Generator Size Calculator: What Size Generator Do I Need?
Calculate the right generator size by entering your electrical appliances and requirements below.
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List of the Top 10 Best Generator:
Understanding Generator Sizing
Choosing the right size generator is crucial for reliable power backup. A generator that's too small won't meet your needs, while one that's too large wastes fuel and money.
Generator Types and Uses
| Type | Size Range | Best For |
|---|---|---|
| Portable Inverter | 1,000-4,000W | Camping, RV, small appliances |
| Portable Generator | 3,000-8,000W | Job sites, home backup |
| Large Portable | 7,000-15,000W | Whole house partial backup |
| Standby Generator | 12,000-45,000W | Whole house full backup |
Common Appliance Power Requirements
| Appliance | Running Watts | Starting Watts |
|---|---|---|
| Refrigerator | 600-800W | 1,200-1,600W |
| Air Conditioner (10,000 BTU) | 1,500W | 2,200W |
| Sump Pump | 800-1,100W | 1,300-2,200W |
| Well Pump | 1,000-2,100W | 2,000-4,200W |
| Electric Water Heater | 4,000-4,500W | 4,000-4,500W |
Important Factors in Generator Sizing
1. Power Requirements
Consider these factors when calculating power needs:
- Running watts vs. starting watts
- Simultaneous usage requirements
- Essential vs. non-essential appliances
- Future power needs
2. Usage Type
Different applications require different considerations:
- Emergency home backup
- Construction site power
- Recreational use
- Full-time power generation
3. Fuel Type
Available options include:
- Gasoline
- Propane
- Natural Gas
- Diesel
- Dual Fuel
Generator Maintenance and Safety
Essential Maintenance Tasks
- Regular Checks:
- Oil level and condition
- Fuel system maintenance
- Air filter inspection
- Battery testing
- Periodic Maintenance:
- Oil changes
- Spark plug replacement
- Fuel filter replacement
- Generator exercise schedule
Frequently Asked Questions About Generator Sizing
How do I determine my power needs?
To calculate your power requirements:
- List all essential appliances
- Note both running and starting watts
- Consider simultaneous usage
- Add 20% for future expansion
What's the difference between running watts and starting watts?
Understanding power requirements:
- Running watts: continuous power needed to operate
- Starting watts: extra power needed at startup
- Most motor-driven appliances need 2-3x running watts to start
- Generator must handle highest combined starting watts
Should I choose a portable or standby generator?
Consider these factors:
- Portable Generators:
- Lower cost
- More versatile
- Manual operation
- Limited power output
- Standby Generators:
- Automatic operation
- Higher power output
- Permanent installation
- Higher cost
What fuel type should I choose?
Fuel considerations include:
- Availability during emergencies
- Storage requirements
- Cost efficiency
- Environmental impact
- Local regulations
How often should I maintain my generator?
Maintenance schedule:
- Monthly: Test run and visual inspection
- Every 3 months: Check oil and filters
- Annually: Comprehensive service
- Before/after storage: Full maintenance check
Is professional installation necessary?
Installation considerations:
- Required for standby generators
- Electrical connections must meet code
- Transfer switch installation
- Proper ventilation and placement
- Warranty requirements
What safety features should I look for?
Important safety features include:
- Low-oil shutdown
- Circuit protection
- Carbon monoxide detection
- Automatic voltage regulation
- Weather protection
How long will a generator run on a tank of fuel?
Run time depends on:
- Fuel tank size
- Load percentage
- Fuel efficiency
- Generator size
- Type of fuel used
Can I power my whole house with a generator?
Whole house considerations:
- Total power requirements
- Essential vs. non-essential circuits
- Transfer switch capacity
- Generator sizing
- Cost implications
What's the best way to store a portable generator?
Storage guidelines:
- Clean and dry location
- Fuel stabilization or drainage
- Battery maintenance
- Regular exercise schedule
- Protection from elements