Reviews

Adaptability: The Best Thing About the EcoFlow Delta 2 Max Solar Generator

Sure, it stores enough electricity to power a refrigerator for a day and boasts a 10-year lifespan, but endless charging, storage, and deployment possibilities make this system even more valuable.
Mark Wolfe Avatar
The solar panel of the EcoFlow Delta 2 Max solar generator hooked up to the portable power station in a yard
Photo: Debbie Wolfe for Bob Vila

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When the power goes out, we have options. Prior generations weren’t just inconvenienced; they also had to deal with the rapid spoiling of everything in the refrigerator and even dangerous conditions brought on by extreme heat or cold. Thankfully, portable generators have become more affordable and available, and we tested an excellent example. Most generators still rely on gasoline, which comes with its own limitations, such as a safe location to operate and the availability of fuel. It’s hard to pump gas without power.

The current trend in emergency preparedness combines solar power and lithium batteries to store electricity and recharge off the grid. The EcoFlow Delta 2 Max Solar Generator is a nice example of this trend.

EcoFlow creates innovative portable power and renewable energy solutions for home backup, off-grid living, outdoor activities, and other electricity needs. Its product line includes power stations, solar panels, smart generators, and a wide range of accessories. In this review, I’ll share my observations from testing the Delta 2 Max system, including its numerous strengths, a few key weaknesses, and how I incorporated it into my power backup system.

EcoFlow Delta 2 Max Solar Generator: At a Glance

A close-up of the USB ports and display screen of the EcoFlow Delta Max 2 solar generator
Photo: Debbie Wolfe for Bob Vila

Rating: 9.4/10

SPECS

  • Power storage: Lithium iron phosphate (LFP) battery, expandable from 2 to 6 kilowatt hours (kWh)
  • Charging ports: Dual solar input ports, 120-volt AC, 12-volt car outlet
  • Solar panel: 220-watt 12-amp 18.4-volt bifacial solar panel
  • Output: 2,400 watts AC; or 3,400 watts in X-Boost mode
  • Outlets: Six 120-volt AC outlets, 2 USB-A, 2 USB fast charge, 2 USB-C, one 12-volt car outlet, and 2 barrel ports

PROS

  • Power station can charge multiple ways for AC power in emergencies or on the go
  • Easily expandable power storage and solar generation
  • Charges in as little as 43 minutes with simultaneous solar and AC charging
  • Supplies power to as many as 15 devices at the same time
  • Can power a full-size refrigerator up to 14 hours during an electrical outage
  • Solar panel provides reliable charging without fuel or grid electricity, whenever the sun is shining
  • LFP battery has extended lifespan (10 years with daily use) compared to lithium ion

CONS

  • More expensive than a portable gas or dual-fuel generator
  • Does not have a 30-amp outlet to power an RV
  • Sensitive to excessive heat or cold temperatures

Get the EcoFlow Delta 2 Max solar generator at:

What is the EcoFlow Delta 2 Max solar generator?

Those in need of an emergency power backup for home use or a compact solar generator to take on the go will want to take a look at the EcoFlow Delta 2 Max solar generator. This portable power solution comes equipped with a rechargeable power station and trifold portable solar panel to keep electronics charged and appliances running whenever needed.

On its own, the EcoFlow Delta 2 Max portable power station is one of the most robust yet lightweight units of its kind. It features a 2,048-watt LFP battery with a lifespan rating of 3,000 charge cycles above 80 percent capacity, or about 10 years of daily use. The 2,400-watt inverter features 15 electrical outlets to power appliances and electrical devices. The unit features robust protections against overvoltage, low voltage, overload, heat or cold, a short circuit, and overcurrent. It measures 19.5 inches long by 9.5 inches wide by 12 inches high and weighs about 50 pounds.

One of the best attributes of the power station is its flexibility in terms of both charging and delivering power. In addition to dual 500-watt 15-amp solar charging ports, it supports charging from a standard 110-volt 1,800-watt 15-amp household electrical outlet, or using a 96-watt 8-amp 12-volt car outlet. It can even be charged from two sources at the same time.

From a usage standpoint, the Delta 2 Max power station offers 15 different ports that can all run at the same time. The six 120-volt 15-amp AC outlets power up normal devices or appliances you would plug into a standard wall outlet. Two USB-A ports and two USB-A fast-charging ports keep electronic devices running. Two USB-C ports, two barrel ports, and a 12-volt car power port round out the mix.

