What size power station do you need for a van or RV?

Big enough to cover a day of what you run, times the number of days you might go without charging. That’s the whole method. If you run a 12V fridge, start with it, because it’s the one load that runs all day and all night.

Start with the fridge

A 12V compressor fridge doesn’t run constantly. It cycles on and off, so what matters is how much energy it uses over a whole day. Here’s a mid-size Dometic, the Dometic CFX3 45, on four stations from small to large. Dometic’s daily figure is in the note under the table.

Divide the hours by 24 and you have days. A small station like the EcoFlow RIVER 3 Plus doesn’t get the fridge through one full day on its own, so it only makes sense if you’re charging it every day. The EcoFlow DELTA 2 gets you about three days. The Bluetti Elite 200 V2 gets about six, and the EcoFlow DELTA Pro more than ten.

That’s on Dometic’s hot-day test figure. Cooler weather and a fridge you don’t open much will use less. A van parked in the sun all afternoon will use more. And a dual-zone fridge with one side set to freeze can use around twice what it does with both sides as fridge. Look at the dual-zone rows in Dometic CFX3 75DZ vs CFX3 95DZ before you size for one.

Add everything else

Then add the rest of your day. For each thing you run, you want watts and hours of use:

• CPAP: the machine’s draw times the hours you sleep. A ResMed AirSense 11 on its own runs 16.5 hours on the DELTA 2 over 12V, so on a station that size it takes a real bite out of the fridge’s days. More on that in our CPAP runtime table.
• Lights, fans, phones, a laptop: the watts are on the label or the charger. We don’t have these in our data yet, so you’ll need to look them up.
• Anything with a heating element: coffee makers, kettles, hair dryers, induction plates. These draw a lot while they’re on, even if it’s only for a few minutes.

Add it all up for one day, and that’s the number to compare against the station’s capacity. Our runtime calculator does one appliance on one station at a time. For a mix of loads you’ll have to add them by hand for now.

Run 12V things from the 12V port

Every 12V DC row in the table above beats its AC row, because the 12V port skips the inverter. The fridge and a CPAP with its DC adapter can both run that way. That gets you more out of the same battery.

There’s a limit, though. Every station in our data has the same car port rating, from the RIVER 3 Plus up to the DELTA Pro at 10 A. A bigger station doesn’t get you a bigger 12V port. Dometic rates the Dometic CFX3 95DZ above that, so our check still says yes, but only from the AC outlets. The Why column shows the 12V port failing:

How many days without charging?

If you drive most days and the station charges while you drive, you might only need one day of battery. If you park for a long weekend somewhere shady, you need all of it.

Solar changes the math, but only up to the station’s solar input limit:

• EcoFlow RIVER 3 Plus: 220 W
• EcoFlow DELTA 2: 500 W
• Bluetti Elite 200 V2: 1,000 W
• EcoFlow DELTA Pro: 1,600 W

A panel on the roof only helps as much as the input accepts, and a panel’s rating is what it makes in ideal conditions, not on a cloudy afternoon. The solar recharge calculator takes your panel wattage and local sun hours and tells you how long a refill takes. If it says longer than a day, solar slows the drain rather than stopping it, and you need more battery for the cloudy stretches.

We don’t carry vehicle charging rates in our data. Check your station’s manual for how fast it charges from a car outlet or an alternator charger.

Check the outputs too

Battery size isn’t the only limit. If you want to run a microwave, an induction plate or a hair dryer, its wattage has to be under the station’s continuous AC rating, and anything with a motor needs headroom for the startup kick.

Two stations here need care on that second part. EcoFlow’s manual for the RIVER 3 Plus and Bluetti’s for the Elite 200 V2 don’t give a surge rating, so our tables use the continuous rating as the limit. That’s a cautious stand-in, not a published figure. If you plan to start something big, like a rooftop air conditioner, ask the maker first. We don’t have RV air conditioner data yet, so we can’t size for one here.

Where to start

For a weekend with a 12V fridge, phones and lights, and charging most days: a station around the size of the DELTA 2. For a CPAP and a fridge, or longer stops without much sun: something like the Elite 200 V2. A dual-zone fridge with the freezer on is the exception. It uses enough that the Elite only gets you a couple of days, so look at the DELTA Pro rows before you settle. The DELTA Pro is for a week or more on a single-zone fridge without charging, or for running big AC appliances.

If you’re stuck between two of these, we compare the DELTA Pro and Elite 200 V2 for vans side by side.