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RV Refrigerator Calculator — Propane vs 12V vs 120V Cost

Compare propane BTU, 12V amp draw, and 120V watt usage to find the cheapest way to run your RV fridge

Cheapest Power Source

12V DC

Propane

$0.81/day

12V DC

$0.09/day

120V AC

$0.29/day

$/gal
$/kWh
hrs

Cheapest Power Source

12V DC

Based on your energy prices

Daily Cost Comparison

Propane
$0.81/day
12V DC
$0.09/day
120V AC
$0.29/day

Propane

BTU/hr: 2,200
Gal/day: 0.23

12V DC

Watts: 60
Amps: 5.0
Ah/day: 48

120V AC

Watts: 200
kWh/day: 1.9

Frequently Asked Questions

Q

How much propane does an RV refrigerator use per day?

A typical absorption RV fridge (5–8 cu ft) uses about 1,200–1,500 BTU/hr, consuming roughly 0.3–0.4 gallons of propane per day. Larger units (12+ cu ft) can use 0.5–0.7 gallons per day. Hot ambient temperatures increase consumption by 30–60%.

  • Small 3–4 cu ft fridge: ~1,500 BTU/hr, ~0.16 gal/day at 40% duty cycle
  • Medium 5–8 cu ft fridge: ~2,200 BTU/hr, ~0.23 gal/day at 40% duty cycle
  • Large 9–12 cu ft fridge: ~3,000 BTU/hr, ~0.31 gal/day at 40% duty cycle
  • XL 13–18 cu ft fridge: ~4,000 BTU/hr, ~0.42 gal/day at 40% duty cycle
  • At $3.50/gal propane, daily cost ranges from $0.56 to $1.47 depending on size
SizeBTU/hrGal/DayCost/Day @$3.50
Small (3–4 cu ft)1,5000.16$0.56
Medium (5–8 cu ft)2,2000.23$0.81
Large (9–12 cu ft)3,0000.31$1.09
XL (13–18 cu ft)4,0000.42$1.47
Q

How many amps does a 12V RV fridge draw?

A 12V compressor fridge draws 3–8 amps depending on size. At 40% duty cycle, a medium fridge uses about 48–60 amp-hours per day. This is the key number for sizing your battery bank—plan for at least 200 Ah of lithium capacity.

  • Small compressor fridge: ~3.75 amps (45W), ~36 Ah/day
  • Medium compressor fridge: ~5.0 amps (60W), ~48 Ah/day
  • Large compressor fridge: ~6.7 amps (80W), ~64 Ah/day
  • 12V fridges are most efficient for off-grid boondocking with solar
  • Lithium batteries should not be drained below 20%, so size accordingly
Q

Should I run my RV fridge on propane or electric?

It depends on your energy costs and camping style. Propane costs $0.50–$1.50/day and works off-grid but requires leveling for absorption fridges. Shore power (120V) costs $0.15–$0.45/day and is cheapest at campgrounds. 12V is best for boondocking with solar.

  • Shore power (120V): cheapest at $0.12–$0.15/kWh, but requires hookups
  • Propane: works anywhere, costs ~$0.80/day for medium fridge at $3.50/gal
  • 12V DC: best for solar setups, requires adequate battery bank (200+ Ah)
  • Absorption fridges must be within 3° of level—compressor fridges work at any angle
  • In hot weather (90°F+), all power sources cost 30–60% more due to increased duty cycle
Power SourceBest ForDaily CostRequirement
PropaneOff-grid, absorption fridges$0.56–$1.47Level RV, propane tank
12V DCBoondocking with solar$0.07–$0.14200+ Ah battery bank
120V ACCampgrounds with hookups$0.14–$0.46Shore power connection
Q

What is the duty cycle of an RV refrigerator?

RV refrigerators typically operate at a 30–50% duty cycle, meaning the compressor or cooling unit runs 30–50% of the time and rests the remainder. A 40% duty cycle is the standard estimate. Higher ambient temperatures increase the duty cycle significantly.

  • Cool weather (60–70°F): ~30% duty cycle, fridge runs easily
  • Moderate weather (70–80°F): ~40% duty cycle, standard operation
  • Warm weather (80–90°F): ~50–60% duty cycle, increased energy use
  • Hot weather (90–110°F): ~60–70% duty cycle, add ventilation fans
  • Frequent door opening and warm food loading increase duty cycle further
Q

Can I run an RV fridge on solar panels?

Yes, but you need adequate solar and battery capacity. A medium 12V compressor fridge using ~48 Ah/day needs roughly 200–300W of solar panels and a 200+ Ah lithium battery bank. Absorption fridges cannot run directly on solar—they need propane or an inverter.

