Specifications checked against manufacturer pages on 2026-08-23.
EcoFlow RIVER 3: 245 Wh of LiFePO4 cells behind a 300 W continuous inverter, in the compact size. Checked against the maker’s page on 2026-08-23: every published figure, the runtimes those figures imply, and the specifications EcoFlow does not publish at all. Nothing here is a bench result, and each calculated number says so on its own row.
In short. 245 Wh in the compact band: $0.89/Wh at the list price we recorded; 31.4 Wh per pound; 3,000 rated cycles to 80%. On our assumptions published figures say it is unlikely to start a full-size refrigerator, and a 40 W CPAP calculates to 4.9–5.3 hr. EcoFlow leaves 2 of the rows we track unstated, and we name them rather than filling in a guess. The runtime figures are calculated, not measured.
Check the current price
That link points at the base unit we transcribed, not a kit with panels. Amazon prices change daily.
Who it is for, and who should skip it
The published figures answer this before any opinion does.
It fits if
- The unit has to move. 7.8 lb is a one-hand carry 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 is above the 300 W continuous rating; it will not run.
- A refrigerator through a whole working day. On a typical full-size unit this is unlikely to start; that job wants the next size up.
- Whole-house backup. This is a single-appliance unit, not a standby generator, and it is not wired to your panel.
Every published specification
Numbered notes give the source location or a caveat where a figure needs one. “Manufacturer does not state” marks an absence on the maker’s page; “Not yet verified by CalmWatt” marks one of ours.
| Specification | EcoFlow RIVER 3 |
|---|---|
| Rated capacity | 245 Wh1 |
| Usable capacity (calculated)* | 208–220 Wh |
| Continuous AC output | 300 W2 |
| Surge output | 600 W3 |
| Full recharge from wall | 60 min4 |
| Cell chemistry | LiFePO45 |
| Rated cycle life | 3,000 cycles to 80%6,7 |
| UPS switchover | <20 ms8 |
| Expandable | Manufacturer does not state |
| Max solar input | 110 W9 |
| Max AC charging input | 320 W10 |
| AC outlets | 211 |
| Highest USB-C port | 100 W12 |
| App control | Manufacturer does not state |
| Stated noise | <30 dB13 |
| Warranty | 2 years14 |
| Weight | 7.8 lb15 |
| Manufacturer list price when checked | $21916 |
* Rated capacity × an assumed 85–90% conversion efficiency. Ours, because nobody publishes one.
Notes on the figures
- RIVER 3, rated capacity: Specs tab row. Also in headline bullet: “245Wh capacity, 300W rated output, X-Boost up to 600W”.
- RIVER 3, continuous output: Specs tab row. Headline bullet calls it “300W rated output”.
- RIVER 3, surge: Maker lists a conventional “Surge 600W” and separately an X-Boost mode also rated 600W (“With X-Boost technology, it can power 600W heating devices”); X-Boost is a boost mode for resistive loads, not a surge rating.
- RIVER 3, full recharge: Full 0-100% wall recharge. Body copy: “4 charging options, safely charge 0-100% in 1 hr” / “RIVER 3 fast-charges in 1 hour with X-Stream”.
- RIVER 3, cell chemistry: Specs tab row. Body copy: “LiFePO4 cells, 10-year lifespan”.
- RIVER 3, cycle life: Specs table row ‘Battery Chemistry LiFePO4, 3000 cycles to 80% capacity’; body copy adds: “RIVER 3 has a lifespan of 3000 charging cycles.”
- RIVER 3, cycle life: Battery Chemistry LiFePO4, 3000 cycles to 80% capacity
- RIVER 3, UPS switchover: Upper bound (stated as “<20 ms”). Body copy: “your AC outlet will switch to the RIVER 3 supply in a barely noticeable 20 ms”.
- RIVER 3, solar input: Specs tab row. Body copy: “Power up RIVER 3 in as fast as 2.6 hours with 110W solar input.”
- RIVER 3, AC input: Specs tab row. Generator Input row is also “320W, 0-100% in 60 min”.
- RIVER 3, AC outlets: Specs tab row.
- RIVER 3, USB-C: Single USB-C port, 100W max.
- RIVER 3, noise: Upper bound (stated as “<30 dB”). Body copy: “a volume of less than 30 dB at a distance of 1.5 ft”; footnote 2 says noise data is from lab tests at 89.6°F (32°C).
- RIVER 3, warranty: Not stated on the product page; EcoFlow’s official US warranty-policy page lists the RIVER 3 at 24 months.
- RIVER 3, weight: Specs tab row (net weight). Dimensions row: “10×8.3×4.4 in”.
- RIVER 3, price: Price shown for the standalone RIVER 3 option on us.ecoflow.com when checked; the option was marked “coming soon” and showed no strikethrough price, so we treat $219 as the list price.
What EcoFlow does not state
What a maker leaves out is a fact about the product too. Every gap on this unit’s page, named rather than quietly filled in. Of the 34 units we have transcribed, 29 omit at least one figure; this one omits 2 figures.
- Expandable combo. Absent from EcoFlow’s specifications for this unit when we checked.
- Whether the unit has app control. Absent from EcoFlow’s specifications for this unit when we checked.
- Usable capacity. Nobody states this, here or elsewhere. The rating describes the cells, not the outlet, and the difference depends on what you plug in.
Omissions are the industry norm rather than this maker’s failing. The point is that a confident figure for any of them, anywhere, came from somebody’s guess.
