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The EcoFlow DELTA Pro Ultra X is a 12kW whole-home battery system. It pairs a 12,000W split-phase inverter with 6,144Wh batteries, and the base kit includes two of them for 12,288Wh.
It’s built for backing up a house, not for camping. Here’s what it can run, what else you need to buy, and where testers found trouble.
Specs at a Glance
| Spec | EcoFlow DELTA Pro Ultra X |
|---|---|
| Base kit | 1 inverter and 2 batteries, 12,288Wh |
| AC output | 12kW continuous, 120/240V split-phase |
| Solar input | Up to 10kW, two ports, 80–500V |
| AC charging | Up to 12kW with a 50A connection |
| Expansion | 10 batteries per inverter, 3 inverters (about 184kWh) |
| Outlets | 2 x 120V/20A, one 30A twist-lock, one 50A; no USB |
| Weight | Inverter 70 lb, each battery about 111 lb |
| Protection | IP54, operates from -4°F to 122°F (inverter) |
| Switchover | Under 10ms alone, under 20ms with Smart Home Panel 3 |
| Warranty | 5 years |
What 12kWh Will Run
Usable energy is lower than the label. We’ll assume roughly 10.5–11kWh reaches your loads. That’s our estimate. The system also draws about 36W at idle, per The Solar Lab’s measurement.
| Load | Approx. Runtime (our estimates) |
|---|---|
| Full-size refrigerator, with idle draw | 4–5 days |
| Essentials-only home (8–10kWh a day assumed) | About 1 day |
| 3-ton central air conditioner (about 3,500W) | About 3 hours |
| 1,500W space heater | About 7 hours |
See our guide on whether a solar generator can run an air conditioner for the startup-surge details.
Charging and Solar
This is where the Ultra X stands out. The Solar Lab recharged two batteries in roughly one hour on 12,000W AC, and the solar input hit its 10kW cap without trouble.
The catch is that fast charging needs a 50A connection. The included charging cable is a standard 15A/120V one, which is much slower.
For solar, a 1,600W array (four 400W panels) adds about 5,200–6,400Wh a day (1,600W × 5 sun hours × 65–80%). That’s roughly two days to refill. Our EcoFlow solar panel guide covers the 400W model.
EcoFlow DELTA Pro Ultra X Review
EcoFlow DELTA Pro Ultra X (12,288Wh, 12kW)
The Ultra X gives you a single 12kW inverter, so you can run an air conditioner, an EV charger and the rest of a house on one system. It can also grow, with up to 30 batteries across three inverters.
The catches are cost and complexity. For whole-home backup you also need EcoFlow’s Smart Home Panel 3 (listed at $3,299 on EcoFlow’s site) or a Smart Gateway, plus an electrician. We can’t give an installation price because no source did, so get an itemized quote.
Testers found some rough edges. The Solar Lab saw compressor starts that sometimes caused shutdowns, and one battery caps output at 6,000W, so the full 12kW needs two. In UPS mode, charge and load add together, which can overload a weak source. EcoFlow doesn’t list the older Smart Home Panel 2 as compatible with this model.
Amazon shows 4.1 stars from 375 ratings, shared across the DELTA Pro Ultra family. The review summary is mixed on reliability and charging, and several buyers mention weight. Each battery is about 111 lb.
| Pros | Cons |
|---|---|
| 12kW output from one inverter | High cost, before panel and installation |
| Very fast AC and solar charging | Full 12kW needs two batteries |
| True 50A output | Inconsistent surge handling in one test |
| Expandable to about 184kWh | No USB ports and a proprietary charge cable |
Best for: Homeowners who want a big, expandable backup system and are ready to pay for professional installation.
Full details and current price: EcoFlow DELTA Pro Ultra X (Inverter and 2 Batteries) on Amazon
Full details and current price: EcoFlow DELTA Pro Ultra X with Smart Home Panel 3 on Amazon
Full details and current price: EcoFlow DELTA Pro Ultra X with 4x400W Portable Panels on Amazon
Need more capacity later? Each DELTA Pro Ultra Series 6144Wh Extra Battery plugs into the system.
Think the Ultra X is too much? Read our EcoFlow DELTA Pro 3 review, compare solar generators vs whole-house generators, or see our best solar generator for home backup.
Frequently Asked Questions
What comes in the base kit?
One inverter and two 6,144Wh batteries (12,288Wh) with an AC cable. Smart Home Panel 3 and solar panels are separate unless you choose a bundle.
Do I need an electrician?
For whole-home backup, yes. EcoFlow requires professional installation of the Smart Home Panel 3, and permits may apply. Plug-in use without the panel doesn’t need one.
How many batteries can I add?
Up to 10 per inverter and 30 across three inverters, according to EcoFlow. That’s about 184kWh at the maximum.
Is the Ultra X the same as the DELTA Pro Ultra?
No. The Ultra X offers 12kW from one inverter, versus 7.2kW on the DELTA Pro Ultra. EcoFlow pairs the Ultra X with Smart Home Panel 3, not the Panel 2.
Can it run my whole house?
Possibly, depending on your loads and the circuits you connect. An essentials-only home gets about a day from the base kit, by our estimate.
Final Verdict
The DELTA Pro Ultra X is one of the most powerful single-inverter home backup systems you can buy online, with fast charging and room to grow. Get an itemized installation quote before ordering, since the panel, electrician and extra batteries can add a lot to the base price.