EcoFlow DELTA 3 vs EcoFlow RIVER 2 Pro: manufacturer-published specifications compared

EcoFlow DELTA 3 vs EcoFlow RIVER 2 Pro: faster recharge rate vs lighter per watt-hour

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Specifications checked against manufacturer pages on 2026-08-23.

The EcoFlow DELTA 3 (1,024 Wh, 1,800 W) and the EcoFlow RIVER 2 Pro (768 Wh, 800 W), compared on the figures their makers publish. On the normalized ratios, the DELTA 3 recharges at a higher rate (18.3 Wh/min vs 11.0 Wh/min); the RIVER 2 Pro carries more per pound (42.2 Wh/lb vs 37.1 Wh/lb).

In short. The DELTA 3 leads on recharge rate (18.3 Wh/min vs 11.0 Wh/min), rated cycle life (4,000 vs 3,000) and continuous watts per dollar (2.58 W/$ vs 1.51 W/$). The RIVER 2 Pro leads on watt-hours per pound (42.2 Wh/lb vs 37.1 Wh/lb). 2 of 6 measures tie or are not comparable.

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Check the current price

EcoFlow DELTA 3EcoFlow DELTA 3 on Amazon
EcoFlow RIVER 2 ProEcoFlow RIVER 2 Pro on Amazon

Links go to the exact base unit we compared, not a bundle. Amazon prices change daily.

Specifications, side by side

Numbered notes below the table give the source location or a caveat for figures that need one; check marks mark the better figure where one can be judged; “Manufacturer does not state” means absent from that maker’s page as of its check date listed under Sources. UPS switchover is how long the outlets go dark when grid power drops.

Specification EcoFlow DELTA 3 EcoFlow RIVER 2 Pro
Rated capacity 1,024 Wh1 ✓ 768 Wh2
Usable capacity (calculated)* 870–922 Wh 653–691 Wh
Continuous AC output 1,800 W3 ✓ 800 W4
Surge output 3,600 W5 No conventional surge stated (1,600 W boost mode)6
Full recharge from wall 56 min7 ✓ 70 min8
Cell chemistry LiFePO49 LiFePO4 (LFP)10
Rated cycle life 4,000 cycles to 80%+11 ✓ 3,000 cycles to 80%+12,13
UPS switchover <10 ms14 <30 ms15
Expandable Yes, up to 5,000 Wh16 Manufacturer does not state
Max solar input 500 W17 ✓ 220 W18
Max AC charging input 1,500 W19 ✓ 940 W20
AC outlets 621 Manufacturer does not state
Highest USB-C port 100 W22 100 W23
App control Yes24 Yes25
Stated noise <30 dB26 62 dB27
Warranty 5 years28 5 years29
Weight about 27.6 lb30 18.2 lb31 ✓
Manufacturer list price when checked $69932 $52933 ✓

* Calculated: rated capacity × an assumed 85–90% conversion efficiency; no maker publishes a usable figure.

Notes on the figures

  1. DELTA 3, rated capacity: 1024 Wh
  2. RIVER 2 Pro, rated capacity: Rated capacity as stated by the manufacturer; the spec sheet lists Capacity as 768Wh.
  3. DELTA 3, continuous output: 1800W total
  4. RIVER 2 Pro, continuous output: Total continuous AC output across all outlets combined.
  5. DELTA 3, surge: Surge 3600W
  6. RIVER 2 Pro, surge: The stated surge figure equals the X-Boost figure the page markets for running high-wattage resistive appliances such as hair dryers, microwaves, and electric kettles. It is not a conventional motor-start surge rating and should not be read as one.
  7. DELTA 3, full recharge: With the 1,500 W AC input setting.
  8. RIVER 2 Pro, full recharge: Full 0-100% recharge from a wall outlet.
  9. DELTA 3, cell chemistry: LFP (LiFePO4 battery)
  10. RIVER 2 Pro, cell chemistry: The spec sheet lists the cell chemistry as LFP.
  11. DELTA 3, cycle life: 4000 cycles to 80+% capacity
  12. RIVER 2 Pro, cycle life: The manufacturer states this equals roughly 10 years of everyday use.
  13. RIVER 2 Pro, cycle life: The battery is rated to retain at least 80 percent of its original capacity after 3,000 charge cycles.
  14. DELTA 3, UPS switchover: Stated as under 10 ms; an upper bound.
  15. RIVER 2 Pro, UPS switchover: Upper bound. The manufacturer markets this as an EPS auto-switch for essential devices during outages rather than a full UPS.
  16. DELTA 3, expandable: Up to 5kWh
  17. DELTA 3, solar input: DC Charge Input, 11V-60V 500W Max
  18. RIVER 2 Pro, solar input: Maximum solar input, with an accepted voltage range of 11-50 V at up to 13 A.
  19. DELTA 3, AC input: 1500W
  20. RIVER 2 Pro, AC input: Maximum AC wall-charging input power.
  21. DELTA 3, AC outlets: 6 outlets, 1800W total (Surge 3600W)
  22. DELTA 3, USB-C: 2 ports, 100W Max
  23. RIVER 2 Pro, USB-C: The USB-C port is a shared input/output port rated at 100 W maximum in either direction.
  24. DELTA 3, app: APP (TOU / Storm Warning Alert)
  25. RIVER 2 Pro, app: Controlled through the EcoFlow app over Wi-Fi or Bluetooth.
  26. DELTA 3, noise: Stated as under 30 dB at 600 W output and under 40 dB at 1,200 W; an upper bound at a stated load.
  27. RIVER 2 Pro, noise: Upper bound, occurring when charging and discharging at high wattage.
  28. DELTA 3, warranty: 5 years
  29. RIVER 2 Pro, warranty: Stated on the product page as one of the most extended warranties in the industry.
  30. DELTA 3, weight: Manufacturer states ‘approx.’
  31. RIVER 2 Pro, weight: The spec sheet lists net weight as approximately 18.2 lb.
  32. DELTA 3, price: Manufacturer list price when checked; on sale at $569 that day.
  33. RIVER 2 Pro, price: List price; a sale price of $349.00 was shown at the time of capture.

