Observed arrival · 2026-11-13
Blackout Calc sizes the backup plan
A browser-based calculator estimates generator and power-station needs from the appliances you want to run and for how long.
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ƒJS
- For
- Households planning for power outages
- Worth noticing
- The worked example includes a sump-pump surge and estimates a 5,400 Wh battery for the 24-hour load.
Field notes
The calculation distinguishes simultaneous power demand from energy used over time: the largest single motor surge is added to the running load, while battery capacity is estimated from each appliance’s hours of use. The worked example applies 25% generator headroom, 20% inverter headroom, and a 0.85 battery-and-inverter efficiency factor. It also warns that generators must not run indoors or in a garage because they produce carbon monoxide.
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Editorial observations of this landing page, not a rating.
○OpenPublic substance visible
$PaidCommerce or pricing visible
†AdsAdvertising visible
✦PrettyNotable craft visible
◎NicheUnusually specific use
ƒJavaScriptBrowser-side code central
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