  • A 200W solar panel produces ~40–60 Ah/day depending on sun hours
  • Medium fridge needs ~48 Ah/day, so 200–300W solar is recommended
  • 200 Ah lithium battery gives ~160 Ah usable capacity (80% depth)
  • Add 30% buffer for cloudy days and other 12V loads
  • Compressor fridges (Dometic CFX, Iceco) are the only type suitable for solar-only setups

Example Calculations

1Medium Absorption Fridge on Propane

Inputs

Fridge TypeAbsorption (2/3-Way)
Fridge SizeMedium (5–8 cu ft)
Ambient TempModerate (70–80°F)
Propane Price$3.50/gal

Result

Propane Cost/Day$0.81
BTU/hr2,200
Gallons/Day0.23
Cheapest Source12V DC

2,200 BTU/hr × 24 hrs × 0.40 duty cycle = 21,120 BTU/day. Divided by 91,500 BTU/gal = 0.23 gal/day. At $3.50/gal = $0.81/day.

2Medium Compressor Fridge on 12V Solar

Inputs

Fridge TypeCompressor (12V)
Fridge SizeMedium (5–8 cu ft)
Ambient TempWarm (80–90°F)
Electricity Rate$0.15/kWh

Result

12V Cost/Day$0.11
Watts78W
Amps6.5A
Ah/Day62 Ah

60W base × 1.3 temp factor = 78W. 78W / 12V = 6.5A. 6.5A × 24h × 0.40 = 62.4 Ah/day. 78W × 24h × 0.40 / 1000 = 0.749 kWh. 0.749 × $0.15 = $0.11/day.

3Large Residential Fridge on Shore Power

Inputs

Fridge TypeResidential (120V)
Fridge SizeLarge (9–12 cu ft)
Ambient TempHot (90–110°F)
Electricity Rate$0.15/kWh

Result

120V Cost/Day$0.69
Watts480W
kWh/Day4.61
Monthly Cost$20.74

300W base × 1.6 hot factor = 480W. 480W × 24h × 0.40 / 1000 = 4.608 kWh/day. 4.608 × $0.15 = $0.69/day. Monthly: $0.69 × 30 = $20.74.

Formulas Used

Propane Consumption

Gallons/Day = (BTU/hr × Hours × Duty Cycle) / 91,500

Calculates daily propane consumption based on the fridge BTU rating, hours of operation, and duty cycle.

Where:

BTU/hr= Rated heat output of the refrigerator cooling unit
Hours= Hours the fridge runs per day (typically 24)
Duty Cycle= Fraction of time the cooling unit is active (~0.40)
91,500= BTU energy content per gallon of propane

12V Amp-Hour Consumption

Ah/Day = (Watts / 12V) × Hours × Duty Cycle

Calculates daily battery consumption in amp-hours for a 12V compressor fridge, essential for sizing battery banks and solar panels.

Where:

Watts= Rated power draw of the 12V compressor fridge
12V= Nominal DC voltage of the RV battery system
Hours= Hours of operation per day (typically 24)
Duty Cycle= Fraction of time the compressor runs (~0.40)

Daily Energy Cost

Cost/Day = (Watts × Hours × Duty Cycle / 1000) × Rate

Calculates the daily electricity cost for running the fridge on AC or DC power.

Where:

Watts= Power draw of the refrigerator in watts
Rate= Electricity cost in dollars per kWh
1000= Conversion factor from watt-hours to kilowatt-hours

RV Refrigerator Power: Propane vs Electric Comparison

Choosing the right power source for your RV refrigerator is one of the most important decisions for efficient RV living. The three main options—propane, 12V DC, and 120V AC—each have distinct cost profiles, efficiency characteristics, and practical requirements that make them suited to different camping styles.

Absorption refrigerators (2-way or 3-way) can run on all three power sources but require the RV to be nearly level. They use propane to heat an ammonia solution through a gravity-fed system. Compressor refrigerators run only on 12V DC (or 120V through an inverter) and work at any angle, making them ideal for van life and boondocking.

The daily operating cost varies dramatically based on your energy prices. At typical rates ($3.50/gal propane, $0.15/kWh electricity), a medium fridge costs about $0.81/day on propane, $0.09/day on 12V, and $0.14/day on 120V shore power. However, 12V requires a significant upfront investment in batteries and solar panels.

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Last Updated: Mar 25, 2026

This calculator is provided for informational and educational purposes only. Results are estimates and should not be considered professional financial, medical, legal, or other advice. Always consult a qualified professional before making important decisions. UseCalcPro is not responsible for any actions taken based on calculator results.

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