For additional runtime, the Delta 2 Max lets users add more. Two proprietary ports on the power station allow you to add one or two Delta Max smart extra batteries (sold separately) at 2,016 kWh each, for a maximum total storage capacity of 6,080 kWh.

For those who require remote connectivity, this power station is compatible with the EcoFlow mobile app. With a view to efficiency and security, the app allows you to monitor the charge status, input and output levels, and battery temperature. The app also helps you prioritize AC or solar charging preferences and customize output settings, among other things.

When it comes to charging, the EcoFlow 220-watt bifacial portable solar panel adds a layer of security for home backup or RVing. The quad-fold solar panel comes equipped with an integrated MC4 output controller, charging cables, four corner clips, and a soft-side storage case that doubles as a kickstand for the solar panel. In storage, the panel measures 20 inches long by 1.5 inches wide (thick) by 32.5 inches high; and 72 inches long by 1 inch wide (thick) by 32.5 inches high when unfolded. It weighs 20.9 pounds.

The bifacial solar panel can collect solar energy on both surfaces at an industry-leading 22 to 23 percent efficiency. The front side produces a maximum 220 watts, 18.4 volts, 12 amps; and the rear side delivers up to 155 watts, 18.4 volts, and 8.4 amps. It recharges a depleted power station within a sunny day or two and boosts the charging speed when used in tandem with AC charging. This panel comes prewired for use either alone or in series with additional solar panels.

The EcoFlow Delta 2 Max solar generator next to its solar panel in a yard
Photo: Debbie Wolfe for Bob Vila

Is the EcoFlow Delta 2 Max solar generator easy to use?

With so much flexibility built into the EcoFlow Delta 2 Max system, testing it was sort of difficult, but using it was super easy. Right out of the box, everything was ready, so I started by simply topping off the charge. I used the included wall charging cable to plug into an outlet for the first charge cycle while I familiarized myself with the solar panel, downloaded the app, and explored the app control settings.

Overall, the system was extremely easy to use, but some might consider it a bit too cumbersome to lug around for traveling. It weighs 50 pounds, about the same as a car battery, but it has sturdy rigid handles at both ends to make carrying easier. Those with strength or mobility issues might struggle, especially if additional batteries are part of the equation. A collapsible hand truck could be a good solution to improve portability.

I really liked the ability to monitor input watts, output watts, charge level, and “hours.” The hours reading told me how much time was remaining at the current usage rate—a handy tool if I was trying to plan and conserve battery life.

The only other part of the physical layout that drew my attention was the placement of the various electrical outlets and charging ports. The smaller ports were smartly located beneath the display screen, while the larger AC outlets and input ports were located at the opposite end of the box to reduce tangled cables. The ports to connect additional batteries were located on the side of the unit. Everything was well positioned and easy to locate.

A close-up of the input and output ports on the EcoFlow Delta 2 Max solar generator
Photo: Debbie Wolfe for Bob Vila

Does the EcoFlow Delta 2 Max solar generator produce enough power?

Next, I wanted to deplete the charge as quickly as practical while still using the power station in a real-life scenario. I plugged my refrigerator into one of the outlets and waited for the motor to start. With the motor running, the display screen noted that it had 14 hours remaining. Then, I used one of the USB ports to charge my phone. The display still read 14 hours. I found it fascinating but useful information.

I left the refrigerator plugged in and did nothing special to conserve power. After 6 hours, the charge level was down to about 40 percent. Then, after 10 hours, with about 5 percent charge still showing on the indicator, I stopped the test. This was pretty good backup for a power outage, and much preferable to operating a gas generator all day outside with an extension cord running through the front door.

How fast does the EcoFlow Delta 2 Max solar generator charge?

Altogether, I performed three different test charges: solar only, AC only, and solar combined with AC. Starting with that 5 percent charge, I assembled the solar panel in a wide-open space with full sun exposure all day. The weather was crystal clear and hot (about 90 degrees Fahrenheit). In these conditions, it took a total of 16 hours to top off the charge: noon to sundown (8 p.m.), and sunrise (6:30 a.m.) to 2:30 p.m. During the solar charging period, I repositioned the solar panel every 2 hours to approximate a 90-degree angle. The surface was so hot that I had to wear gloves, and leaving the panel flat on the lawn in midday caused some superficial heat damage to the grass.

