EcoFlow DELTA 2 Max
The EcoFlow DELTA 2 Max is a 2,048 Wh portable power station with 2,400 W of outlets. On one charge it runs a typical fridge about 21 hours and an older furnace blower about 9.6 hours. Both, plus Wi-Fi, lights and phones: about 5.6 hours.
2,048 Wh battery (1,741 usable)2,400 W output4,800 W peak50.7 lb
$591 per usable kWh at Amazon prices checked October 3, 2026 ($1,029 for 1,741 usable Wh). Each added EcoFlow DELTA 2 Max Smart Extra Battery: $516 per usable kWh. How we work it out
Amazon links here are affiliate links: we may earn a commission, at no cost to you. It does not change our numbers. How that works.
Price checked October 3, 2026; Amazon shows today’s price. This is the listing we matched to the bare unit, not a bundle.
- Extra batteries
- Up to 2 DELTA 2 Max Smart Extra Batteries, 2,048 Wh each: 6,144 Wh in all. How far it goes
- Solar
- Up to 1,000 W: two inputs of 500 W, 11–60 V. Panels
- Wall charge
- 1,800 W: 80% in about 1.1 hours
- As a UPS
- Switches to battery in 20–30 ms. Not for computers that need 0 ms. Details
Same battery as the DELTA 3 Max: which one to buy today. Not the recalled DELTA Max (2000): how to tell them apart.
DELTA 2 Max or DELTA 3 Max?
Most people: the DELTA 3 Max, unless you will add a battery. Both hold 2,048 Wh and run 2,400 W. On October 3, 2026 the DELTA 3 Max cost $879 on Amazon, $150 less: $505 per usable kWh against $591. It also switches to battery faster, in 10 ms (EcoFlow). But it takes no extra battery: EcoFlow sells its Max Plus extra battery for the Max Plus and Ultra Plus only (EcoFlow).
Buy the DELTA 2 Max if you may add batteries. It takes two, up to 6,144 Wh. The DELTA 3 Max Plus takes extra batteries too and runs 3,000 W, but costs $1,149 ($660 per usable kWh).
DELTA 2 instead? It holds half (1,024 Wh, 1,800 W) for $599. With one DELTA 2 Max Extra Battery it reaches 3,072 Wh for $1,498. Pick the Max if you need more than 1,800 W at once.
Compare 5 EcoFlow models at today’s prices
| Model | Battery | Output | Extra batteries | Amazon | Per usable kWh |
|---|---|---|---|---|---|
| DELTA 2 Max | 2,048 Wh | 2,400 W | Up to 2 extra batteries, 6,144 Wh total | $1,029 | $591 |
| DELTA 3 Max (2048Wh) | 2,048 Wh | 2,400 W | Not listed by EcoFlow (only the Max Plus) | $879 | $505 |
| DELTA 3 Max Plus (2048Wh) | 2,048 Wh | 3,000 W | Yes, 2-10 kWh with Max Plus extra batteries | $1,149 | $660 |
| DELTA 3 Plus | 1,024 Wh | 1,800 W | Yes, via XT150 port; expandable up to 5 kWh total | — | — |
| DELTA 2 (EFD330) | 1,024 Wh | 1,800 W | Yes, one Smart Extra Battery | $599 | $688 |
Amazon prices checked October 3, 2026. Every EcoFlow model: which EcoFlow to buy.
How long it runs each appliance
A typical fridge runs about 21 hours: 5 hours for an old one working hard, up to 87 for an efficient one. EcoFlow says up to 14 hours (EcoFlow), but that assumes a fridge drawing 120 W the whole time (EcoFlow). A fridge cycles on and off, so we plan on 84 W.
