EcoFlow Delta Pro battery review: maximum solar power for an uncertain world

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It is hard to imagine a day when a 100 pound battery on wheels will cost less than $3,699.

It might be because you want to take out some insurance in the form of emergency backup power now that the public grid is under siege by heatwaves, fires, and floods. Maybe, like me, you just want to take advantage of your employer's new work-from- home policy to disappear into the forest for weeks at a time with a laptop, Starlink RV, Super 73-ZX e-bike, and all the latest gadgets that

You will need a very powerful battery and one that is flexible enough to be refueled at any time. Something similar to the Delta Pro from Eco Flow.

The Delta Pro is a suitcase battery. It can be charged in half a dozen ways including solar panels and from thousands of EV charging stations.

Not only did a 3.6kWh Delta Pro and 400W EcoFlow solar panel keep all my family of five's gear charged for three weeks without dropping below 55 percent, but this big-ass solar generator also proved capable of charging an RV and an entire house.

Since the company launched its first product, I have been covering it. In that time, it has gone from making a single battery to an entire system of products that build upon one another. You start with a single speaker, then a second for real stereo separation, then a soundbar to create a home theater, and finally a sub to amplify the 5.1 sound. You are so locked in that you are not likely to buy anything else.

• 99lbs / 45kg
• 25 x 11.2 x 16.4 inches / 63.5 x 28.4 x 42cm
• 3600Wh capacity LFP battery
• Output: 4x 230V/16A AC outlets (EU) or 4x 120V/20A AC outlets and 1x 120V/30A (US); 3600W total (surge 7200W)
• Output: 2x USB-A 12W max per port and 2x USB-A 18W (fast charge) max per port
• Output: 2x USB-C, 100W max per port
• Output: 1x 12v car socket, 126W max
• Output: 1x 12.6V/30A Anderson Port, 378W max
• Output: 2x 12.6V/3A barrel plugs, 38W max 
• Input: 1x 8A car charging with support for 12V and 24V batteries; 1x 11-150V/15A max solar charging, 1600W max
• Input: AC charger. 120V/1800W max, 240V/3000W max
• Wi-Fi, Bluetooth, and Ethernet connectivity

If you buy one of its flagship 3600Wh Delta Pro batteries, then an EcoFlow expansion battery or two, and then some EcoFlow solar panels, you will be able to charge it all in an eco-friendly way. If you find you aren't using your $10,000 setup all the time, you can fit an EcoFlow smart home panel into your electricity box so that the entire house can still be powered during a temporary power cut, and then add an EcoFlow dual-fuel generator to keep everything powered for Take the gear off the grid to increase the performance of EcoFlow's Power Kits in a remote cabin or RV. If you want to watch the world burn, then kick back with a portable Eco Flow AC unit.

The European version of the Delta Pro is slightly different from the US version. The US model has four standard 120V outlets and one 120V/30A outlet, while the EU model has four 230V outlets and one 120V/30A. It's enough to power just about any major or minor household appliance you throw at it.

The Delta Pro has a new generation LiFePO4 battery which has a number of advantages over traditional batteries. Faster charge times, longer life, lighter weight, and improved safety are some of the things included. If you were to deplete the Delta Pro every day, it would take almost 10 years. The 80 percent mark is reached after just 500 cycles of use.

The Delta Pro has a charge time of 1.8 hours. The figure was achieved by combining multiple charging methods. There are six ways in which the Delta Pro can be charged.

I only tested three of the Delta Pro's six charging methods: regular AC input via shore power while parked at an RV site, the 400W portable solar panel I packed, and from my van's 12v. The review unit didn't come with a type 1adapter that would allow it to charge at up to 3400W while parked at an EV station I couldn't test the EcoFlow Smart Home Panel, which turns the Delta Pro into a short-term battery backup for your home, and the EcoFlow Smart Generator, which will charge the battery at 1700 watt.

I brought a large solar panel for the review. Up to 1600W of solar input from a variety of panel makers can be supported by the Delta Pro. It's not easy to deal with a single panel weighing in at 16 kilograms. I was able to pack it into the rear storage area of the camper because it folds down flat.

The 400W EcoFlow panel and Delta Pro had been tested before. The Delta Pro has a 3.6kWh capacity battery that can be charged at a rate of 10 percent per hour. I enjoyed mostly sunny days on all but a few of the time we were away. 330W could only be achieved with the panels positioned at 90 degrees. Without the help of the solar tracking robot, my charging rate would be closer to 100W because I was too lazy to move the panels.

EcoFlow gives a rough estimate of how long the Delta Pro will last. Based on our testing, these feel right.

There is a home backup.

• 120W AC fridge for 24 hours
• 110W AC 50-inch TV for 27 hours
• 40W AC CPAP machine for up 50 hours

A professional.

• 1650W electric oven for 2 hours
• 1400W AC circular saw for 2.3 hours
• 1080W AC drill for 3 hours

Off grid living in small homes or RV's.

