Specifications checked against manufacturer pages on 2026-08-23.
The EcoFlow DELTA 2 is a 1,024 Wh portable power station in the 1 kWh-class bracket, with a 1,800 W continuous inverter and LiFePO4 cells. This page transcribes the manufacturer’s specifications as they stood on 2026-08-23, turns the capacity into appliance hours, and names the rows EcoFlow does not fill in. Quoted figures carry a source; calculated ones carry a formula.
In short. 1,024 Wh in the 1 kWh-class band: 37.9 Wh per pound; 3,000 rated cycles to 80%. On our assumptions a full-size refrigerator calculates to 16–17 hr, and a 40 W CPAP calculates to 18–21 hr. We could not fill 1 row from EcoFlow’s page. It is listed below, not guessed. This unit has left its maker’s catalog; see the note below. Hours are calculated from rated capacity, never measured.
Check the current price
The link goes to the exact base unit whose specifications are on this page, not a bundle. Amazon prices change daily.
Catalog status, checked 2026-08-23. The EcoFlow DELTA 2’s store listing on the manufacturer’s site now redirects to a newer model, and the unit no longer appears in the manufacturer’s product-series catalog. It has been superseded by the EcoFlow DELTA 3. Its marketing page, with the spec tab we read the figures from, was still online when checked. Retailers may still sell remaining stock. That changes the question from “which is better” to “is a lower price worth buying a model the maker has moved on from” — see Buying a superseded model below.
Who it is for, and who should skip it
Two lists, both drawn from the table further down.
It fits if
- A refrigerator is what you are saving. It clears a 12-hour outage on our assumptions with about 4 hours to spare, and the stated 2,700 W surge covers a roughly 900 W start.
- One night of uninterrupted medical equipment. A 40 W machine without a humidifier runs the night with margin, and the maker states 30 ms on the grid handover. A heated humidifier changes that arithmetic.
- The unit has to move. 27 lb is a two-hands lift rather than a cart job, so car to porch to basement is realistic.
Skip it if
- You want resistive heat. A 1,500 W heater empties this unit in about 0.6 hr. Heat is what batteries are worst at.
- You own a large array already. It takes at most 500 W of solar; panels past that ceiling idle rather than charge it faster.
- You were counting on the furnace. Hard-wired appliances cannot be reached with a cord; that job needs an interlock or transfer switch and an electrician, on any unit.
Every published specification
Each footnote below points at the sentence a figure came from. Two phrases matter: “Manufacturer does not state” means the maker is silent, “Not yet verified by CalmWatt” means we are.
| Specification | EcoFlow DELTA 2 |
|---|---|
| Rated capacity | 1,024 Wh1 |
| Usable capacity (calculated)* | 870–922 Wh |
| Continuous AC output | 1,800 W2 |
| Surge output | 2,700 W3 |
| Full recharge from wall | 80 min4 |
| Cell chemistry | LiFePO45 |
| Rated cycle life | 3,000+ cycles to 80%6,7 |
| UPS switchover | 30 ms8 |
| Expandable | Yes, up to 3,000 Wh9,10 |
| Max solar input | 500 W11 |
| Max AC charging input | 1,200 W12 |
| AC outlets | 613 |
| Highest USB-C port | 100 W14 |
| App control | Yes15 |
| Stated noise | <60 dB16 |
| Warranty | 5 years17 |
| Weight | about 27 lb18 |
| Manufacturer list price when checked | Manufacturer does not state |
* Our calculation, not a published figure: rated capacity × an assumed 85–90% conversion efficiency.
Notes on the figures
- DELTA 2, rated capacity: Capacity 1024 Wh
- DELTA 2, continuous output: 1800W output
- DELTA 2, surge: From the Output section of EcoFlow’s spec tab.
- DELTA 2, full recharge: Stated as 0–100%.
- DELTA 2, cell chemistry: Battery Chemistry LFP (LiFePO4)
- DELTA 2, cycle life: EcoFlow’s DELTA 2 page gives two different figures: ‘3000+’ cycles in the description and ‘4000 cycles to 80%+’ in the spec tab. We use the lower one.
- DELTA 2, cycle life: 80% of its original capacity
- DELTA 2, UPS switchover: UPS 30ms, EPS
- DELTA 2, expandable: Extra Battery ✓
- DELTA 2, expandable: 3 kWh with two extra batteries; 2,048 Wh with one.
- DELTA 2, solar input: Delta 2 can work with one 400W solar panel, or two 220W solar panels used in series, and the maximum solar charging power is 500W.
