TALK TO AN EXPERT: 1-844-945-3625
TALK TO AN EXPERT: 1-844-945-3625
by Saxon Funk 9 min read
The EcoFlow Delta Pro is a 3,600Wh, 3,600W portable power station that expands to 25kWh. This review covers what it does well, where it shows its age, and who should buy it in 2026.
What Can a Delta Pro Run, and for How Long?
Delta Pro Batteries, Solar Charging and Care
Delta Pro Setup, Accessories and Smart Home Panel
The EcoFlow Delta Pro launched in 2021 as the first portable power station that could honestly be called a home battery, and it remains the model that defines the 3 to 4 kilowatt-hour class. It stores 3,600Wh, delivers 3,600W continuously with a 7,200W surge, accepts 1,600W of solar, and grows to 10.8kWh with two extra batteries or 25kWh in a two-unit Smart Home Panel system. Newer EcoFlow models charge faster and the DELTA Pro 3 and Delta Pro Ultra go bigger, but at $1,899 the Delta Pro is still the most cost-effective way into serious backup power. This review covers what it does well, where it shows its age, and who should buy it in 2026.
| Capacity | 3,600Wh; expandable to 10.8kWh with two Smart Extra Batteries; 25kWh in a two-unit Smart Home Panel system |
| Chemistry | LFP (LiFePO4); 3,500 cycles to 80%, 6,500 cycles to 50% |
| AC output | 3,600W continuous, 7,200W surge; X-Boost to 4,500W; two units paired deliver 7,200W and 240V |
| Ports | AC outlets, 2 Γ USB-A, 2 Γ USB-A fast charge, 2 Γ USB-C 100W, 12V car port 126W, 2 Γ DC5521, Anderson port |
| AC charging | 1,800W from a wall outlet; up to 6,500W with MultiCharge (AC plus solar plus Smart Generator) |
| Solar input | 1,600W max; full in about 2.25 hours at full input |
| Other inputs | EV charging station port, 12/24V car charging, EcoFlow Smart Generator |
| Shelf life | About 1 year after a full charge |
| Weight | 99 lbs (45 kg), with wheels and a telescoping handle |
| Connectivity | Wi-Fi and Bluetooth app control |
| Price | $1,899 alone; $2,959 with a Smart Extra Battery; $4,399 with a Smart Generator or Wave 2 |
Specifications and prices are from the current Wild Oak Trail product page.

EcoFlow began as a Kickstarter company. The original Delta raised millions in 2019, and the Delta Pro campaign in 2021 raised over $12 million, at the time one of the largest technology crowdfunding campaigns ever. The pitch was simple: a portable power station large enough to back up a house, expandable enough to grow with you, and clean enough to run indoors.
Before the Delta Pro, a "portable power station" meant a 500 to 1,500Wh box for camping. After it, the category included units that could run a refrigerator, a well pump and a furnace blower through a multi-day outage. Every large EcoFlow since, including the DELTA Pro 3, Delta Pro Ultra and Delta Pro Ultra X, builds on the idea the Delta Pro proved.
The base unit holds 3,600Wh, about three times a typical 1kWh camping power station. On its own that runs a full-size refrigerator for about two days, a CPAP for a week of nights, or a 1,500W space heater for about two hours. Our runtime guide works through dozens of appliances.
Where the Delta Pro pulls away from the pack is expansion. Each Smart Extra Battery adds another 3,600Wh, and a single Delta Pro accepts two of them for 10.8kWh, all managed as one system through the same inverter. Pair two Delta Pro units through a Double Voltage Hub or the Smart Home Panel and you have 7,200W of output, 240V for a dryer or well pump, and up to 25kWh of storage. That is a system that can carry a typical home's essential loads for several days without solar. Our extra battery guide explains when the second and third batteries are worth it.
The Delta Pro's pure sine wave inverter delivers 3,600W continuously and handles 7,200W surges, which is enough to start and run almost any 120V appliance in a home, including central air handlers, electric dryers on a 120V adapter, well pumps, table saws and welders in the small-to-mid range. X-Boost lets resistive loads up to 4,500W run by trimming voltage slightly, so a large space heater and a kettle can share the unit. Two paired units give you 7,200W and true 240V.
The port selection covers everything: multiple AC outlets, two 100W USB-C ports for laptops, fast-charge USB-A, a 12V car port, DC5521 barrel jacks and an Anderson port for high-current 12V loads like an RV fridge or a 12V water pump. In practice the only thing owners run out of is AC outlets during an outage, which a power strip solves.
The Delta Pro takes 1,800W from a standard wall outlet, which fills it in under two hours. It also charges from EV charging stations through a dedicated port at up to 3,400W, from a vehicle's 12V system, from the EcoFlow Smart Generator at 1,800W, and from up to 1,600W of solar. Combine sources through MultiCharge and input reaches 6,500W, which refills the whole 3.6kWh in about 35 minutes. That charging flexibility is a large part of why the Delta Pro works as a home battery: during an outage it can sip from a small generator and a few panels at the same time and never run dry.
Solar deserves its own mention. At 1,600W the Delta Pro accepts more panel input than anything else in its price range, and a full solar recharge takes about 2.25 hours in good sun. Four 400W panels, or a rigid rooftop array through an MC4 adapter, turn it into a small off-grid power plant. Our solar and battery guide covers panel choices and wiring.

