We get asked this question a lot. If you have a generator, sure you can run your airconditioner.
But if you're like us and prefer not to have the constant hum in the background, then the answer is...
Most caravan van airconditioners use 1400-1700w. Starting from a hot van, it will draw 115A - 155A from your batteries and will run pretty much flat out for the first hour before the temp is low enough and it then starts to cycle on and off.
After this, it will drop to around 50-70A per hour.
But this all depends on the outside temperature.
To run for 6 hours you can expect to use as much as 450ah. Which means you need between 1500 and 1700w of solar to keep up with this in good solar conditions charging LiFePO4 batteries, or more again for AGM (being that lithium batteries are more efficient when charging compared to lead acid batteries). You would also need substantial battery storage.
Keep in mind this is only for running the Aircon, so you need more solar and batteries again for the rest of your loads. Fridge, kettle, microwave, toaster, coffee machine, laptops, TV, lights, pumps, fans etc.
As you can see, for most this is simply not feasible for long durations.
However, if you only want to run for say 2 hours a day, just to cool things down before going to sleep, then expect to use 150-200ah and 650-860w of solar to recharge it next day.
If you're like me and can't get to sleep when it is hot, running the aircon on a timer as you fall asleep can ensure you still wake up with the ability to make coffee.
We here at Offroad Living are obviously in a fairly unique situation.
We have the very large flat roof space on the truck with 900w of solar (room for another 150w if required) and 480w on the van. Room for more, but will see how we go.
You'll also need an inverter to convert the 12V power to 240V.
Our AllSpark 2000w inverter will run any caravan air conditioner on the market as long as your batteries can power it and solar can keep up. Not all 2000W inverters can guarantee this, so best to check with the manufacturer before hand.
On top of the batteries, the solar and the inverters, then there is the DCDC chargers. These keep your batteries topped up whilst driving.
You will need one for the van and one for your vehicle at least. We opted for the RedArc Manager 30, paralleled with a RedArc 1250D, running through the RedArc Redvision TVMS for our truck (450W running through each).
In the van we run an Enerdrive ENCDC40+ for charging whilst driving (another 600w can connect here later if required). A Victron Smartsolar controls the 480W of solar on the roof.
While it may seem cost prohibitive for most, running an airconditioner off grid can be achievable, it just depends on how long you want to run for, how hot it is inside and outside and how much roof space you have.
If you're like us, travelling full time (especially with kids) park fees to make it through hot days (or even cold, for heating) can add up quickly. Take where we are atm, coming into 5 days above 40C, we have seen a mass exoudous to caravan parks, as people seek power to plug into.
As always, every situation and set up is unique. If you need a hand working out your set up drop us a line, Jas will work out a solution to suit your needs.