After discharging the battery to 6 percent, I plugged it into a wall outlet to charge. It was fully charged within 2 hours and 15 minutes. In the last test, I plugged into an outside wall outlet and hooked up the solar panel for simultaneous charging. Starting at 4 percent, it was fully charged in 1 hour 46 minutes. It also bears mentioning that solar charging while simultaneously using the power station for electricity extends the life of the charge.

Another scenario that occurred to me (and which I have not personally encountered) is the necessity to conserve fuel during an extended outage. For instance, I own a 4,500-watt dual-fuel generator that I have used to power my fridge and other small devices after storms. Combining battery storage could boost efficiency and reliability. As with a hybrid car, fuel economy would improve by recharging the power station for a couple of hours with the gas generator while powering the fridge as well, then switching to the EcoFlow power station alone for the next 10 hours. Adding solar to the charging station reduces charge time and lengthens runtime even more.

The solar panel of the EcoFlow Delta 2 Max solar generator set up in a yard
Photo: Debbie Wolfe for Bob Vila

Is the EcoFlow Delta 2 Max solar generator worth the money? 

If the thought of spending well over $2,000 for a backup solar generator is giving you second thoughts, I’m right there with you. After all, this system generates power slowly, and that’s if the sun is shining. Forget about loading up on solar power on cloudy days. But there are several reasons why I think the EcoFlow Delta 2 Max power station and 220-watt solar portable solar panel is a fair deal and a good buy as an investment in short-term security, starting with the competition.

Jackery sells a similarly equipped package that costs several hundred dollars more. The Jackery Explorer 2000 Plus Solar Generator includes a 2kWh LFP battery, 10 output ports (including a 30-amp outlet), and a 200-watt solar panel. It is similarly expandable, and the power station features a built-in telescoping transport handle and wheels. It’s a really nice setup, but it costs $2,799. If you need a solar generator for camping, it might be worth the extra money; otherwise, EcoFlow Delta 2 might be the better option.

Also, considering the overall flexibility of this equipment, I would not compare it head-to-head with a gas generator. EcoFlow operates with almost zero noise. It works indoors without the risk of carbon monoxide poisoning; it protects sensitive electronics; it is expandable on both the solar generation and power storage ends; and it can work in combination with a combustion generator if one desires.

Is the EcoFlow Delta 2 Max solar generator right for you?

When the power goes out, a backup power supply like the EcoFlow Delta 2 Max solar generator softens the blow. This easy-to-use system comes with everything needed to keep the lights on and the refrigerator running through a short-term outage, and thanks to its compact and relatively portable design, it also comes in handy for travel. But it might not be the right choice for every buyer.

The Delta 2 Max system is designed primarily as a compact home backup system. Although it will keep the fridge running most of the day, those who experience frequent prolonged outages might need something more powerful. One option is to supplement the system with additional EcoFlow smart batteries for increased storage capacity.

Another option is to buy the 3,600-watt EcoFlow Delta Pro power station instead—a better choice for running appliances like microwaves and air conditioners that draw more power. Also, for camping or frequent travel, a portable solar generator on wheels would be more convenient than the wheelless Delta 2 Max.

But anyone looking to augment their independence with an affordable backup power station will want to consider the Delta 2 Max system. It offers tons of flexibility in terms of charging, storage, and supplying electricity when and where it’s needed. The price is better than average for this level of capability, and it comes with features typically found on pricier equipment. It’s a robust solution for basic power needs.

A person holding open the input doors on the EcoFlor Delta Max 2 solar generator
Photo: Debbie Wolfe for Bob Vila

Where to Buy the EcoFlow Delta 2 Max Solar Generator

Get the EcoFlow Delta 2 Max Solar Generator at:

Meet the Tester

Mark Wolfe is a writer and product tester with an extensive background in the nursery and landscaping industries. For more than 20 years he mowed, edged, planted, pruned, cultivated, irrigated, and renovated beautiful landscapes. Now he tests and writes reviews about the latest outdoor power equipment, hand tools, lawn-care products, and other outdoor living goods.

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Mark Wolfe

Staff Writer

Mark Wolfe is a second-career freelance writer based in Georgia and has an extensive background in the horticulture industry. Since 2020, he has contributed numerous gardening and home improvement articles to BobVila.com, along with a variety of consumer product reviews.

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