RV/Van Life Refrigerator Power Calculator
Created by: Ethan Brooks
Last updated:
Calculate daily power consumption of your RV or van refrigerator. This calculator estimates amp-hours, watt-hours, battery requirements, and solar panel capacity needed to run your 12V compressor or absorption fridge off-grid.
What is an RV/Van Life Refrigerator Power Calculator?
A Refrigerator Power Calculator helps RV and van owners estimate daily power consumption of their 12V or absorption refrigerator. This tool calculates watt-hours, amp-hours, and recommends battery and solar capacity needed to run your fridge off-grid.
Whether you're sizing a new electrical system or understanding your current power budget, this calculator accounts for ambient temperature, usage patterns, and fridge efficiency to provide accurate power estimates.
Understanding Refrigerator Power Consumption
Daily Amp-Hours: Running watts ÷ voltage × duty cycle × 24 hours
Duty Cycle: Percentage of time compressor runs (30-70% typical)
Peak vs Average: Startup surge is 3-5x running watts for compressor fridges
Temperature Impact: Hot weather increases duty cycle significantly
Frequently Asked Questions
How much power does an RV refrigerator use?
12V compressor fridges typically use 30-60 watts while running, averaging 1-3 amp-hours per hour depending on size and conditions. Daily usage ranges from 30-60 Ah for most RV fridges. 3-way absorption fridges on electric use 150-200 watts continuously.
What's the difference between compressor and absorption RV fridges?
Compressor fridges (like Dometic CFX, Isotherm) use an electric compressor, are efficient, and work in any orientation. Absorption fridges (Norcold, Dometic RM) can run on propane, 12V, or 120V AC but are less efficient on electric and must be level.
How do I calculate fridge duty cycle?
Duty cycle is the percentage of time the compressor runs. In moderate conditions (70°F ambient), expect 30-40% duty cycle. In hot weather (90°F+), duty cycle increases to 50-70%. Monitor actual run time to calculate: (run time ÷ total time) × 100.
Should I run my RV fridge on propane or electric?
If boondocking with solar, compressor fridges on 12V are most efficient. Absorption fridges are cheapest on propane (about $0.25-0.50/day) but require venting and level parking. Shore power makes any fridge economical on AC electric.
How much solar do I need to run an RV fridge?
For a typical 12V compressor fridge using 40-50 Ah/day, plan for 100-150W of solar panels with good sun exposure. Account for cloudy days and other loads by sizing up. Absorption fridges on DC are less efficient and need more solar.
Why does my fridge use more power in summer?
Higher ambient temperatures force the compressor to run more frequently (higher duty cycle) to maintain interior temperature. A fridge in 90°F conditions might use 50-100% more power than at 70°F. Improve ventilation and shade to reduce power consumption.
Can I run an RV fridge while driving?
Yes, 12V compressor fridges run directly from your vehicle's electrical system while driving. Absorption fridges should run on 12V (not propane) while driving for safety. Your alternator easily handles fridge power while the engine runs.
How long will my battery run an RV fridge?
A 100Ah lithium battery (usable capacity) will run a typical 12V compressor fridge for 2-3 days. Lead-acid batteries provide only 50% usable capacity, so a 100Ah lead-acid gives 1-1.5 days. Always factor in other electrical loads.
Sources and References
- Dometic Corporation - 12V Compressor Refrigerator Specifications
- Isotherm - Marine and RV Refrigeration Technical Data
- Norcold - RV Absorption Refrigerator Owner's Manual
- Battle Born Batteries - RV Refrigerator Power Consumption Guide