• 6000 BTU air conditioner for about 7 hours
• 60W DC car fridge for 57 hours
• 60Wh USB-C laptop can be charged 57 times

The range anxiety felt by EV owners is similar to the van lifer anxiety. Ecoflow gives you a number of ways to keep on top of your inputs and outputs. The Delta Pro has a display that tells you which ports are active and how much power they use. If you want a dedicated display panel you can mount on a wall, EcoFlow will sell you one. When connected to my mobile hotspot or Starlink RV, I can monitor my power situation from a distance.

I don't know if access to this data reduced my anxiety, but I found it to be addictive. It was a good reminder to align the panels to the sun when the solar input dropped off. For as long as the app is open, the historical graph of inputs and outputs is still maintained. I would like to see a daily archive of that data to better understand my consumption needs.

During my three weeks away, I was able to rely on a 400W panel to keep the Delta Pro charged, and I was able to finish the day with the battery fully charged. I was amazed at how quickly the battery filled when I plugged into shore power. The Delta Pro doesn't have a three-pronged jack, but my shore power cable comes with a two-prong European plug-in. The Delta Pro was plugged into the van's 12v car sockets and I was happy to have it.

My battery never dropped below 55 percent even though I used a lot of devices that needed regular charging.

Much larger devices could be powered by the Delta Pro. I had to plug the Ducato into the EcoFlow battery after the van's recreational battery died while parked in the same spot for a few days. I was able to keep the van's water pump, lights, and two fridges off the grid for more than a day because of the Delta Pro.

The house was plugged into the Delta Pro. A tiny house that is built on its own in the Swedish forest is far away from the public grid. The electrons were fed into the home's bigger battery over the van's shore power cable. During the long Nordic days of summers, the forest house usually gets power from the six 320W solar panels mounted on the roof, but I was traveling with a capable backup solution.

Solar generators can be used indoors, run quiet and green, but diesel generators are usually cheaper and can run for as long as you have fuel, making them a more practical backup for a home in the dark Swedish winters. EcoFlow sells a dual-fuel generator that kicks in if the Delta Pro's battery drops below a threshold. Like I said, the system is called the ecosystems.

• Hank the beagle for scale.
• Delta Pro can also be stood upright.
• Two expansion ports on the back let you connect additional EcoFlow batteries for more output power and capacity.
• The wheels are surprisingly stable on a variety of terrain. But the narrow wheelbase could allow the battery to tip.
• Still portable at 100 pounds.
• No public power grid here, and that’s ok.
• When driving, we kept the battery between the front seats for easy access and to trickle charge it off the car’s cigarette lighter output. Hank would ride and sleep on top of it.
• We kept the Delta Pro in the garage when camping so we could run the solar cable through the window and still lock the van.
• Solar cable snaking into the van.
• Not having to worry about power is truly liberating.
• The panels need regular adjustment to maximize charging rate.
• The Delta Pro easily kept this Super 73 charged while providing constant power to the Starlink RV satellite internet service.
• You can see the solar input history in the app, but the history is lost once the app closes.
• What a good boy.

There are other observations.

• The battery itself isn’t waterproof (you can buy a waterproof cover), but it’s still very durable. We had it parked in between the captain seats where my dog would claw at it and use it for his travel perch. And the wheels stood up to gravel, dirt, and sand while being dragged around by the telescoping handle that never buckled under the stress.
• The Delta Pro’s fast charging inputs create a lot of heat which means its fans can get quite loud. That can be annoying in the confines of an RV or tiny home. It’s much louder than the smaller, slower charging, and less capable Jackery solar generator I reviewed in July. Fortunately, there’s a button on the back of the Delta Pro that can reduce the fan noise, but this also slows down the charging speed. You can also reduce the charging rate in the app by setting it to whatever wattage you prefer.
• As if six charging methods wasn’t enough, EcoFlow has a wind solution “coming soon” for the Delta Pro. That could be a lifesaver in a storm when the sun is blocked out and the power grid is down.
• The app can be buggy at times. For example, setting the max AC input charging rate won’t commit until you kill and reopen the app. But overall, the app is very good, giving you nearly full control over the Delta Pro battery and its ports.

I just returned from a day at the largest RV show in Europe and overheard three people talking about their EcoFlow setup. There are at least one or two that would be a coincidence. I am able to comprehend why.

EcoFlow makes portable power solutions that are suitable for job sites or people who enjoy going off-grid for a weekend or two. Its easy-to-use products can be used as an insurance policy against blackouts, if that is a concern for you in your area.

Products like the $3,699 Delta Pro, which is often on sale for less, and its huge storage capacity, high AC output, portable, insightful app, and wide range of ports and charging options allow people to go further off the beaten path. If you return home, you can use it as an emergency backup power source. It can be really liberating if you don't worry about how you'll keep your devices for work and play.

Thomas Ricker is a photographer.

Every smart device has a set of terms and conditions that you have to agree to before you can use it. It is not possible for us to read and analyze all of them. Since these are agreements most people don't read and can't negotiate, we're going to start counting how many times you have to agree to use the device.

You have to agree to this in order to use the Ecoflow Delta Pro.

• Terms of Use 
• Privacy Policy 
• Products Terms of Use, this agreement states that by using the Delta Pro, you acknowledge that you have read, understood, and agree to be bound by the terms of use and privacy policy, otherwise you can not use the Delta Pro. 

Three mandatory agreements were the final tally.