How many solar panels do you need to run a refrigerator?

By the SmartSolarSizer team · Published 20 October 2026

Start with the energy label, not the wattage

The one number that sizes solar for a fridge is printed on its energy label: kWh per year. That's the yellow EnergyGuide label in the US and Canada, or the kWh/annum figure on UK and EU labels. Divide it by 365 and you have the energy your panels have to replace each day.

A common mistake is to start from watts instead. Generator charts list a fridge at about 700 W running (Generac), and 700 W for 24 hours comes to 16.8 kWh a day. That's about 10 times what the 22.5 cu ft fridge in the table below really uses. A compressor cycles on and off, and the US Department of Energy suggests counting about a third of the hours a fridge is plugged in (DOE Energy Saver). Work backwards from that fridge's label with the same rule and it averages about 201 W while the compressor runs. Generator charts are written to size a generator, not to estimate how much energy an appliance uses in a day.

Here's what real ENERGY STAR certified fridges use:

Source: ENERGY STAR certified product listings. Older fridges, ice makers and fridges in hot garages use more.

Look at the first two rows. Certified 3.1 cu ft compacts use 195–320 kWh a year, and the one in our table uses 88% of what the 18 cu ft top-freezer does. Small doesn't automatically mean frugal, so check the label before you assume a mini fridge is the cheap option for an off-grid cabin.

How many solar panels to run a refrigerator, city by city

The sum is short:

Take that 22.5 cu ft bottom-freezer fridge in New York. It uses 1.61 kWh a day. One kW of panels there makes 3.85 kWh on an average day, so a 430 W panel makes 1.66 kWh, just over what the fridge needs. One panel. In December the same panel makes 1.21 kWh, which is why the darkest-month column in the city table below says 2.

The same bottom-freezer fridge in 14 places. The last column is the month with the least sun:

Which column should you use? On a grid-tied home, the average day: the grid fills the gaps. Off-grid, use the darkest month. A fridge that only stays cold in summer isn't much use.

Can a 100, 200, 300 or 400 watt solar panel run a fridge?

A single 400 W panel can run an efficient top-freezer fridge on an average day in all 14 places we checked. A 300 W panel manages it in 11 of the 14 places, a 200 W panel only in Phoenix and a 100 W panel in none of them. Here's what each size makes in a day, against the 0.99 kWh that fridge uses:

Average day across the year, from PVGIS. Winter output is lower everywhere outside the tropics.

Two catches apply to every row. "Covers it on an average day" means some days in the darker months fall short. And none of these panels runs the fridge at night on its own; the energy has to go through a battery first. A bigger fridge moves the line: the 1.61 kWh bottom-freezer model is beyond a single 400 W panel in 6 of the 14 places.

Mini fridges, 12 V fridges and camping fridges

Will a 100 watt solar panel run a mini fridge? Not the one in our table. It uses 0.88 kWh a day, and on an average day you'd need two 100 W panels in Phoenix, three in New York and four in London, plus a battery. Its compressor averages about 110 W while running (label energy and the DOE one-third rule), so a 500 W inverter is usually enough.

A 12 V or 24 V DC compressor fridge, the kind sold for RVs, boats, camping and off-grid cabins, changes the picture. It runs straight from the battery the panel charges, so there's no inverter and no inverter loss. If the spec sheet gives daily use in amp-hours, multiply by 12 (or 24) and divide by 1,000 to get kWh. Then compare that with the table above. The honest test is your worst month, not the average: a 100 W panel makes 0.28 kWh a day in a New York December and 0.12 kWh in a London December.

Even a 12 V fridge doesn't run directly from a solar panel. Panel output swings with every cloud and stops at sunset, so a charge controller and battery always sit in between.

What size inverter does a fridge need?

A household fridge runs on AC, so an off-grid or backup system needs an inverter, and the hard part is the start. The compressor motor pulls several times its running power for a moment each time it kicks in. Home Depot's generator guide puts a fridge at 600–800 W running and says motors take about three times that to start (Home Depot). Generac lists a refrigerator at 700 W running plus 2,200 W extra to start, about 2,900 W in total.

Those are cautious figures, which makes them safe for sizing. Our rule is a continuous rating of at least the running watts plus 25%, and a surge rating at least as high as the start-up watts. That gives 1,000 W continuous with about 2,900 W surge, enough to start almost any household fridge. Read the surge (peak) rating on the spec sheet, not only the continuous rating. The full calculator is stricter still and sizes the continuous rating to cover the surge plus 25%, so it will suggest a bigger inverter than this page.

