Campervan Fridge Power Consumption: Compressor vs Absorption

The fridge is almost always the single biggest power consumer in a campervan — it runs 24 hours a day, every day. Choosing between a compressor and an absorption fridge is not just about cooling performance; it directly determines how large your battery bank, solar array and charging system need to be. This guide gives you real-world wattage figures, daily amp-hour consumption for both technologies, and the battery sizing maths so you can pick the right fridge for your setup.

1. How each fridge type works

Understanding the cooling mechanism explains why their power profiles are so different.

Compressor fridges work exactly like your kitchen fridge. An electric compressor circulates refrigerant through an evaporator. The compressor cycles on and off — when the interior reaches the target temperature it shuts down, and it restarts when the temperature rises above the threshold. This cycling (the “duty cycle”) is what makes compressor fridges efficient on 12V: the compressor typically runs only 30–50% of the time.

Absorption fridges (also called 3-way fridges) use a heat source — either a gas flame, a 12V heating element, or a 230V mains element — to drive a chemical absorption cycle with ammonia and hydrogen. There is no compressor and no moving parts. On gas, this process is very efficient. On 12V, however, the heating element draws a constant 8–10 amps with no duty cycle, making it extremely battery-hungry.

2. Compressor fridge: real power draw

Compressor fridge manufacturers quote a rated wattage (the power the compressor draws when running), but the number that matters for battery sizing is the average 24-hour consumption in Ah, which depends on the duty cycle.

“Moderate” = 20–25°C ambient, fridge set to 4°C, opened 5–8 times/day. “Hot” = 30–38°C ambient, frequent opening. Real-world figures will vary, but these are representative of owner-reported measurements.

3. Absorption fridge: real power draw

Absorption fridges are designed as 3-way units: they can run on 12V DC, 230V AC, or LPG gas. Their power profile varies dramatically depending on which mode you use.

The key takeaway: never run an absorption fridge on 12V while parked. At 8–10 amps constant draw, it will drain a 100Ah battery in under a day. The 12V mode exists for driving (where the alternator covers the load), while the gas mode is for stationary off-grid use.

On gas, an absorption fridge typically consumes 100–200 grams of LPG per day — a standard 907 Camping Gaz cylinder (1.8 kg net) lasts roughly 10–14 days of fridge-only use. A full-size 6 kg or 13 kg bottle lasts much longer.

4. Side-by-side comparison table

5. Battery impact: how many Ah per day?

The fridge is your baseline load — it runs whether you are cooking, sleeping or hiking. Everything else (lights, phone charging, water pump) adds on top. Here is how a fridge fits into a typical daily consumption budget:

The fridge alone accounts for 50–70% of total daily consumption in most campervan builds. This is why getting the fridge choice right is the single most impactful decision for your battery and solar sizing.

Battery sizing formula

To size your battery around the fridge:

1. Start with your total daily Ah (e.g. 55 Ah)
2. Divide by your battery’s usable depth of discharge (80% for lithium, 50% for AGM)
3. Multiply by the number of off-grid days you want without recharging

Example: 55 Ah/day ÷ 0.8 (LiFePO4) × 2 days = 138 Ah minimum. A 200Ah lithium battery gives you comfortable headroom for two days off-grid without any solar input.

6. Solar sizing for your fridge

Since the fridge runs around the clock, solar panels need to generate enough during daylight hours to both power the fridge and replenish what it consumed overnight.

These figures assume 4–5 peak sun hours in Southern Europe (Spain, southern France, Italy) and 2.5–3.5 hours in Northern Europe (UK, Scandinavia, northern Germany). A DC-DC alternator charger provides a valuable backup on cloudy days. For a detailed solar sizing guide, see our article on how many solar panels you need.

7. Tips to reduce fridge power consumption

Regardless of which fridge type you choose, these habits can cut consumption by 20–40%:

• Pre-cool at home. Load the fridge with already-cold food and drinks. It takes far less energy to maintain 4°C than to cool down from room temperature.
• Minimise door openings. Every opening lets warm air in. Know what you want before you open the lid.
• Keep it full. A full fridge holds its temperature better than an empty one. Fill gaps with water bottles.
• Park in the shade. Direct sun on the fridge (or on the van body near the fridge) can increase duty cycle by 30–50%. A windshield sun reflector and ventilated cabinet space help too.
• Set the right temperature. 4°C is the food safety standard. Going to 2°C increases consumption by 10–15% with no real benefit for most foods.
• Insulate the cabinet. For built-in fridges, adding 20–30 mm of foam board around and behind the unit noticeably reduces heat gain.
• Ensure ventilation. Compressor fridges need airflow around the condenser coil at the back. A blocked vent makes the compressor run longer. Leave at least 50 mm clearance.

8. Which fridge type should you choose?

The answer depends on your vehicle type, power infrastructure and travel style:

Choose a compressor fridge if…

• You have (or plan to install) a lithium battery bank of 100Ah or more
• You have 200W+ of solar panels
• You travel in warm climates where cooling performance matters
• Your van does not have a built-in gas system
• You want the fridge to work while driving on rough roads (no levelling required)

Choose an absorption fridge if…

• Your motorhome already has a gas installation and a large gas locker
• You frequently use hook-ups (campsites with shore power)
• You value silence above all else (bedrooms near the fridge)
• You do not want to upgrade your battery bank or solar array