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Blackout Runway: How Long Will It Last?

Enter your generator and fuel on hand, then toggle appliances to watch a live countdown of how many hours your backup power lasts.

🇺🇸 Fuel in US gallons; consumption rates anchored to US generator data.
Your estimated runway
0h 00m
Enter your fuel and flip on appliances below.

1 · Your generator & fuel

A standard gas can is 5 gallons.

2 · AC duty cycle

A higher thermostat setting and a well-insulated home mean the compressor cycles off more, stretching your runway. This is the honest lever — we can't read your thermostat, but you can estimate the duty cycle.

3 · What's running

Running now
0W
Burn rate
0gal/hr

Runtime uses a load-dependent fuel curve (50% load burns ~65% of full-load rate, not 50%) anchored to published US consumption data; your real burn varies with generator model, age, altitude, and temperature. Portable generators shouldn't run continuously without periodic oil checks and cooldowns. A planning estimate; verify against your unit's documentation.