AC power

[gkidsdlite]

I am wondering if you can run the AC on your batteries with a inverter, or do you have to use the gen? Plan on mostly boondocking and don't know much about the power supplied by batteries! I will have solar to recharge batteries but don't know if that will work for AC! Thanks

 

[dieselguy]

In a word ... no. You'd have to have some setup to supply enough juice to run an A/C off batteries.

 

[gkidsdlite]

I knew it was prob a dumb question but now I know! Thanks Dieselguy!

 

[DQDick]

You also need to figure what your usage will be to get some idea of the size of inverter and the number of batteries you need. Our rigs have a lot of phantom power draws (monitors, control boards, dvd players and Tv's that are always on, etc.) then if you want to run a coffee pot or your microwave you need to make sure you have what it takes. It also helps to convert your lights to LED if you don't have a new rig that came that way. Not only do you save on the electric draw by the amount of heat generated is significantly less. As Dieselguy says, the only way to run AC is with a generator. 2 Honda's or Yamaha's = 1 AC to run 2AC's you'll need a much larger genny or a built in one.

 

[Art-n-Marge]

well, hold on now. If you increase the number of batteries you use, or convert to four 6v batteries and use a large enough inverter, say 3000 Watts you just might be able to run an A/C, but who knows for how long. Then you'd need quite a few solar panels to help keep the batteries charged.

It's about how much you want to spend and how long you will be able to keep things charged. I don't do this but know that a few friends have some very serious electrical supply systems to be "off-the-grid".

I would not read dieselguy's "no" as a "no way at all". He did qualify it that you would need some setup, and knowing how the batteries drain, how fast they drain with an A/C and what else would affect the drain and how to lessen the draw with a real good recharging system, it's not a resounding "no" but would probably be more expensive than buying and wiring a suitable generator. But not using a generator means you might save some weight (except with the better than average batteries that will be heavy) and not having to spend on fuel to run it. Then there's the noise factor, too.

The point being a solar system is lighter, quieter, does not need fuel but does require sunlight, so for extended storms a generator as a backup provides the best for all conditions if you are willing to spend on having all bases covered.

At my house I now have a Solar system and so far it is saving me a ton of electricity costs during the day. The only costs are because at night I am back on the grid so it will be a little while before I get the price of the system back (I do not have battery storage, yet). Same thing with an RV if you install the right stuff, except the batteries allow you to remain off the grid even at night.

 

[Ozz]

This ties into this tread, LED lights can really save you money.. and power.

Think Michael and Kat and their Filament free site

Here is a good link to check out I found:

https://picasaweb.google.com/Jimsue13/LEDMichaelAndKat?authuser=0&authkey=Gv1sRgCMe_uNTxtJCdvwE&feat=directlink

 

[RickW-MOC]

It can be done ...... but not cheaply. As already stated it will take a huge battery bank to run the AC. Then if you plan on using solar to try and recharge the batteries you will most likely need more roof space than you currently have. Plus when you have solar and are off the grid it is still recommend to have a generator for when there is not enough sun to recharge the batteries.

As for how much power the AC actually needs, I have a 3k Honda. It will power 1 AC. But at higher elevations (over 6k foot) it struggles. Recently at 6500' needed the AC to cool the trailer off. Had to shut all electrical loads down in order to get the compressor. That was running the generator at full throttle. It struggled when the AC cycled so we had to turn the temp down all the way to keep it from cycling until it just flat out froze us out then turn the AC off as the trailer slowly warmed back up.

 

[mhs4771]

A quick rule of thumb for Inverters on a 12 Volt system is 10:1, 10 amps of 12 volt power to make 1 amp of 120 volt AC. So to run and AC with approx 15 amp draw would require approx 150 amps of battery power. These numbers are by now means exact, but just give you a ball part figure of the battery power needed.

 

[Alwims-MOC]

As you can see from my signature, I have 596 watts of Solar panels running into 6 6volt golf cart batteries running into a 2000 watt inverter and the whole system is just barely enough to run the whole trailer except the air conditioners. At that, we don't run the fridge or hot water heater on solar either. They run on propane. Granted, we don't conserve very well as we are running a small chest freezer and we forget to unplug the Bunn Coffee Maker quite often. We also use the microwave to defrost meat and warm cold coffee. The key to our system is anything that can be LED is LED, including our 32" TV and 24" security camera monitor. IMHO, you don't have enough roof surface to install the amount of Solar panels it would take to run even a small window air conditioner for any amount of time. There just isn't room up there. Also as an added note, our 2000watt inverter generator won't start the compressor on either of our 2 air conditioners.

