All the power you’ll need

Design and features

• Loads of different power outlets
• Large screen with tons of information
• Huge and heavy when moving around

Unlike most power station, such as the Ecoflow Delta 3 Plus, the Delta Pro Ultra isn’t a simple all-in-one unit, and not something that’s especially easy to take with you, unless you’re competing in a strongman competition: the separate inverter and battery unit combined weigh in at a rather hefty 85kg.

This whole home battery is about the size and shape of a small coffee table. Measuring 70x50x50cm, you’ll need to find a dedicated place to store this battery at home. It feels sturdily built and with IP54 protection, it should stay safe from dust and water splashes.  

If you do need to move this power station around, the Delta Pro Ultra comes with a hefty, wheeled trolley for pushing it around on flat surfaces.

You can also make the Delta Pro Ultra even more portable. The version I tested came with a heavy-duty trolley with a sturdy steel frame and chunky black wheels, similar to a sack trolley with a telescopic handle. It turns this heavy lump into something you can genuinely take with you, so long as you don’t need to go up or down stairs.

The unit comes with the inverter section on top and a single battery underneath. The inverter has a large screen showing the current input and output, battery life left in days (yes days) and hours, and a whole host of other useful information.

Underneath are the two high-output 100W USB-C ports, two familiar USB-A ports, four standard UK three-pin plugs, and the all-important 230V, 30A AC output socket that can be used to send power to an entire home via a manual transfer switch (requires professional wiring).

That’s the advantage of splitting the inverter from the battery, as you get a much higher rated output, and can run every type of conventional domestic appliance.

The battery’s capacity is expandable up to five extra batteries stacked up on top of each other. With all five you can store energy up to a massive 30kWh (that’s three to four day’s worth of electricity for a typical home).

That’s not all, and you can also run three separate stacks of inverters and batteries for even the most power hungry setup up to a mind-boggling 90kWh.

The real long term utility of this power station makes itself clear when you connect it to your home. Rather than plugging devices into the range of ports on the front of the inverter, you can have it professionally wired directly into your home circuit and use your plug sockets a normal.

Whether you live in an area that’s prone to power cuts, you want to live off grid, or you want to start generating your own power via solar panels, the Delta Pro Ultra makes it about as easy as possible. Besides getting a competent electrician to wire it into your consumer unit, the process is straightforward.

Charging

• Charge from the mains, solar, or a generator
• Maximum 4,000 Watt solar charging
• Charge the battery to 100% in around 90 minutes

There are lots of ways to recharge the Delta Pro Ultra. On the front is a standard kettle plug port for up to 2800W of charge straight from the grid. Then there are two types of solar to plug in- high and low Voltage. The low-Voltage solar, up to 1600W, plugs into the front of the inverter while the high power, up to 4,000W, has a dedicated port on the side.

You can even top up the battery via a petrol powered generator, in case solar or grid power becomes unavailable, and with an adaptor it will even plug into the 12 Volt socket in your car. For maximum charging power, the Delta Pro Ultra will charge via the grid and solar at the same time, and unlike some power stations, you can still output power while charging using the automatic bypass mode.

With a single battery in place, the maximum charging speed tops out at 6200W, using a combination of solar and mains, which will take the power station from 0 to 100% charge in just over an hour and a half. Just like on the Ecoflow Delta 3 Plus, the charging speeds can be throttled via the app to help protect the battery health and also Time Of Use (TOU) settings that take advantage of off-peak energy prices when charging from the grid.

Testing charging performance using standard mains input, on the maximum charge speed, the EcoFlow Delta Pro Ultra required 6663Wh of power, making the charging a brilliant 92.21% efficient. Dropping the charge input down to 600W, the EcoFlow Delta Pro Ultra managed over 95% efficiency.

Performance

• Class-leading output for a portable power station
• Colossal and expandable capacity of up to 90kWh
• LiFePO4 battery is good for 3,500 charges

The Delta Pro Ultra really shines when you need a large amount of power at once. You can load up to maximum 7200W of power onto the inverter, and output 6900W continuously. That’s enough to run most appliances in a typical home, but off-grid. And with 6 kWh of storage, it could run an average home for a day without recharging, depending on usage.

By taking advantage of the app, you can set the Delta Pro Ultra to run at certain times, look out for extreme weather conditions, and fine-tune charging and output routines depending on what sort of electricity tariff you use.

The app itself is a good-looking thing that feels easy enough to use and gives you instant control over this power station and any other EcoFlow products connected to it. There’s an impressive amount of information available to help you keep an eye on consumption over time, as well as monitor the efficiency of your solar generation. It also allows you to control multiple Ecoflow devices from one place.

Discharging the system under various loads, running between 200W and 2000W, I found that the Delta Pro Ultra delivered 89.29% of its rated capacity over AC at a load of 2000W, and its best efficiency (92.55%) using a 500W load. That’s extremely good, with a lot of power stations delivering closer to 80% efficiency.

Overall, taking the best input rate and best output rate efficiencies, this power station can deliver 88% of the input power it takes over AC as output AC power.

With the standard option (one battery, one inverter), the system retails for £4498. Given that the batteries will last 3500 charge cycles until they hit 80% capacity, that works out a price of £0.23 per kWh stored, which is cheap. Buy a set with two batteries, and the price per kWh stored drops to just £0.17.

The only power station that’s cheaper is the Bluetti Elite 200V2, which costs £0.15 per kWh stored. That power station is considerably smaller and doesn’t have the same kind of power output.

Should you buy it?