Compressor Fridge for Overlanding: Power, Size, Zones

In short: For overland travel, a compressor cooler’s power consumption is the most important factor, followed by voltage (12 or 24 V), then size and zones. Allow about 1 A on average at 12 V, or around 24 Ah per day, and choose the cooler based on the number of days you’ll be stationary. We stock ARB, Engel, and National Luna in our shop.

As of November 2, 2026. Prices are the shop prices on that day. Technical specifications are based on manufacturer data and our product data; sources are listed at the end.

Why choose a compressor cooler instead of a thermoelectric cooler?

A compressor cooler works like a home refrigerator: a compressor compresses refrigerant, allowing the cooler to maintain its temperature regardless of the outside temperature and freeze contents if desired. ARB states that the Zero series offers a temperature range of +10°C to −22°C, while Engel states +10°C to −18°C for the MT series. Thermoelectric coolers (Peltier) can only cool to a fixed temperature below the ambient temperature and draw power continuously. At 35°C in a car, the contents will remain lukewarm. For Morocco, Scandinavia in summer, or a week without an electrical outlet, a compressor cooler is the only option.

Location also matters: according to our product data, the Sawafuji compressor in Engel coolers also works at an incline of up to 30°. On rough tracks and steep slopes, that’s the difference between a cold beer and a cooler that shuts down.

How much power does a compressor cooler really need?

Calculate based on the average power consumption over 24 hours. The power rating on the nameplate only applies while the compressor is running, and it doesn’t run continuously; it cycles. How often it cycles depends on the outside temperature, the set temperature, the contents, and how often you open the lid.

Two manufacturers’ specifications help put this into perspective. ARB tested its 15 Ah battery pack with a Zero 44 L cooler: at an ambient temperature of 25°C and a cooler temperature of 4°C, it ran for up to 18 hours according to ARB. This averages about 0.8 A at 12 V. Engel states a variable current of 0.5 to 3.0 A for the 40-liter cooler, meaning the maximum is around 36 W. Our product data lists a power consumption of 32 W for Engel coolers and 40 to 75 W for National Luna.

Use this calculation for your trip, with assumptions in parentheses:

Step	Calculation	Example (44-liter cooler, 12 V, warm summer day)
1. Average current	Operating current × operating time ratio	4.65 A × 25% operating time (assumption) ≈ 1.2 A
2. Daily requirement	average current × 24 h	1.2 A × 24 h ≈ 28 Ah per day
3. Usable battery	Capacity × usable portion	100-Ah AGM × 50% = 50 Ah; 100-Ah LiFePO4 × 80% = 80 Ah (assumptions)
4. Stationary time without driving	usable Ah ÷ daily requirement	AGM: just under 2 days; LiFePO4: just under 3 days

The 4.65 A is the current draw ARB states for the Zero 44 L at 20°C. The 25% operating time ratio is an assumption for a warm day with a pre-cooled cooler. At 35°C in the trunk, in freezing mode, or with warm drinks in the compartment, it will increase significantly. If you’re stationary for more than two nights, you’ll need a second battery with a battery booster or solar power. How a second battery and battery booster work together is explained in the overland build-out guide; you can find components under Power & Solar.

12 V, 24 V, or 230 V: Which connection is right for your vehicle?

Cars, pickups, and SUVs have 12 V onboard electrical systems, while trucks and many expedition vehicles use 24 V. All coolers in our shop run on 12 V, and according to the manufacturer, the ARB Zero and Engel MT series also run on 24 V; our product data shows that National Luna coolers also run on 12/24 V. The ARB Zero also has an input for 100 to 240 V AC on the front, with mains power taking priority. Engel MT series coolers have a built-in 230 V power supply, while it is optional with National Luna.