The Delta Pro was one of the first large power stations built entirely on lithium iron phosphate cells, and it is the reason units sold in 2021 are still in daily service. EcoFlow rates the cells at 3,500 cycles to 80 percent capacity and 6,500 cycles to 50 percent. Charged and discharged once a day, that is roughly ten years before capacity noticeably fades and nearly eighteen before it halves. LFP is also thermally stable, which is why the Delta Pro is safe to run indoors and to store in a garage that sees summer heat.
Two habits extend its life. Keep it between about 20 and 80 percent when it is sitting idle for long stretches, and recharge it at least every few months in storage; EcoFlow lists a one-year shelf life after a full charge. Avoid leaving it in a hot vehicle or an unheated shed in deep winter. The app lets you set charge limits to make the first habit automatic.
The EcoFlow app connects over Wi-Fi or Bluetooth and shows real-time input and output, battery percentage, estimated time to empty or full, and per-port control. You can set charging speed, which is handy on a shared circuit or to charge gently for battery longevity, set a charge ceiling, and, with a Smart Home Panel, decide which household circuits get priority as the battery drains. During an outage the ability to check remaining runtime from your phone while the unit sits in the garage is the feature owners mention most.
It is heavy. At 99 lbs you do not lift a Delta Pro; you roll it. The built-in wheels and telescoping handle make moving it across a garage floor or a driveway easy, but stairs and truck beds are a two-person job. For a unit that lives in one place and gets rolled to a doorway when the power goes out, that is fine. For a unit you want to carry to a campsite, it is the wrong tool; look at the DELTA 3 Plus or DELTA 3 Max instead.
Fan noise under heavy load is noticeable, more so than on the 2026 DELTA 3 units with their stepless fans. At modest loads the Delta Pro is quiet enough for a living room. The display is bright and legible, the ports are logically grouped, and the unit's rigid, low-center-of-gravity design means it does not tip when rolled over a threshold.
| Model | Capacity | Output | Max system | Price |
|---|---|---|---|---|
| DELTA 3 Ultra | 3,072Wh | 3,600W | Not expandable | $1,499 |
| Delta Pro | 3,600Wh | 3,600W | 10.8kWh single; 25kWh paired | $1,899 |
| DELTA Pro 3 | 4,096Wh | 4,000W, 120/240V | 48kWh | $2,799 |
| Delta Pro Ultra | 6,144Wh per battery | 7,200W, 120/240V | 90kWh | $2,799 inverter; $4,199 with 1 battery |
| Delta Pro Ultra X | 6.1kWh per battery | 12kW, 120/240V | 184kWh | $3,799 inverter; $7,999 with 2 batteries |
The DELTA 3 Ultra is the newer, cheaper, lighter unit with the same 3,600W output; buy it if you never want to expand. The DELTA Pro 3 is the direct successor with 240V on a single unit and much faster charging; buy it if you want one box that does home backup with a smart panel. The Delta Pro sits between them as the most affordable expandable 3.6kWh platform. See every EcoFlow model compared for the full picture.
Wild Oak Trail stocks the Delta Pro alone and in bundles with a Smart Extra Battery, Smart Generator or Wave 2 air conditioner, and we price match. Browse the EcoFlow collection or call or chat with us to configure a system.
Yes, for buyers who want expandable home-backup capability at the lowest price. At $1,899 it offers 3,600Wh, 3,600W and expansion to 10.8kWh on one unit or 25kWh paired. Newer models charge faster or go bigger, but none offers this much expandable capacity for less.
The LFP battery is rated for 3,500 charge cycles to 80 percent capacity and 6,500 cycles to 50 percent. Used once a day, that is about ten years before noticeable fade. Units sold at launch in 2021 remain in daily service.
One unit runs a home's essential loads such as a refrigerator, freezer, lights, internet, furnace blower and medical equipment through an outage. Two units with a Smart Home Panel deliver 7,200W and 240V and can run most of a typical home, including a well pump or dryer.
About 99 lbs (45 kg). It has built-in wheels and a telescoping handle, so it rolls easily on flat surfaces but is a two-person lift for stairs or a truck bed.
Under two hours from a wall outlet at 1,800W, about 2.25 hours from 1,600W of solar, about 1.7 hours from an EV charging station, and as little as 35 minutes using MultiCharge to combine sources up to 6,500W.
The DELTA Pro 3 has 4,096Wh, 4,000W output, 120/240V from a single unit, 2,600W of solar input, faster charging and expansion to 48kWh, for $2,799. The Delta Pro has 3,600Wh, 3,600W, 1,600W solar and expansion to 10.8kWh single or 25kWh paired, for $1,899.
Saxon Funk, co-founder and driving force behind Wild Oak Trail, embodies the spirit of self-sufficiency and preparedness. Launching the venture over six years ago with his wife, Hailey, Saxon has steeped himself in mastering solar generators, heating solutions, food storage, and off-grid living essentials, becoming a veritable guru in the field. His expertise is more than theoretical; it's practical, as evidenced by his own home, equipped with the very products Wild Oak Trail proudly offers. Saxon's passion extends beyond commerce; he thrives on the assurance of providing for his family in any circumstance, fervently believing in empowering others to do the same through the quality resources and knowledge he shares through his business.
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