Fridge power planning
RV fridge solar calculator
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.
Fridge solar calculator
Find out whether solar keeps the fridge cold or just slows the drawdown.
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
Solar can cover the fridge, but not the whole rig
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
500W
About 3 x 200W panels on these assumptions
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
A refrigerator is a critical load, but it is not the only load.
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.
Open next stepBattery calculator
Use this when the fridge result says battery reserve is the weak point.
Open next stepRecharge time calculator
Use this when solar does not recover the daily fridge and house-load deficit.
Open next stepSolar to run an RV fridge guide
Use this for the practical tradeoffs between compressor, absorption, and residential fridge setups.
Open next stepTool notes
What the fridge solar estimate is actually saying
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.
Fridge watt-hours
Rated watts are multiplied by hours per day and duty cycle, then adjusted for heat, ventilation, and usage conditions.
Battery-side demand
Residential AC fridges are adjusted for inverter efficiency so the battery-side draw is not understated.
Solar coverage
Entered panel watts are multiplied by sun hours and derate, then compared against fridge-only and whole-rig daily demand.
Avoid these traps
Common mistakes before buying
Using rated watts as daily consumption
A fridge compressor cycles. The useful planning number is watt-hours per day, not the wattage on the label by itself.
Forgetting the rest of the rig
Solar may cover the fridge and still fail the day once lights, fans, laptops, Starlink, water pump, and parasitic loads are included.
Treating absorption electric mode like propane mode
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 wiring, clearances, fusing, ventilation, and manufacturer limits before installation.See assumptions
Frequently asked
Questions RVers usually ask next.
What duty cycle should I use for an RV fridge?
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.
Does this include inverter idle draw?
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.
Can solar run an RV fridge overnight?
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.
Should I size solar for fridge-only or the whole rig?
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.