Campervan power station: which size for a UK weekend?

For a weekend in a campervan without a hook-up, a station of about 700 to 1,000 Wh is enough. Without a cool box you will come home with charge to spare. With a 12 V compressor cool box running day and night, you need about 1,000 Wh plus a little sun, or a hook-up on one of the nights.

What a campervan weekend actually uses

Here we count two days and two nights: Friday evening to Sunday afternoon. Here is a typical day, with our site averages and a cool box figure based on the maker’s data:

Device	Watts	Hours a day	Wh a day
Compressor cool box (12 V socket)	15 W average	24 h	360 Wh
LED lamp (USB or 12 V)	8 W	5 h	40 Wh
Two phones (USB)	10 W each	3 h	60 Wh
Laptop (230 V socket)	60 W + 10 W for the station	2 h	140 Wh
Total with cool box			600 Wh
Total without cool box			240 Wh

The maths: 15 × 24 = 360, 8 × 5 = 40, 10 × 3 × 2 = 60, (60 + 10) × 2 = 140. Add them and you get 600 Wh.

Why the cool box is the big one

A compressor cool box only runs its motor some of the time. Dometic gives 0.98 Ah per hour at 12 V for its CFX3 35, measured with 32 °C outside. That is about 12 W on average (0.98 × 12). We use 15 W to leave a margin for a warm van and frequent opening.

It runs all day and night, so it uses more than everything else put together. Over the 12 V socket the station does not need its 230 V sockets switched on, so we leave out the extra 10 W for that line.

How long three stations last

Our runtime rule is battery Wh × 0.85, the share you can really use once losses are taken off. Then divide by what you use per day.

Station (battery announced by the brand)	Usable Wh	Days with cool box (600 Wh)	Days without (240 Wh)
EcoFlow RIVER 2 Pro (768 Wh)	≈ 653 Wh	≈ 1.1 days	≈ 2.7 days
Anker SOLIX C1000 (1,056 Wh)	≈ 898 Wh	≈ 1.5 days	≈ 3.7 days
Jackery Explorer 1000 v2 (1,070 Wh)	≈ 910 Wh	≈ 1.5 days	≈ 3.8 days

Example: 1,056 × 0.85 = 897.6 Wh, and 897.6 ÷ 600 ≈ 1.5 days.

So without a cool box, any of the three gets you through the weekend from a full charge. With the cool box, even the 1 kWh models run out on Sunday morning unless you top up. To try your own list, use the runtime calculator.

What a roof panel adds in a British summer

A solar panel never gives its full watt rating for long. The European Commission’s PVGIS tool estimates what a panel actually produces, place by place and month by month. For a panel lying flat, like one on a van roof, it gives these daily figures per kW of panels, after typical system losses:

Place	June	July	October
Birmingham	3.98 kWh	3.87 kWh	1.32 kWh
Fort William	3.29 kWh	3.04 kWh	0.80 kWh

A 100 W panel is a tenth of a kW. So in Birmingham in July it gives about 3.87 × 100 = 387 Wh a day on average, and about 130 Wh in October. In the west Highlands, count on less.

These are averages over many years. A grey, wet weekend can give a fraction of this, and parking under trees cuts it further.

Does that close the gap?

With the cool box, a weekend needs about 1,200 Wh. A full Anker SOLIX C1000 gives about 898 Wh. Two July days with a 100 W panel add roughly 700 to 800 Wh, so you finish with charge left over. In October the same panel adds only about 260 Wh over two days, which is not enough on its own.

Check the solar input each brand announces: 220 W for the RIVER 2 Pro, 400 W for the Jackery Explorer 1000 v2 and 600 W for the Anker SOLIX C1000. A 100 W or 200 W panel fits all three.

Practical points for the van

Weight and space

The brands announce 7.8 kg for the RIVER 2 Pro, 10.8 kg for the Jackery Explorer 1000 v2 and 12.9 kg for the Anker SOLIX C1000. In a small van, the lighter box is easier to move from the cab to the table to the tent.

Strap it down

A 10 kg box that slides under braking is dangerous. Wedge it in a cupboard or use a strap fixed to a proper anchor point.

Charging while driving

The 12 V socket in the cab charges slowly, and the speed depends on the station and the vehicle. It helps, but do not count on it to refill a big station on a short drive. Anything wired into the van’s own electrics, like a split charge system or a fixed battery, is a job for a qualified professional.

To compare two of these models side by side, see RIVER 2 Pro vs Jackery Explorer 1000 v2, or open the EcoFlow RIVER 2 Pro page.

In short

• Without a cool box, a campervan weekend takes about 240 Wh a day, and a 768 Wh station is plenty.
• A compressor cool box adds about 360 Wh a day and doubles what you need.
• In a British July, a 100 W flat panel gives roughly 300 to 400 Wh a day on average; in October, about a third of that.
• Strap the station down and leave fixed wiring to a professional.