Chart: hours for 8 common appliances
The same numbers as a table
| Appliance | Typical average draw | Hours on one charge |
|---|---|---|
| Fridge | 84 W | about 21 h |
| Furnace blower, older (PSC) | 182 W | about 9.6 h |
| Furnace blower, variable-speed (ECM) | 132 W | about 13 h |
| CPAP | 55 W | about 32 h |
| Sump pump | 136 W | about 13 h |
| Wi-Fi router and modem | 24 W | about 71 h |
| Laptop | 52 W | about 34 h |
All 14 appliances, with starting watts and ranges
| Appliance | Running / starting | Starts it? | Typical | Range |
|---|---|---|---|---|
| Wi-Fi router and modem | 15–40 W | starts it | about 71h | 44–116h |
| Phone charging and small USB devices | 10–40 W | starts it | about 251h | 73–870h |
| A few LED lights | 15–80 W | starts it | about 116h | 29–464h |
| Laptop and monitor | 45–150 W | starts it | about 34h | 12–97h |
| CPAP | 30–100 W | starts it | about 32h | 17–58h |
| Refrigerator/freezer | 100–700 W
starts at up to 2,900 W |
starts it | about 21h | 5–87h |
| Chest freezer | 80–500 W
starts at up to 2,200 W |
starts it | about 34h | 7.7–145h |
| Sump pump | 700–1,500 W
starts at up to 4,500 W |
starts it | about 13h | 3.3–50h |
| Window air conditioner | 500–3,250 W
starts at up to 7,200 W |
may not start a hard-starting one | about 2.4h | 0.7–8.7h |
| Microwave | 800–1,800 W | starts it | about 58 minutes of running time | short bursts |
| Coffee maker | 700–1,500 W | starts it | about 70 minutes of running time | short bursts |
| Television | 40–250 W | starts it | about 32h | 7–145h |
| Garage door opener | 300–800 W
starts at up to 1,800 W |
starts it | about 2 hours of running time | short bursts |
| 12 V compressor fridge (camping) | 25–110 W
starts at up to 320 W |
starts it | about 94h | 32–279h |
Typical is the middle of our range for that appliance. The range runs from a hard-working unit to an efficient one. Microwave, coffee maker and garage door show minutes of running time, because they run in short bursts.
A furnace blower is wired in. Running it needs an inlet or transfer switch fitted by an electrician.
How far it goes with extra batteries
The same numbers as a table
| Setup | Wh | With furnace | No furnace | Fridge only | Amazon price |
|---|---|---|---|---|---|
| DELTA 2 Max alone | 2,048 | 5.6 hours | 13 hours | 21 hours | $1,029 on Amazon: $591 per usable kWh |
| + 1 extra battery | 4,096 | 11 hours | 27 hours | 42 hours | $1,928 on Amazon: $554 per usable kWh |
| + 2 extra batteries (the most) | 6,144 | 17 hours | 40 hours | 62 hours (3 days) | $2,827 on Amazon: $541 per usable kWh |
No furnace (about 130 W): 13 hours on one charge, 40 hours with two extra batteries. Prices: station checked October 3, 2026, extra battery October 3, 2026. It takes two extra batteries at most (manual).
Questions buyers ask
Which extra battery fits?
The DELTA 2 Max Smart Extra Battery, 2,048 Wh, 42 lb (EcoFlow). You can add two (manual). It cost $899 on Amazon on October 3, 2026: $516 per usable kWh, against $591 for the station. The older DELTA Max Extra Battery (2,016 Wh) fits too. The small 1,024 Wh DELTA 2 Extra Battery does not: EcoFlow lists it for the DELTA 2 only (EcoFlow). Extra batteries for every station.
What solar input does it take?
Up to 1,000 W: two solar inputs of 500 W each, 11–60 V and 15 A (manual). Keep each input’s open-circuit voltage (Voc) under 60 V (manual). The MC4-to-XT60 cable is sold separately. EcoFlow says 1,000 W fills it in 2.3 hours (EcoFlow). The Solar Lab did it in about 2 hours in strong sun (The Solar Lab). Which panels fit.
Is it 4,800 watts?
No. 4,800 W is the surge, for a split second while a motor starts. It runs 2,400 W (manual). X-Boost lets heaters up to 3,400 W run at a lower power (manual). The Solar Lab found it struggled with anything over 2,400 W (The Solar Lab).
How long does it take to charge?
From a wall outlet it takes up to 1,800 W (manual): 80% in about 1.1 hours, says EcoFlow (EcoFlow). The Solar Lab took 1.2 to 1.5 hours to fill it (The Solar Lab).
Can it work as a UPS?
Partly. Plug it into the wall and your devices into it. If the power goes out, it switches to battery. EcoFlow’s page says 20 ms (EcoFlow); the manual says within 30 ms (manual). The manual says not to use it for servers or workstations that need 0 ms (manual). The Solar Lab’s switch test went cleanly (The Solar Lab).
Can it power my house through a transfer switch?
Some circuits, yes. EcoFlow says it works with a home transfer switch for partial backup (EcoFlow). It gives 120 V only, so it cannot run a 240 V well pump or dryer. An electrician fits the inlet and switch. Never plug it into a wall outlet. All ways to connect · Which switch fits.
