Should you buy a power station or dual battery system to run a fridge, lights and devices at camp? A portable power station is a battery, inverter and outlets in one box that you can carry. A dual battery system, by contrast, is a second battery that an installer fits in the vehicle and the alternator charges. Both can run a weekend camp. However, they differ in how they charge, what they cost to set up and how flexible they are.
Power station or dual battery at a glance
| Portable power station | Dual battery system | |
|---|---|---|
| Installation | None, or a simple charging cable | Battery, DC-DC charger, wiring and fuses in the vehicle |
| Charging while driving | Limited from a 12V socket, better if hardwired | Built in, through a DC-DC charger |
| Solar | Usually built-in solar input | Through a DC-DC charger or separate regulator |
| 240V/110V power | Built-in inverter | Needs a separate inverter |
| Use away from the vehicle or at home | Yes | No |
| Moves between vehicles | Yes | No |
| Space | Takes up cargo or cabin space | Can go under the bonnet, in a drawer or a canopy |
The big difference: charging while you drive
Most overlanders recharge mainly by driving. A dual battery system with a DC-DC charger does exactly that. It can put a steady charge into the battery every time the engine runs. Our DC-DC charger guide explains how to size one.
In contrast, a power station plugged into a 12V accessory socket charges much more slowly. That’s because manufacturers usually fuse these sockets at around 10–15 amps, and many power stations limit car charging to roughly 100–120W. That’s fine for topping up on a long drive but slow for refilling a large unit. Some power stations can be charged through a hardwired DC-DC charger, which closes most of the gap.
How much capacity do you need?
Manufacturers rate power stations in watt-hours (Wh) and vehicle batteries in amp-hours (Ah). To compare them, multiply the amp-hours by the battery voltage, about 12.8V for lithium:
- 100Ah lithium ≈ 1,280Wh
- 1,000Wh power station ≈ 78Ah at 12.8V
- A 50-litre fridge using about 36Ah a day ≈ 460Wh a day
For example, a 1,000Wh power station could run that fridge for about two days with nothing else connected, before losses. Also, running the fridge from the 12V outlet rather than through the inverter avoids extra losses. Use our 12V power calculator to work out your own daily use.
When a power station makes more sense
- You do weekend trips and short holidays.
- You change vehicles, rent vehicles or travel with a family member’s car.
- You want backup power at home during outages too.
- You can’t or don’t want to modify the vehicle, for example on a leased car.
- Your loads are moderate: a fridge, lights, phones, a laptop.
When a dual battery makes more sense
- You drive most days and want reliable charging from the alternator.
- You’re doing longer or remote trips where power has to just work.
- You run heavier 12V loads, or want everything wired permanently into drawers and a canopy.
- You want to free up cargo space.
Keep in mind that the cost of a dual battery system isn’t only the battery. Budget for a DC-DC charger, cabling, fuses, a mount and installation. Our 12V power guide goes through each part, and the lithium vs AGM guide helps you pick the battery.
The middle ground
Choosing a power station or dual battery is no longer either-or, because the line between the two is blurring. For instance, you can now charge some power stations through a proper DC-DC charger. Ready-made units such as the systems in our REDARC REDWorks explainer combine battery, charging and outlets in one box that is still fitted to the vehicle. For many people, a power station plus a hardwired charging cable is a sensible first step, and a full dual battery system can come later as part of an overland build.
Quick answers
Can a power station run a 12V fridge?
Yes. Use the 12V outlet rather than the AC outlet to avoid inverter losses, and check that the unit’s capacity covers your fridge’s daily use with some margin.
Is a dual battery system worth it for weekend trips?
Often not. After all, a power station is cheaper to start with, needs no installation and can be used at home. A dual battery system pays off when you travel often or for longer.
Can I charge a power station while driving?
Yes, from the 12V socket, but slowly. For faster, more reliable charging, use a hardwired DC-DC charger that’s compatible with your power station.
Sources
- Unsealed 4X4 – Is a dual battery system still necessary?
- Outback Equipment – Solar panels compared (fridge consumption figure)
Figures in this article are estimates for comparison. Check your power station’s charging limits and your vehicle’s socket ratings, and ask a qualified auto electrician to install any permanent wiring.
Featured photo: Leo_Visions on Unsplash.