How many solar panels and batteries to run a fridge at night

Solar can run a fridge at night only through a battery. Take the energy for the hours you need, then allow for the share of a lithium iron phosphate (LiFePO4) battery you can use and its efficiency, 90% each:

For the bottom-freezer fridge that's 1.0 kWh for a 12-hour night and 2.0 kWh for a full day with no sun. A top-freezer fridge needs about 0.6 kWh for the night.

Put the two halves together for an off-grid fridge in New York and you get 2 panels (sized for December) and about 2.0 kWh of battery, enough for one dull day. If you get runs of cloudy days, add battery for each one; that's where we'd spend the money before adding panels.

A short power cut is a different case. The USDA says perishable food stays safe in a fridge for about 4 hours with the door closed (USDA FSIS). For an hour or two without power, a shut door does the job. Longer cuts, and evening cuts in hot weather, are where a battery earns its keep.

How many solar plates for a fridge in Pakistan or India?

In Pakistan and India people usually talk about "solar plates", and the usual sizes are 545–585 W, so here are the numbers for a 550 W plate. One plate covers a bottom-freezer fridge on an average day in Lahore, Karachi and Delhi, and even a large French-door model needs at most 2 in the worst month:

Notice the worst month. It isn't winter here but the monsoon, when cloud cuts output. Your fridge will also work harder in a hot kitchen than its label suggests, so treat these as minimums. For load-shedding, the plate is the cheap part; what keeps the fridge running through an evening cut is a battery and a hybrid inverter. Bridging a 4-hour cut takes about 0.3 kWh of battery for the bottom-freezer fridge.

Fridge plus a TV, lights or a deep freezer

Add the daily energy of each appliance. For anything without a yearly kWh label, the DOE formula is watts × hours used a day ÷ 1,000. If your TV's label says 100 W and it's on for 5 hours, that's 0.5 kWh, so fridge and TV together come to 2.1 kWh a day: two 430 W panels in New York and one 550 W plate in Lahore on an average day. Lights work the same way.

A deep freezer is the bigger addition. The bottom-freezer fridge plus a mid-size chest freezer (0.95 kWh, the median certified 14–22 cu ft model in ENERGY STAR data) comes to 2.6 kWh a day: 2 panels in Phoenix, 2 in New York and 3 in London on an average day. Both compressors can start at the same moment, so size the inverter for 2,000 W continuous and about 5,800 W surge. The freezer guide has the same sum with 300 W panels and 550 W plates.

Grid-tied solar: offsetting the fridge, and what happens in a power cut

On a grid-connected home the panels don't feed the fridge directly. They feed the whole house, and the grid covers nights and dull days. The panel counts above then tell you how much solar offsets the fridge's yearly use, and with net metering you don't need a battery for that (see how net metering works).

The catch is outages. Most grid-tied systems switch off when the grid goes down, so they can't feed power into lines that workers may be repairing. If keeping the fridge cold in a power cut is the point, you need a battery or a hybrid inverter with a backup output, and the fridge belongs on that backup circuit.

Common questions

Sources

Solar output for every location comes from the European Commission's PVGIS 5.3 (1 kW system, panels at the best fixed angle facing the equator, 14% system losses), retrieved 20 October 2026. Panel counts assume 430 W panels, the most common size in 2025 home solar quotes (EnergySage).

• ENERGY STAR certified compact refrigerator (Avanti, 3.1 cu ft)
• ENERGY STAR certified top-freezer refrigerator (Criterion, 18 cu ft)
• ENERGY STAR certified bottom-freezer refrigerator (Bertazzoni, 22.5 cu ft)
• ENERGY STAR certified side-by-side refrigerator (Frigidaire, 25.6 cu ft)
• ENERGY STAR certified bottom-freezer refrigerator (Frigidaire, 26.3 cu ft)
• ENERGY STAR certified residential freezers dataset (median of 14–22 cu ft chest models)
• US DOE Energy Saver: estimating appliance energy use
• Home Depot: choosing the right size generator
• Generac RS5500/RS7000E brochure, wattage guide
• USDA FSIS: keep your food safe during emergencies

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