- DELTA 2, AC input: AC Charging X-Stream Fast Charging 1200W max.
- DELTA 2, AC outlets: Product page Specs tab, ‘Output’ section.
- DELTA 2, USB-C: Not stated as text on the product page (Specs tab only says ‘Number of USB-C Output 2’; the Specs-tab product image shows the printed port label ‘USB-C 100W’).
- DELTA 2, app: Product page FAQ (‘What connection methods do the APP support?’).
- DELTA 2, noise: Product page Specs tab.
- DELTA 2, warranty: Product page Specs tab.
- DELTA 2, weight: Manufacturer states ‘approx.’
What EcoFlow does not state
A specification sheet is as informative in what it omits as in what it lists. Every gap on this unit’s page, named rather than quietly filled in. That places it with the 29 of 34 transcribed units that leave a gap; this one leaves 1 figure.
- A list price. Absent from EcoFlow’s specifications for this unit when we checked.
- Usable capacity. No maker in our database publishes one. Rated capacity is the cells; what reaches the outlet is less, and the gap moves with the load.
None of this makes the unit worse than its rivals; most makers omit most of these. It does mean any page quoting a confident number for one of them is quoting an estimate.
What it runs, and for how long
Same appliances and assumptions we use on every comparison page, so these rows read against any other unit on this site.
| Appliance | DELTA 2 |
|---|---|
| Full-size refrigerator 150 W, 900 W start, 35% duty · eff. 80%–87% |
16–17 hr |
| Mini fridge 70 W, 400 W start, 30% duty · eff. 70%–82% |
34–40 hr |
| CPAP without humidifier 40 W · eff. 70%–82% |
18–21 hr |
| CPAP with heated humidifier 95 W · eff. 80%–87% |
8.6–9.4 hr |
| Gas furnace blower 400 W, 1600 W start, 40% duty · eff. 85%–90% |
5.4–5.8 hr |
| 1/3 hp sump pump 500 W, 1800 W start, 15% duty · eff. 85%–90% |
about 12 hr |
| Router and modem 20 W · eff. 70%–82% |
36–42 hr |
| Laptop 60 W · eff. 70%–82% |
12–14 hr |
| 1500W space heater 1500 W · eff. 82%–88% |
about 0.6 hr |
Arithmetic, not a measurement: hours = rated Wh × efficiency ÷ (appliance W × duty). Appliance and efficiency assumptions live on How we verify. A row reading “Unlikely to start” failed the surge check, not the capacity one.
The same specs, normalized
| Measure | DELTA 2 |
|---|---|
| Cost per watt-hour | Not available — EcoFlow does not state a list price. |
| Watt-hours per pound | 37.9 Wh/lb |
| Surge headroom | 1.50× |
| Recharge rate | 12.8 Wh/min |
| Rated cycle life | 3,000 cycles to 80% |
| Continuous watts per dollar | Not available — EcoFlow does not state a list price. |
Ratios have no winner here — there is no second column. Each one is defined, with its direction, on How we verify.
What those figures actually mean
Watt-hours per pound: 37.9 Wh/lb. 1,024 Wh in 27 lb makes this a two-hands lift. Density is what lithium iron phosphate gives up to older chemistries; the cycle rating is what it buys in return.
Surge headroom: 1.50×. A stated 2,700 W surge over a 1,800 W continuous rating, which covers the roughly 900 W a full-size refrigerator needs to start. Capacity is irrelevant if the motor never turns.
Recharge rate: 12.8 Wh/min. A full wall charge in 80 minutes. In a multi-day outage this is generator fuel measured in minutes.
Rated cycle life: 3,000 cycles to 80% capacity. Cycled weekly it would take about 58 years to get there, so for a few outages a year the cell count is not the limit. For daily off-grid use it is. The percentage matters as much as the count: two ratings only compare when they name the same remaining capacity.
Where it sits in our database
The obvious missing question on a one-unit page is whether these numbers are good. Here is where each lands among the units we have verified.
| Measure | DELTA 2 | Among verified units |
|---|---|---|
| Rated capacity | 1,024 Wh | 22nd largest of 34 |
| Continuous AC output | 1,800 W | 21st highest of 34 |
| Watt-hours per pound | 37.9 Wh/lb | 15th densest of 34 |
| Weight | 27 lb | 14th lightest of 34 |
A low rank on weight is a high rank on portability. Nothing in this table is a verdict.
