How long can the EcoFlow DELTA Pro 3 run a Router + modem?
7.3 dayswell beyond what you asked for
Formula: (4.1kWh × 0.85 inverter efficiency) ÷ 0.48 kWh/day = 7.3 days. At continuous 20 W draw (no duty cycle), about 7.3 days.
What if you add a battery? The + Extra Battery config jumps to 8.2kWh — roughly 14.5 days on a Router + modem.
Appliance
Router + modem · 20 W / 20 W surge
Battery (base)
4.1kWh · 4kW / 8kW surge
Some links may be affiliate links. GridMatch may earn a commission if you buy through them, at no extra cost to you.
Runtime Quick-Check
Runtime Quick-Check
Pick a battery and an appliance — see days of runtime after the 0.85 inverter derate.
7.3 days
Formula: (4096 Wh × 0.85) ÷ 0.48 kWh/day = 7.3 days. Continuous draw ≈ 7.3 days at full load.
Nearest alternatives
Running more than one device?
Open sizing wizard