 

[gkidsdlite]

Sounds as if the solar thing is not going to work then if it is limited to lights and Tv and minor things that you would use ,(coffee pot etc) If you have to run the gen for AC then you would be able to charge your batteries at all times with it. Is my thinking correct?

 

[Alwims-MOC]

If you have a big enough generator. My battery charger draws 55 amps and some of the newer one draw a lot more. IMHO, a 3000 watt generator is going to be marginal if not large enough to do what you're wanting to do. Not intending to be so negative, just trying to save you a little headache if not a little money also.

 

[Ozz]

My Honda 2000 runs fine charging my 95 amp charger off of the Magnum Inverter, I can generally run some light loads as well. I have the generator on the rear carrier, so it is a short plug-in.

 

[Alwims-MOC]

quote:Originally posted by Ozz

My Honda 2000 runs fine charging my 95 amp charger off of the Magnum Inverter, I can generally run some light loads as well. I have the generator on the rear carrier, so it is a short plug-in.

I may have read gkidsdlite's post wrong and if I did, my apologies, but I understood he wanted to run his air conditioner and charger at the same time.

 

[Ozz]

You are fine, I think he was interested in running his A/C off of an Inverter. I was just saying your 2000 watt gen should run the converter/charger with no problems.

 

[gkidsdlite]

Trying not to confuse or be confused but, batteries or solar will not run AC, I got that. I will need a gen for AC! Does that gen have to go thru an inverter for alt current? The gen will not power AC and charger at the same time! I've got that. So it looks like a gen for AC and solar to recharge batteries. Can you hook the battery series into the truck so that it will charge the batteries while in transit?

 

[Ozz]

When traveling down the road, you can charge up the batteries with the generator, if you are set up to do that, the truck is more like a trickle charge, it would not give the 3 stage charge needed. You need to boil the electrolyte; or the Bulk charge, that's where the most charge is needed as the charger dictates. (If that makes any sense at all..)

 

[Alwims-MOC]

quote:Originally posted by gkidsdlite

Trying not to confuse or be confused but, batteries or solar will not run AC, I got that. I will need a gen for AC! Does that gen have to go thru an inverter for alt current? The gen will not power AC and charger at the same time! I've got that. So it looks like a gen for AC and solar to recharge batteries. Can you hook the battery series into the truck so that it will charge the batteries while in transit?

"The gen will not power AC and charger at the same time!" Not exactly what I said. Figure out how much wattage your air and your charger needs then use a generator with enough wattage to handle both and then some. We, before solar, have powered our whole 5th wheel and one air conditioner with a 5000 watt generator with no problems.

"Does that gen have to go thru an inverter for alt current?" No, generators put out an AC alt current of usually 110 and/or 220 volt. If it is not an inverter generator it will usually put out a modified sine wave that will power most anything in your trailer.

There are better explanations than what I've provided, but these are the basics.

 

[gkidsdlite]

Thanks everyone!!! I now feel like I know what I need to know. I'm sure I will be back with more questions at some other time.

 

[h2ojocky]

Consider buying 2 Honda 2000 watt generators. Cheaper than one 3000 watt Honda and it puts out more power and is quieter and conserves more fuel. Several people on this site use 2 Honda's.

 

[Art-n-Marge]

I do use 2 Honda 2000s and their 4000 watt max is a better output than a single 3000W especially when you realize that those are Peak wattages. Run time will typically be 3200W and 2700W and can be why an A/C might struggle with only 2700W and you are at higher altitudes and the wattage drops anyway. So say it drops to 3000W & 2400W. Hopefully you get the idea. The biggest drawback to the dual Honda 2000s is the smaller fuel tanks, but then you get to learn about providing an auxiliary gasoline supply to increase runtime.

Remember that when running the generators there is a converter being used to convert the 110v to 12v to power 12v devices. This converter uses 4-6 amps to do this and takes away from other 110v stuff. That's why there's a lot to gain by running the fridge and water heater off 12v (and propane) and converting bulbs to very low power LED types.

It's a balancing act to switch over things as you need to but being able to boondock provides many different opportunities than what can be achieved being connected to that big power cord to a shore power connection. Being able to power manage the conveniences in the RV brings the best options when visiting the less civilized but beautiful parts of our country. I use a power cord and will live within these limitations, but if I win the lottery, I'll invest in these other options, unless the grandkids have other plans for our winnings.