The same specs, normalized

Ratios, so the bigger unit does not win by default.

Measure DELTA 3 RIVER 2 Pro
Cost per watt-hour $0.68/Wh (within 3%) $0.69/Wh (within 3%)
Watt-hours per pound 37.1 Wh/lb 42.2 Wh/lb ✓
Surge headroom Not comparable — the RIVER 2 Pro figure is a boost-mode rating, not a motor-start surge.
Recharge rate 18.3 Wh/min ✓ 11.0 Wh/min
Rated cycle life 4,000 ✓ 3,000
Continuous watts per dollar 2.58 W/$ ✓ 1.51 W/$

Definitions and direction of each ratio: How we verify.

What each one runs, for how long

Appliance DELTA 3 RIVER 2 Pro
Full-size refrigerator
150 W, 900 W start, 35% duty · eff. 80%–87%		 16–17 hr 12–13 hr (start-up not assessed)
Mini fridge
70 W, 400 W start, 30% duty · eff. 70%–87%		 34–42 hr 26–32 hr
CPAP without humidifier
40 W · eff. 70%–87%		 18–22 hr 13–17 hr
CPAP with heated humidifier
95 W · eff. 80%–87%		 8.6–9.4 hr 6.5–7.0 hr
Gas furnace blower
400 W, 1600 W start, 40% duty · eff. 85%–90%		 5.4–5.8 hr 4.1–4.3 hr (start-up not assessed)
1/3 hp sump pump
500 W, 1800 W start, 15% duty · eff. 85%–90%		 about 12 hr 8.7–9.2 hr (start-up not assessed)
Router and modem
20 W · eff. 70%–82%		 36–42 hr 27–31 hr
Laptop
60 W · eff. 70%–87%		 12–15 hr 9.0–11.1 hr
1500W space heater
1500 W · eff. 82%–88%		 about 0.6 hr Will not run

Calculated, not measured: hours = rated Wh × efficiency ÷ (appliance W × duty); assumptions on How we verify. “Unlikely to start”: start-up surge exceeds the stated surge rating. “Start-up not assessed” appears where the start-up draw meets or exceeds the unit’s continuous rating and the unit states no conventional motor-start surge to check it against (RIVER 2 Pro); the hours assume the motor starts.

What the differences mean

Weight for the capacity. The RIVER 2 Pro carries 42.2 Wh/lb against 37.1 Wh/lb for the DELTA 3. Both are two-hands-and-a-flat-surface units; the difference matters if the unit moves between car, porch and basement.

Recharge. The DELTA 3 completes a wall recharge in 56 minutes against 70 for the RIVER 2 Pro — about 14 fewer minutes of generator run time per charge in a multi-day outage.

Cycle rating. The DELTA 3 is rated for 4,000 cycles against 3,000 for the RIVER 2 Pro, both to the same remaining-capacity threshold — otherwise we would not compare them. At one full cycle a week the difference is measured in years, not months; at occasional outage use neither limit is reached.

Output for the money. 2.58 W/$ on the DELTA 3 against 1.51 W/$ on the RIVER 2 Pro: read this row first if the job is powering one heavy load rather than trickling many light ones.

Which one, and for whom

On normalized measures the DELTA 3 leads on recharge rate (18.3 Wh/min vs 11.0 Wh/min), rated cycle life (4,000 vs 3,000) and continuous watts per dollar (2.58 W/$ vs 1.51 W/$). The RIVER 2 Pro answers on watt-hours per pound (42.2 Wh/lb vs 37.1 Wh/lb). Which figure settles it depends on what you need to keep running:

  • CPAP overnight. Switchover: DELTA 3 under 10 ms, RIVER 2 Pro under 30 ms. A 40 W CPAP runs roughly 18–22 hr on the DELTA 3 and 13–17 hr on the RIVER 2 Pro. Both run the night; both switchover figures are upper bounds, so they are too close to call from published numbers.
  • Keeping a refrigerator cold. Check start-up before runtime. The DELTA 3 states a 3,600 W surge rating; the RIVER 2 Pro states a boost figure rather than a motor-start surge rating. A full-size refrigerator needs about 900 W to start.
  • A multi-day outage with a generator or solar to recharge from. Full recharge: DELTA 3 56 min, RIVER 2 Pro 70 min. The faster unit spends less generator fuel per charge.

Check the current price

EcoFlow DELTA 3EcoFlow DELTA 3 on Amazon
EcoFlow RIVER 2 ProEcoFlow RIVER 2 Pro on Amazon

Links go to the exact base unit we compared, not a bundle. Amazon prices change daily.

Related reading

A 768–1,024 Wh battery cannot do what a gasoline generator does — only the DELTA 3’s continuous rating covers a 1,500 W space heater, and it empties in about 0.6 hr — but it also cannot poison a household. The safety half of that trade-off is in our CPSC revision matrix of generator carbon-monoxide death counts, and this page puts every verified unit on the same 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

Published specifications only; no bench tests. Method: How we verify. More: Comparisons.