally though it is pretty easy to at least not need A/C at night doing so.

As for those that say you can not and have never tried, look to those that have for they never got the memo and are doing it.

Jim, you are a leader for sure and everyone here appreciates you. But some technologies used can be improved upon for a higher price tag. That price is not unreal now when costing all expenses and benefits appropriately.

https://www.thefitrv.com/rv-tips/how-much-solar-do-i-need-on-my-rv/

The fit rv is "doers" of a New type rv electrical system. Except you don't need a $150K rv like they started with. It can be done with a 2012 to 2016 Nissan NV high roof (or anything really.)

The problems it overcomes are:
1. Solar charging capacity and time (alone by itself, esp. for running an ac),
2. No work-you-to-death generator gas runs, and loud smelly diesel chargers (no generator at all!),
3. Don't generally need shore power,
4. No break your back 500 lbs. of lead acid batteries sloshing around with their high levels of expert maintenance and low levels of reliability.

The dual engineer on Fit RV is my guide and he "has" done and broadcasts what he does weekly or so. I cheat and save time by starting out with what he has done first (on electrical systems and cheap fixes), and then add on innovations since his posts (He is a dual engineer and a REAL rocket scientist or engineer rather.) He is a genius like Bob who I also follow faithfully and both are hard to dispute anything they say, although Fit RV guy is sponsored by some vendors: but all suggestions are safe bets for the most part, if that is your immediate goal and you have the money. For example, I found out about Sumo rear shock springs (for $209 in his followers feedback when he was trying out a multiple thousand dollar electronic leveling system.) Sumo rear shock springs are Fantastic and I never see the need any thing else suspension wise except worn out parts.

Even if you have the answers in front of you, as you well know, it's still not easy absorbing all the interrelated technologies. But I think it's easier than what you learned with lead acid batteries being a 'black art' of unknown and expertise factors. On the other hand, not many people know anything about Li-ion and 2nd alternator 'system' (no-maintenance) charging, so you have to depend on a few (real busy) vendors. Ymmv.