I have tested a lot of portable power stations. I plugged space heaters into them in July, indoors, pointed at my face, in the name of science…and maybe masochism. Until now, the best score I had ever given one was an 89 out of 100. Our EcoFlow Delta 3 Ultra Plus review covers the first generator we’ve tested that received higher than that.
Real capacity: 2,840Wh
I never take a manufacturer’s word for capacity. I plug in a Kill A Watt meter, run a 1,500W space heater until the unit gives up, and see what it actually delivered.
The Delta 3 Ultra Plus put out 2,840Wh of its claimed 3,072Wh for 92% efficiency. Most units I test land in the upper 80s. This is the most efficient portable power station I have measured.
In practice, this capacity powers a refrigerator for 15 hours, a microwave for 4 hours, or a CPAP for 71 hours. To estimate your own gear, divide 2,840 by the appliance’s running wattage.
EcoFlow Delta 3 Ultra Plus Review: The overload test
This unit is rated for 3,600W continuous with a 7,200W surge. For my EcoFlow Delta 3 Ultra Plus review, I pushed well past that with multiple space heaters. It held for about a minute, then shut down two of its four AC outlets and kept the other two running.
That’s unusual and genuinely useful. Almost every other station I’ve tested kills everything at once. If your fridge is on one pair of outlets and you overload another at 2 a.m., that distinction matters.
Recharge, noise, and weight
Zero to 100% on a wall outlet took 2 hours and 37 minutes, near the top of anything I’ve tested. It’s quieter than the space heater it was powering, so it’s fine indoors, in a van, or in an RV.
It weighs 74 lbs, which sounds brutal until you do the math. The Delta 3 Ultra Plus delivers about 41.5 watt-hours per pound, among the best ratios I’ve measured. Wheels and a telescoping handle make it easy to roll. Stairs are another conversation.
What’s missing
No wireless charging pad, which feels like an oversight in 2026. Only one USB-A port, which gets tight fast during an outage. And no 240V output, so a dryer or well pump is out. Instead, that’s Delta Pro 3 territory.
Should you buy it?
At around $1,500 street (ignore the $2,899 MSRP, nobody pays it), yes, you should buy it if you want one strong unit for home backup, RV and van life, or medical equipment like a CPAP. Skip it if you need 240V or plan to carry it anywhere on foot.
Score: 92/100. The best-performing portable power station I’ve tested.
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Check out our EcoFlow Delta Pro 3 review
