Watts Vs VA when calculating runtime?

Hi there Bluetti community,

When calculating runtime on the AC side of things, should I be using the Watts or the VA being consumed?

I have an AC2A and as noted on a couple of posts on the EB3A, it looks like the display is showing VoltAmps instead of watts on the front of the unit and it appears the runtime calculated is closer to the amount VoltAmps consumed instead of Watts. I was using a fan earlier today with a PF of roughly .5 to draw the battery down a little so the VoltAmps are about twice what the Wattage is. While this fan is going to be replaced with a DC fan within a few days, and I tend to lean heavily towards DC only loads when I can, I’m curious just when I’m doing the spreadsheets - I should be using Watts when calculating runtime correct not VA?

Still love the unit and in most cases I’d be using the fan until the unit said “that’s enough!”. For planning purposes though I’d like to figure out roughly how long it would go to figure out it’s charge breaks in the sun.

The AC output meter on the display is in VA. For runtime calculation you would use the formula listed in the user manual:

Operation time = Battery Capacity (Wh) x DoD x η ÷ (Load Power + AC2A Self-consumption)

Where;

η is the conversion efficiency of the inverter (85% +/- a few)
Self consumption = 12W on AC2A AC inverter.
Example: 50W AC fan with PF of 0.5 (100VA) would show 100W on the display

So 204.8 X 0.90 X 0.85 / 50 + 12W = 2.52Hrs of runtime.

Ok, perfect. Thank you!