Portable Generator Size Calculator
Enter the wattage of each appliance you want to power with your portable generator.
List of the Top 10 Best Portable Generators:
How to Calculate Portable Generator Size Requirements?
Finding Appliance Wattage
Accurately determining the wattage needs for your portable generator is essential. Here's how to find appliance wattage:
- Check the Nameplate/Label:
- Look for watts (W) or volt-amperes (VA)
- Check starting/surge watts if listed
- For amps × volts calculations:
- 120V appliances: Watts = Amps × 120
- 240V appliances: Watts = Amps × 240
Common Portable Usage Scenarios
| Usage Type | Typical Needs | Recommended Size |
|---|---|---|
| Camping/RV | Lights, Phone Chargers, Small Appliances | 2,000-4,000 watts |
| Tailgating | TV, Cooling Fan, Small Cooker | 2,000-3,500 watts |
| Job Site | Power Tools, Work Lights | 4,000-7,500 watts |
| Emergency Home Backup | Essential Appliances | 5,000-10,000 watts |
Common Equipment Wattages
| Equipment | Running Watts | Starting Watts |
|---|---|---|
| Electric Grill | 1,500-1,800 | 1,800 |
| RV Air Conditioner | 1,400-2,400 | 2,800-4,800 |
| Mini Refrigerator | 300-400 | 600-800 |
| Circular Saw | 1,200-1,500 | 3,000-4,500 |
| Air Compressor (1 HP) | 1,500 | 4,500 |
| Work Light LED | 100-150 | 150 |
Important Considerations for Portable Generators
1. Portability vs Power
Consider the trade-off between power output and portability:
- Larger generators offer more power but are harder to move
- Inverter generators are quieter but typically offer less power
- Weight ranges from 50 lbs to 250+ lbs
- Consider wheel kits for larger units
2. Runtime and Fuel Efficiency
Fuel consumption varies by load:
- Higher loads consume more fuel
- Eco modes can extend runtime
- Consider fuel tank size
- Plan for refueling needs
3. Noise Considerations
Different environments have different noise requirements:
- Camping: Look for quiet operation (50-60 dB)
- Job Site: Can tolerate louder operation (70-80 dB)
- Residential Use: Consider neighbor impact
Frequently Asked Questions About Portable Generators
What size portable generator do I need for camping?
For camping, a 2,000-4,000 watt portable generator is typically sufficient. This size can handle basic needs like lights, phone charging, small appliances, and even an RV air conditioner. Inverter generators are recommended for camping due to their quiet operation and clean power output.
Can I run power tools with a portable generator?
Yes, but pay attention to both running and starting watts. Most portable generators in the 4,000-7,500 watt range can handle common power tools. Remember that tools with motors need 2-3 times their running watts to start.
How do I determine the right size for emergency home backup?
For emergency home backup, list your essential appliances (refrigerator, lights, few outlets) and add up their wattages. Most homes can manage essential loads with a 5,000-7,500 watt portable generator. Remember that whole-house air conditioning typically exceeds portable generator capacity.
What's the difference between running watts and starting watts?
Running watts is the continuous power needed to keep an appliance running. Starting watts (or surge watts) is the extra power needed to start motor-driven appliances. Your generator needs to handle both, with starting watts typically being 2-3 times higher than running watts.
Should I choose an inverter generator or conventional portable generator?
Inverter generators are better for sensitive electronics and camping due to clean power output and quiet operation, but they're typically more expensive and offer less power. Conventional generators offer more power at a lower cost but are louder and may not be suitable for electronics.