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How to Size a Generator for Your Home
Formula
Add up running watts of all appliances you need simultaneously. Then add the highest single starting surge.
Choose a generator rated at least 20% above your total starting wattage.
Common use cases:
- Size a backup generator for outages
- Plan generator needs for events
- Check if your generator handles your loads
Frequently Asked Questions
Dr. David Park
Applied Mathematician, PhD Mathematics
David holds a PhD in Applied Mathematics from MIT. He has published research on numerical methods and computational algorithms used in engineering and scientific calculators.
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