How many watts does a refrigerator use per day?
A refrigerator that draws 200 W while the compressor runs, running about a third of the day, uses about 1,600 Wh (1.6 kWh) a day — 1,778 Wh from a battery through a 90% inverter.
How to work it out
- AC loads: 1,600 Wh ÷ 90% inverter efficiency = 1,778 Wh
- + DC loads 0 Wh = 1,778 Wh a day
- 1,778 Wh ÷ 12 V = 148 Ah a day from the battery
Champion’s generator chart puts a household refrigerator at 150–400 running watts. The extension-service rule is that a fridge runs at full power about one hour in three, so the calculation uses 8 running hours a day — not 24.
Adjust for your project
More options: Inverter eff. · Idle W · Inverter on
- Per day in kWh
- 1.78 kWh
- Amp-hours per day at your system voltage
- 148 Ah · 12 V
- AC loads (before inverter losses)
- 1,600 Wh
- DC loads
- 0 Wh
- AC watts if everything runs at once
- 200 W
- Per month (30 days)
- 53.3 kWh
Appliance by appliance
| Appliance | Watts × hours | Per day | From battery |
|---|---|---|---|
| Fridge | 200 W × 8 h (AC) | 1,600 Wh | 1,778 Wh |
- Your inverter must carry at least 200 W continuous if all the AC loads can run at once, plus any motor starting surge — check it with the inverter size calculator.
The same loads at other inverter efficiencies
| Inverter efficiency | Energy per day (from the battery) | Amp-hours per day at your system voltage | Per month (30 days) |
|---|---|---|---|
| 80% | 2,000 Wh | 167 Ah | 60 kWh |
| 85% | 1,882 Wh | 157 Ah | 56.5 kWh |
| 90% | 1,778 Wh | 148 Ah | 53.3 kWh |
| 95% | 1,684 Wh | 140 Ah | 50.5 kWh |
What to know about a fridge’s daily energy
- Read the yellow label first. A US fridge’s EnergyGuide label lists estimated kWh per year. Divide by 365 for a daily figure — a 500 kWh/year fridge is about 1,370 Wh a day — and use that instead of the duty-cycle guess.
- Running watts ≠ nameplate watts. The extension list shows a 16 cu ft frost-free fridge at 725 W on its nameplate; that includes the defrost heater, which runs briefly. Using 725 W for 8 hours would roughly triple the estimate.
- Summer and door openings raise it. A hot kitchen or garage stretches the compressor’s run time well past one in three.
- Starting watts are separate. The compressor’s start surge (800–1,200 W on Champion’s chart) sizes the inverter, not the battery.
From here, how many solar panels to run a refrigerator sizes the panels, and what size inverter for a refrigerator covers the start surge. A 12 V compressor fridge is a different animal — see how long a 100Ah battery runs a fridge.
Different size? Use the full Solar Load Calculator.
What you’ll need
- Plug-in electricity usage monitorBudget price
Plugs in between the wall and a 120 V appliance and shows real watts and kWh over a day — the honest way to fill in a load list, especially for fridges that cycle on and off.
See options on Amazon (opens in a new tab) - Pure sine wave inverter, 1000 WMid-range price
Enough for a CPAP, laptop, TV and small appliances. Pure sine is the safe choice for anything with a motor or sensitive electronics.
See options on Amazon (opens in a new tab) - 12 V 100 Ah LiFePO4 batteryPremium price
About 1.28 kWh rated in a box roughly the size of a group 24–31 lead-acid battery at around half the weight. Check the BMS discharge limit and whether it can charge below freezing.
See options on Amazon (opens in a new tab)
As an Amazon Associate we earn from qualifying purchases. Links to products are affiliate links — they cost you nothing extra and help keep these calculators free.
Frequently asked questions
How many watts does a refrigerator use per day at 150 W running?
About 1,200 Wh at the plug — 1,333 Wh from a battery through a 90% inverter.
How much does a fridge and a chest freezer use per day together?
With the freezer at 100 W running a third of the time, about 2,667 Wh a day from the battery (2.67 kWh).
Other common sizes
- How much power Starlink uses per day — 1.8–2.4 kWh a day (about 2,667 Wh from a battery via an inverter)
- How much power the Starlink Mini uses — 600–960 Wh a day on 12 V DC
Sources
- Virginia Cooperative Extension, BSE-301: Estimating Appliance and Home Electronic Energy Use (2020) (opens in a new tab) — Wattage × hours ÷ 1,000 = kWh per day; watts = amps × volts when only amps are listed; a refrigerator runs at full wattage about a third of the time; typical nameplate wattages.
- Champion Power Equipment — Generator Wattage Chart (opens in a new tab) — Typical running and starting watts for household, RV and job-site appliances (a manufacturer’s planning chart — your nameplate wins).
- Victron Energy — Energy Unlimited (book) (opens in a new tab) — Lead-acid charge efficiency 80–95% (85% suggested as a starting value); battery energy efficiency about 75% for full cycles, about 89% in partial state of charge; inverter efficiencies above 90%.
- ENERGY STAR — Certified Televisions data set (on-mode power) (opens in a new tab) — Certified models, on-mode watts, retrieved October 2026: 32 in about 27–36 W; 43 in about 45–78 W; 50 in about 61–90 W; 55 in about 64–114 W; 65 in about 85–135 W; 75 in about 120–176 W.
- Starlink — Standard kit specification sheet (opens in a new tab) — Power consumption: average 75–100 W.
- Starlink — Mini specification sheet (opens in a new tab) — Power consumption: average 25–40 W; input rating 12–48 V, 60 W.