Generator size calculator
Tick what you want to keep running during an outage. You need enough running watts for everything at once, plus headroom for the biggest motor starting.
Backup power options
Quiet and fuel-efficient, with clean power safe for electronics. Runs essentials and a window AC.
See options on AmazonNo fuel and no fumes, safe indoors. Recharges from the wall or solar. Ideal for fridges, CPAP and internet.
See options on AmazonLets a generator feed your panel safely without back-feeding the grid. Have an electrician install it.
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Frequently asked questions
What size generator do I need to run my house?
Add the running watts of everything you want on at the same time, then add the single largest starting (surge) watts on top, since motors briefly draw 2–3× their running power when they start. Essentials only (fridge, freezer, sump pump, lights, internet, microwave) usually fit within a 3,500–5,000 W portable unit. Central AC or an electric range needs 10,000–20,000 W or a whole-home standby generator.
Can a portable power station replace a generator?
For short outages and essentials, yes. A 2–3 kWh battery station runs a fridge for about a day and a CPAP for several nights, silently and indoors. Pair it with solar panels for longer outages. It can't run central AC or electric heat.