Battery protection is important. According to the service manual, the ARB Zero on 12 V shuts off in “Low” mode at 10.1 V and restarts at 11.1 V, and in “High” mode at 11.8 V, restarting again at 12.6 V. If the cooler is connected to the starter battery, use the high setting, otherwise the engine may not start in the morning. If it is connected to a LiFePO4 second battery whose voltage remains flat until the end, the low setting makes sense. A thin cable to the cigarette lighter socket causes voltage drop, so a permanently installed cable with its own fuse is worth it. ARB offers a 12/24 V mounting socket for €18.99.

One or two zones: What are the benefits of a two-zone cooler?

A single-zone cooler is either a refrigerator or a freezer. A two-zone cooler has two separately controlled compartments, so you can keep fresh food at 4°C and frozen goods at −18°C at the same time. According to ARB, the ARB Zero 69 L DZ is divided into 24 and 45 liters, with a removable divider; remove it to use it as a single-zone cooler. The Zero 96 L has two compartments, each with its own lid. National Luna builds its “Twin” models with a separate freezer lid, such as the NL50 with 38.3 liters for cooling and 11 liters for freezing.

The second zone takes up space, adds weight, and uses a little extra power. ARB states that the 69-liter cooler consumes 2.9 kWh compared to 0.8 kWh for the 60-liter single-zone cooler, without specifying the time period for either. For two weeks in Scandinavia with fish in the freezer, it is worth it; for weekend trips with cheese and drinks, one zone is enough.

Which size is right for your trip?

The volume in liters says little without knowing the shape. Flat, long coolers like the National Luna drawer coolers fit under a cargo area cover with a hardtop, while tall coolers need clearance above when the lid is open. Therefore, measure the length, width, and height with the lid open before purchasing. The NL50 is 50.6 cm high when closed and 84.5 cm with the lid open.

Volume	Typical use	Examples in the shop (external dimensions according to product data)
14 to 21 L	Second cooler, drinks, medication	Engel MD14F (442 × 395 × 284 mm, 11.5 kg), Engel MD27F (549 × 465 × 307 mm, 17 kg)
32 to 45 L	Two people, weekend to one week	Engel MT35 32 L (647 × 408 × 364 mm, 22 kg), ARB Zero 44 L (675 × 423 × 496 mm, 23.9 kg), Engel MT45 40 L
50 to 60 L	Two to four people, longer trips; ARB recommends the 60-liter cooler for a family of 4 to 5 people over a long weekend	ARB Zero 60 L (755 × 470 × 500 mm, 24.6 kg), ARB Elements 60 L, National Luna NL52
69 to 128 L	Two zones, expedition, group	ARB Zero 69 L DZ (755 × 469 × 564 mm, 28.3 kg), ARB Zero 96 L DZ (935 × 548 × 509 mm, 32.9 kg), National Luna NL125

The weight of the cooler plus its contents plus a drawer can quickly reach 60 kg. This counts against the vehicle’s load capacity and should be stored low and as centrally as possible.

ARB, Engel, or National Luna: Which brand is right for you?

As of November 2, 2026, we stock three brands with active compressor coolers: ARB with 5 models, Engel with 6, and National Luna with 17. We do not stock Dometic coolers. There is no single test winner; the table shows what the manufacturers state.

	ARB Zero / Elements	Engel MD / MT	National Luna Legacy Smart QC
Housing	Powder-coated steel; Elements made of stainless steel, weather-resistant for open cargo areas	MD: ABS plastic; MT: painted steel	Stainless steel
Voltage	12/24 V DC, 100–240 V AC built-in (Zero)	MT: 12/24/230 V built-in; MD14F 12 V only	12/24 V, 230 V power supply optional
Compressor	Variable-speed compressor, boost function	Sawafuji Swing Motor, variable current of 0.5 to 3.0 A, operates at an incline of up to 30°	Manufacturer specification not available to us; power consumption according to product data: 40–75 W
Temperature	+10°C to −22°C	+10°C to −18°C	Down to −24°C (60 L drawer cooler), −30°C (NL125) according to product data
App	Bluetooth, ARB app	No information in our data	NL Connect, Bluetooth
Two zones	Zero 69 L and 96 L	No	Twin models NL35, NL45, NL50, NL60, NL70, NL72, NL90, NL110, 40/60 L drawer coolers
Manufacturer warranty	3 years	5 years	No information in our data
Shop price	From €1,006.49	From €751.99	From €981.99

