How long can the Bluetti AC300 + B300K run a Router + modem?
4.9 dayswell beyond what you asked for
Formula: (2.8kWh × 0.85 inverter efficiency) ÷ 0.48 kWh/day = 4.9 days. At continuous 20 W draw (no duty cycle), about 4.9 days.
What if you add a battery? The AC300 + 2× B300K config jumps to 5.5kWh — roughly 9.8 days on a Router + modem.
Appliance
Router + modem · 20 W / 20 W surge
Battery (base)
2.8kWh · 3kW / 6kW surge
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Runtime Quick-Check
Runtime Quick-Check
Pick a battery and an appliance — see days of runtime after the 0.85 inverter derate.
4.9 days
Formula: (2765 Wh × 0.85) ÷ 0.48 kWh/day = 4.9 days. Continuous draw ≈ 4.9 days at full load.
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