How heavy is it?
About 50 lb (manual), with two handles and no wheels. Each extra battery adds 42 lb.
Where is the manual?
EcoFlow posts it as a PDF: EcoFlow DELTA 2 Max user manual (PDF). The model number on the label is EFD350 (manual).
What testers found
We do not test units ourselves. These testers did.
- The Solar Lab ran it at 2,400 W without trouble (The Solar Lab) and measured 86% inverter efficiency (The Solar Lab). They also took it on a two-night camping trip (The Solar Lab).
- Left on with nothing plugged in, it used about 13.6 W (The Solar Lab). EcoFlow support told Lloyd Chambers it uses 23 W with the AC outlets on and 5 W with them off (WindInMyFace). His advice: turn the AC outlets off when you are not using them (WindInMyFace).
Photos from the Amazon listing we link. Some are EcoFlow’s own graphics.
Specifications
All 12 specifications, with sources
- Model
- EFD350 manual
- Battery
- 2,048 Wh LiFePO4 (about 1,741 Wh usable) manual
- Output
- 2,400 W pure sine wave, 120 V; 4,800 W surge; X-Boost to 3,400 W manual
- Outlets
- 6 AC; 2 USB-C (100 W); 4 USB-A (12 W and 18 W); car outlet (126 W); 2 DC5521 (38 W) manual
- Solar
- 1,000 W in all: two inputs, 11–60 V, 15 A, 500 W each manual
- Wall charge
- 1,800 W, 15 A manual
- Extra batteries
- Up to 2; 6,144 Wh in all manual
- UPS switchover
- Within 30 ms (manual); 20 ms (product page) manual
- Cycle life
- 3,000 cycles to 80%+ capacity manual
- Runs in
- 14–113°F; charges at 32–113°F manual
- Size and weight
- 19.6 × 9.5 × 12 in; 50.7 lb (23 kg) manual
- Warranty
- 5 years EcoFlow
Buying the right one
We link the bare DELTA 2 Max (ASIN B0C4DW17PD, checked October 3, 2026). Search results also show solar bundles, the extra battery on its own, and DELTA 3 models.
Not the recalled DELTA Max (2000). CPSC recalled the EcoFlow DELTA Max (2000), model EFD310, on October 9, 2025: it may overheat and catch fire (CPSC notice).
How to tell them apart: turn the unit over. The recalled one says EFD310 on the nameplate on the underside. The DELTA 2 Max says EFD350. If yours says EFD310, stop using it and contact EcoFlow for the free firmware repair.
No CPSC recall names the DELTA 2 Max in our screen of October 1, 2026. That cannot clear your own unit.
Listings we did not link, and why
| Listing | Why not |
|---|---|
| EF ECOFLOW DELTA 3 Max Portable Power Station, 2048Wh LFP Battery, 2400W | Listing title does not contain the model name 'DELTA 2 Max'. |
| EF ECOFLOW DELTA 2 Max Solar Generator 2048Wh With 400W Solar Panel | Listing is a bundle (solar panel or kit), not the bare base unit our specifications describe. |
| EF ECOFLOW DELTA 2 Max Solar Generator 2048Wh with 220W Solar Panel | Listing is a bundle (solar panel or kit), not the bare base unit our specifications describe. |
| EF ECOFLOW Portable Power Station Delta 3 Classic, 1024Wh 1800W AC | Listing title does not contain the model name 'DELTA 2 Max'. |
| EF ECOFLOW Portable Power Station DELTA 3 Max Plus, 2048Wh, 3000W Output | Listing title does not contain the model name 'DELTA 2 Max'. |
Sources: 8 pages, read October 1, 2026
EcoFlow DELTA 2 Max product page; EcoFlow DELTA 2 Max user manual (PDF); EcoFlow Smart Extra Batteries page; EcoFlow DELTA 2 Max Smart Extra Battery page; The Solar Lab: DELTA 2 Max review; Lloyd Chambers (WindInMyFace): DELTA 2 Max efficiency; EcoFlow DELTA 3 Max series page; EcoFlow extra batteries page. Amazon prices checked October 3, 2026 (stations) and October 3, 2026 (extra battery). Hours of use follow our method: typical appliance draws and 85% of the battery size.
Judged in: Which EcoFlow power station should you buy? (every EcoFlow model compared); The best portable power stations for home backup; The best portable power stations for camping; The best portable power stations for a sump pump; Can a power station run a gas furnace? Yes, with the right hookup.