What Size Generator Do You Need for a Refrigerator?
A refrigerator is the most critical appliance during a power outage. Food spoils. Medicine goes bad. Here’s exactly
how to size a generator to keep your fridge running.
For generator recommendations, see our guide to the Best Solar
Generators for Home Backup.
Quick Answer
Minimum generator size for a refrigerator: 2,000 watts starting / 400-800 watts running.
A typical refrigerator uses 100-400 watts while running, but requires 3x that wattage (800-1,200W) to start the
compressor. Your generator must handle the startup surge.
Refrigerator Power Requirements
| Refrigerator Type | Running Watts | Starting Watts | Daily Energy (kWh) |
|---|---|---|---|
| Compact (3-5 cu ft) | 50-100W | 200-400W | 0.5-1 kWh |
| Standard (18-22 cu ft) | 100-200W | 400-800W | 1-2 kWh |
| Large (25+ cu ft) | 200-400W | 800-1,200W | 2-3 kWh |
| Chest Freezer | 50-100W | 200-500W | 0.5-1.5 kWh |
Generator Sizing for 24-Hour Backup
Refrigerators cycle on and off. They don’t run continuously. A typical fridge runs 8-12 hours per day total.
| Backup Duration | Energy Needed | Recommended Generator |
|---|---|---|
| 12 hours | 500-1,000Wh | Jackery 1000 |
| 24 hours | 1,000-2,000Wh | Bluetti AC200MAX |
| 48 hours | 2,000-4,000Wh | EcoFlow Delta Pro |
| Extended outage | Solar recharging required | Delta Pro + 400W panels |
The Startup Surge Problem
When a refrigerator compressor kicks on, it draws 3-5x its normal wattage for a split second. This is called “inrush
current” or startup surge.
If your generator can’t handle the surge: The generator trips, shuts off, or fails to start the
fridge.
Solution: Choose a generator with peak/surge wattage at least 3x your fridge’s running watts.
| Generator | Continuous Watts | Surge Watts | Can Run Standard Fridge? |
|---|---|---|---|
| Jackery 500 | 500W | 1,000W | ⚠️ Marginal |
| EcoFlow River 2 | 800W | 1,600W | ✅ Yes |
| Bluetti AC200MAX | 2,200W | 4,800W | ✅ Yes, with room to spare |
Solar vs Gas Generator for Refrigerator
| Factor | Solar Generator | Gas Generator |
|---|---|---|
| Noise | Silent | 50-70 dB (loud) |
| Indoor use | ✅ Safe | ❌ CO poisoning risk |
| Fuel | Sun (free) | Gas ($3-5/gallon) |
| Runtime | Limited by battery | Limited by fuel tank |
| Maintenance | None | Oil changes, spark plugs |
Tips to Extend Refrigerator Runtime
- Keep the door closed. Every opening lets cold air escape.
- Pre-freeze water bottles. They act as thermal mass, keeping food cold longer.
- Set temperature to 37°F (fridge) and 0°F (freezer). Colder isn’t always better—it uses more
energy. - Cycle on/off. Run the fridge 1 hour on, 3 hours off. Well-insulated fridges stay cold for
hours.
Recommended Generators for Refrigerators
| Budget | Recommendation | Runtime Estimate |
|---|---|---|
| Under $500 | Jackery 500 (marginal) | 6-10 hours |
| $500-1,000 | EcoFlow River 2 Pro | 12-18 hours |
| $1,000-2,000 | Bluetti AC200MAX | 24-36 hours |
| $2,000+ | EcoFlow Delta Pro | 48+ hours |
Final Sizing Recommendation
For most refrigerators: A 2,000Wh generator (like Bluetti AC200MAX) provides 24+ hours of backup.
Add solar panels (200-400W) to recharge during extended outages. With solar, you can run a refrigerator indefinitely.
For complete generator comparisons, see: Best Solar Generators for Home
Backup.