Quick answer
Using a planning load of 15W and 85% usable AC energy, the BLUETTI Apex 300 works out to about 156.7 hours of simple calculated runtime for a phone charger. The Apex 300 is rated at 3,840W continuous output, so it clears the basic continuous-wattage check.
What can change the result?
Actual runtime changes with inverter efficiency, battery temperature, state of charge, cable losses, the appliance’s true wattage and — for cycling appliances — how often the compressor or thermostat turns on.
Is the Apex 300 a sensible size for this job?
Yes, based on continuous watts, but you still need to verify startup surge and the exact device rating.
If this is one of several devices you need at the same time, add their watts together and budget their energy consumption across the full backup window.
Bottom line
The calculated 156.7-hour figure is useful for comparing models, but the right buying decision should be based on the exact phone charger, the desired reserve, and your ability to recharge the station.
Compare this against today’s BLUETTI offers
Pricing and bundles change. Verify current specifications, promotions and availability on BLUETTI’s official store before buying.
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