Fridge power planning
Estimate whether your solar and battery setup can keep an RV refrigerator running, then separate fridge-only survival from the full daily load of the rig.
Quick fridge read
The entered solar harvest covers the 745Wh/day fridge estimate, but the whole rig still runs a daily deficit of about 295Wh after other loads.
Fridge demand
Battery-side daily draw after duty-cycle and heat adjustments
Whole-rig runtime
2.5 days if the fridge were the only load
Solar coverage
1.4 kWh estimated harvest per day
Fridge math is only as good as the appliance data. Use measured watt-hours when possible, check ventilation and installation guidance, and keep a backup cooling or charging plan for food-safe trips.
Start over
This calculator stores inputs locally in this browser. Clear saved inputs when stale values are getting in the way.
Fridge solar calculator
Enter the fridge type, wattage, duty cycle, battery reserve, and solar harvest. The result separates fridge-only survival from the whole-rig daily load so the answer does not get falsely optimistic.
Fridge power verdict
The entered solar harvest covers the 745Wh/day fridge estimate, but the whole rig still runs a daily deficit of about 295Wh after other loads.
Fridge demand
745 Wh
0 Wh inverter loss included
Whole-rig demand
1.6 kWh
900 Wh from other entered loads
Battery runtime
1.1 days
2.5 days if the fridge were the only load
Solar coverage
82%
1.4 kWh estimated harvest per day
Sizing targets
Recommended solar
600W
3 x 200W panels, rounded up from a 500W math floor
Battery for autonomy
400Ah
3.3 kWh needed for 2 days
Daily surplus / deficit
-295 Wh
295 Wh deficit after solar
Usable battery
1.8 kWh
15% reserve after lithium usable-depth assumption
Watch-outs
Fridge power changes with outdoor temperature, ventilation, sun on the fridge wall, food loading, door openings, thermostat setting, and freezer use.
Nameplate watts are not daily watt-hours. The duty cycle and ambient adjustment are what turn a rated load into a planning number.
If you have a plug-in watt meter or battery monitor history, use measured daily watt-hours instead of generic duty-cycle assumptions.
Recommended next move
Reduce other daily loads, add solar, or plan alternator/generator recovery before calling the whole off-grid day covered.
Why this exists
Fridge solar math gets misleading when it stops at the appliance. This calculator shows the fridge draw, then adds the rest of the daily rig load so you can see whether the solar array is actually keeping up or just slowing down the battery draw.
Use this with
Solar calculator
Use this after the fridge estimate to size the whole solar system around all daily loads.
Run the RV solar calculatorBattery calculator
Use this when the fridge result says battery reserve is the limiting factor.
Run the battery bank calculatorRecharge time calculator
Use this when solar does not recover the daily fridge and house-load deficit.
Compare recharge timeSolar to run an RV fridge guide
Use this for the practical tradeoffs between compressor, absorption, and residential fridge setups.
Read the RV fridge solar guideTool notes
This output helps you compare refrigerator demand, battery reserve, and solar recovery. It does not replace appliance labels, measured watt-hour data, battery monitor history, ventilation checks, or manufacturer installation guidance.
Rated watts are multiplied by hours per day and duty cycle, then adjusted for heat, ventilation, and usage conditions.
Residential AC fridges are adjusted for inverter efficiency so the battery-side draw is not understated.
Entered panel watts are multiplied by sun hours and derate, then compared against fridge-only and whole-rig daily demand.
Avoid these traps
A fridge compressor cycles. The useful planning number is watt-hours per day, not the wattage on the label by itself.
Solar may cover the fridge and still fail the day once lights, fans, laptops, Starlink, water pump, and parasitic loads are included.
A propane absorption fridge may use modest 12V control power, while electric heating mode can be a large continuous AC load.
Treat the calculator result as a planning range, then verify the relevant manufacturer guidance, safety limits, installation requirements, and local rules before changing the rig.See assumptions
Gear to compare after the math
These handoffs match the calculator family, not a one-click prescription. Verify fit, specs, clearances, and install limits before buying.
Rich Solar MEGA 200 Solar Panel
Best for
Expanding a roof-first array in 200W-class increments
Use this kind of panel when roof layout, controller limits, and wiring runs support adding more fixed wattage.
Current listing
Rich Solar MEGA 200 Solar Panel at Rich Solar.
Renogy 400W 12V Solar Premium Kit
Best for
A 400W starter kit when the calculator result is modest
Use this as a 400W kit, not a silent substitute for a larger array. For a 600W answer, treat it as the base kit plus another 200W panel and a fresh controller check.
Current listing
Renogy 400W 12V Solar Premium Kit at Renogy.
Victron SmartSolar MPPT 100/30
Best for
Controller planning for smaller RV solar arrays
A controller-class handoff for calculator results where panel wiring and current limits need a real hardware check.
Current listing
Victron SmartSolar MPPT 100/30 at Victron.
Frequently asked
Use measured data if you have it. If not, a compressor fridge often lands somewhere around 30-60% depending on heat, ventilation, thermostat, and door openings, while propane absorption control-board loads may run close to 100% at a much lower wattage.
It includes inverter conversion loss for residential AC fridge mode, but not every inverter's idle draw. If your inverter stays on all day just for the fridge, add its idle consumption to other daily loads.
Solar does not run the fridge at night; the battery does. Solar has to replace the prior night and day draw during usable sun hours, which is why the calculator shows both battery runtime and daily solar coverage.
Use fridge-only math to understand the critical load, then size the system around the whole rig. A cold fridge does not help much if the battery is also supporting internet, fans, lights, controls, and charging loads.