You can find all coolers and accessories under Coolers, the brands under ARB, Engel, and National Luna. The ARB Elements 60 L is built for open cargo areas and trailers and is dust-, water-, and UV-resistant, according to ARB.

How to safely install the cooler in your vehicle?

A loose 25 kg cooler becomes a projectile in a sudden stop. Secure it using tie-down points or a tie-down bracket; ARB offers a tie-down kit for the Zero for €48.49. A drawer pulls the cooler out from the back of the trunk, allowing you to access the contents without climbing over the cargo edge. The ARB drawer for the Zero 36 and 44 L costs €571.99, while the Front Runner cargo drawer costs €375.00 for coolers from 40 to 52 liters.

Give the compressor some breathing room. Heat must be dissipated, otherwise the cooler will cycle more often and draw more power. An insulating transit bag, which costs €193.49 for the Zero 44 L at ARB and €93.49 for the MT35 at Engel, reduces consumption in the sun and protects the housing. And pre-cool the cooler on 230 V before departure, so it draws hardly any power from the battery during the trip.

Frequently Asked Questions

Is my starter battery sufficient for a compressor cooler?

Usually yes for one night, if the battery protection is set to the high setting. According to the service manual, the ARB Zero then shuts off at 11.8 V. For several days without driving, you need a second battery with a battery booster or solar power. Allow around 24 to 30 Ah per day at 12 V.

Should I run the cooler on 12 V or 24 V?

Use the voltage of your onboard electrical system. Cars, pickups, and SUVs use 12 V, while trucks and many expedition vehicles use 24 V. According to manufacturer and product data, the ARB Zero, Engel MT, and National Luna run on both voltages, while the Engel MD14F runs on 12 V only.

What are the benefits of a two-zone cooler?

Two separately controlled compartments, so you can cool and freeze at the same time. The ARB Zero 69 L DZ has 24 and 45 liters according to ARB, with a removable divider. One zone is enough for weekend trips, while the second is worth it for long trips with frozen goods.

What size do I need for two people?

For two people and up to one week, 32 to 45 liters is common, such as the Engel MT35 or MT45 and ARB Zero 44 L. ARB recommends the 60-liter cooler for a family of 4 to 5 people over a long weekend. Measure the height with the lid open beforehand.

How much power does a compressor cooler draw per day?

As a rule of thumb, about 1 A on average at 12 V, or around 24 Ah per day. ARB operated the Zero 44 L at 25°C with a 15 Ah battery for up to 18 hours, which averages 0.8 A. In heat, in freezing mode, and with frequent opening, it will be more.

How are coolers delivered?

As a parcel; the delivery time is stated on each product page. Shipping is free for orders of €599 or more, and you have a 14-day right of withdrawal.

Sources

• ARB: Zero Fridge Freezer 44 L, technical specifications (current draw 4.65 A at 20 °C, 0.8 kWh, variable-speed compressor)
• ARB: Zero Fridge Freezer 69 L Dual Zone (24 + 45 L, 2.9 kWh)
• ARB: Zero Service Manual (12/24 V DC, 100–240 V AC, battery protection thresholds)
• ARB: Accessories for Zero coolers, Power Pack 15 Ah runtime with 44 L cooler
• Engel Australia: 40-litre cooler MT45F (12/24/240 V, Sawafuji Swing Motor, 0.5 to 3.0 A, 5-year warranty)

If you have any questions about power supply and installation, you can reach us at +49 5101 8159430 or hello@trail-setter.com.