Three outages, and the figure that decides each
- One night, one CPAP. A 40 W CPAP without a humidifier calculates to 18–21 hr. The stated 30 ms handover is what decides whether the machine notices the outage.
- Twelve hours, one refrigerator. A typical full-size refrigerator calculates to 16–17 hr, and the stated 2,700 W surge covers its roughly 900 W start.
- The loads people forget. A gas furnace blower calculates to 5.4–5.8 hr and a one-third horsepower sump pump calculates to about 12 hr. Neither is a cord-and-plug load in a typical house, whatever these hours say. A router and modem, meanwhile, calculates to 36–42 hr.
- Three days, with something to recharge from. A full wall recharge takes 80 minutes, and it accepts up to 500 W of solar, so day two turns on your panels and your sky.
The DELTA 2 against other units
4 pages on this site compare the DELTA 2 directly with another unit, using the table above on both sides.
- Anker SOLIX C1000 vs EcoFlow DELTA 2
- Bluetti AC180 vs EcoFlow DELTA 2
- EcoFlow DELTA 2 vs EcoFlow DELTA 3
- EcoFlow DELTA 2 vs Jackery Explorer 1000 v2
Questions people ask about the DELTA 2
Answers use only the figures on this page.
How long will the DELTA 2 run a refrigerator?
16–17 hr on our assumptions for a typical full-size unit at 150 W running and a 35% duty cycle. The stated surge covers the roughly 900 W start. Your own compliance label is the number that matters.
Can the DELTA 2 run a CPAP all night?
Yes on capacity: a 40 W machine without a humidifier calculates to 18–21 hr against the eight hours a night usually needs. The maker states 30 ms on the handover. A heated humidifier roughly doubles the draw.
How long does the DELTA 2 take to recharge?
80 minutes from a wall outlet on the maker’s figure, with up to 500 W accepted from solar. In a long outage that sets how long a generator runs per refill.
How much does the DELTA 2 weigh?
27 lb on the maker’s figure, or 37.9 Wh of rated capacity carried per pound. That is a two-hands lift, which is why units this size tend to stay where you put them.
How many cycles is the DELTA 2 rated for?
3,000 cycles to 80% of original capacity, on LiFePO4 cells, which is roughly 58 years at one cycle a week. Compare it only with ratings quoted to the same remaining capacity.
Can you expand the DELTA 2’s capacity?
Yes, to a stated 3,000 Wh with the maker’s expansion battery, up from 1,024 Wh alone. Confirm the matching battery is on sale before counting on it.
Check the current price
The link goes to the exact base unit whose specifications are on this page, not a bundle. Amazon prices change daily.
Buying a superseded model: what actually changes
Nothing in the table above changes because a model leaves the catalog. The cells, the inverter and the cycle rating are what they were. Three things do change.
- Price, and therefore cost per watt-hour. A superseded unit is only a bargain if its lower price beats the successor on cost per watt-hour and the successor’s advantages are ones you will not use. Compare against the successor’s figures (see our DELTA 2 and successor comparisons on the Comparisons page). If the successor’s surge or UPS figure is the one your outage tests, the discount is buying you the wrong unit cheaply.
- Warranty and support. The manufacturer states a 5-year warranty for the DELTA 2. Check with the retailer that the term runs from your purchase date, not the model’s launch date. How long firmware and app support continue for a retired model is not something we could verify from the manufacturer’s pages; if the app matters to you, ask before buying.
- Expansion batteries. If you expect to add capacity later, confirm the matching expansion battery is still sold. Successor batteries are not always backward-compatible.
Our rule: compare the discounted price against the successor on cost per watt-hour first. If the superseded unit does not win there, the rest does not matter.
Related reading
Against a gasoline generator this loses on endurance — a 1,500 W space heater empties it in about 0.6 hr — and wins on the one thing that kills people every winter. Our CPSC revision matrix tracks how the official count of generator carbon-monoxide deaths has changed across report editions, and this page puts every verified unit, including this one, on one refrigerator scenario.
Ordering before a storm? Check the arrival date at checkout — a unit that ships tomorrow can beat a better one that ships next week. Amazon Prime includes fast delivery on eligible items and starts with a free trial; we earn a commission if you join.
Sources and method
- EcoFlow DELTA 2: manufacturer product page, checked 2026-08-23.
We compared published specs and copied each figure from the manufacturer’s page. Runtimes are our arithmetic, not a measurement, and the formula is on the page so you can substitute your own load. Method: How we verify. More: Comparisons.