What it runs, and for how long
The appliance set is fixed across the site, which is what makes these hours comparable with any other page here.
| Appliance | RIVER 3 |
|---|---|
| Full-size refrigerator 150 W, 900 W start, 35% duty · eff. 85%–90% |
Unlikely to start |
| Mini fridge 70 W, 400 W start, 30% duty · eff. 85%–90% |
9.9–10.5 hr |
| CPAP without humidifier 40 W · eff. 80%–87% |
4.9–5.3 hr |
| CPAP with heated humidifier 95 W · eff. 85%–90% |
2.2–2.3 hr |
| Gas furnace blower 400 W, 1600 W start, 40% duty |
Will not run |
| 1/3 hp sump pump 500 W, 1800 W start, 15% duty |
Will not run |
| Router and modem 20 W · eff. 80%–87% |
9.8–10.7 hr |
| Laptop 60 W · eff. 85%–90% |
3.5–3.7 hr |
| 1500W space heater 1500 W |
Will not run |
Calculated, not measured: hours = rated Wh × efficiency ÷ (appliance W × duty). Assumptions: How we verify. “Unlikely to start” means the start-up surge exceeds the stated surge rating.
The same specs, normalized
| Measure | RIVER 3 |
|---|---|
| Cost per watt-hour | $0.89/Wh |
| Watt-hours per pound | 31.4 Wh/lb |
| Surge headroom | 2.00× |
| Recharge rate | 4.1 Wh/min |
| Rated cycle life | 3,000 cycles to 80% |
| Continuous watts per dollar | 1.37 W/$ |
A ratio means something only against another unit’s, so pair these with the head-to-head pages below. Definitions: How we verify.
What those figures actually mean
Cost per watt-hour: $0.89/Wh. The $219 list price we recorded over 245 Wh of rated capacity. Capacity alone tells you nothing about value. This does, and it moves every time the price does.
Watt-hours per pound: 31.4 Wh/lb. 245 Wh in 7.8 lb makes this a one-hand carry. These cells are heavier per watt-hour than the ones they replaced, and last far longer. That is the trade the cycle rating prices.
Surge headroom: 2.00×. A stated 600 W surge over a 300 W continuous rating, which is the figure to check against your own appliance’s start-up draw. A unit with hours to spare and no headroom fails in the first second.
Recharge rate: 4.1 Wh/min. A full wall charge in 60 minutes. Over a long outage, refill speed decides how long an engine runs or a cord stays borrowed.
Rated cycle life: 3,000 cycles to 80% capacity. At one cycle a week that is roughly 58 years away, which is another way of saying something else will retire this unit first unless you cycle it daily. The percentage matters as much as the count: two ratings only compare when they name the same remaining capacity.
Continuous watts per dollar: 1.37 W/$. This one moves opposite to cost per watt-hour on most units, so a unit can look good on exactly one of them.
Where it sits in our database
Read against our own database rather than against the maker’s marketing, the figures place like this.
| Measure | RIVER 3 | Among verified units |
|---|---|---|
| Rated capacity | 245 Wh | 34th largest of 34 |
| Continuous AC output | 300 W | 34th highest of 34 |
| Cost per watt-hour | $0.89/Wh | 28th cheapest of 32 |
| Watt-hours per pound | 31.4 Wh/lb | 30th densest of 34 |
| Weight | 7.8 lb | 2nd lightest of 34 |
These positions describe size and price, not fitness for your outage. The row built on price uses the manufacturer list price recorded on 2026-08-23; the retail price behind our link moves independently, so recompute that row against what you are shown.
Three outages, and the figure that decides each
- One night, one CPAP. A 40 W CPAP without a humidifier calculates to 4.9–5.3 hr. The stated under 20 ms handover is what decides whether the machine notices the outage.
- Twelve hours, one refrigerator. Published figures say the compressor is unlikely to start, so the hours never come into play.
- The loads people forget. A gas furnace blower will not run at all and a one-third horsepower sump pump will not run at all. Both are hard-wired in most houses, which makes this an electrician’s question before it is a battery one. A router and modem, meanwhile, calculates to 9.8–10.7 hr.
- Three days, with something to recharge from. A full wall recharge takes 60 minutes, and it accepts up to 110 W of solar, so day two turns on your panels and your sky.
The RIVER 3 against other units
A single unit’s ratios mean little alone. These 2 head-to-head pages put the RIVER 3 against another unit on the same figures.
Questions people ask about the RIVER 3
Every answer below comes from the tables above.
How long will the RIVER 3 run a refrigerator?
Is unlikely to start on our assumptions for a typical full-size unit at 150 W running and a 35% duty cycle. Start-up is the check that comes before hours. Substitute the wattage from the label inside your door.
Can the RIVER 3 run a CPAP all night?
A 40 W machine without a humidifier calculates to 4.9–5.3 hr on our assumptions, against the eight hours a night usually needs. The maker states under 20 ms on the handover. Add a heated humidifier and the hours roughly halve.
How long does the RIVER 3 take to recharge?
60 minutes from a wall outlet on the maker’s figure, with up to 110 W accepted from solar. That is the figure that matters once the outage passes a day.
How much does the RIVER 3 weigh?
7.8 lb on the maker’s figure, or 31.4 Wh of rated capacity carried per pound. That is a one-hand carry, so it moves with you rather than living in one place.
How many cycles is the RIVER 3 rated for?
3,000 cycles to 80% of original capacity, on LiFePO4 cells, which is roughly 58 years at one cycle a week. A figure quoted to a different retention level is a different promise, not a better one.
Will the RIVER 3 run a space heater?
No. A 1,500 W heater is above the 300 W continuous rating.
Check the current price
That link points at the base unit we transcribed, not a kit with panels. Amazon prices change daily.
Related reading
The honest comparison is not with a bigger battery but with an engine: its continuous rating does not cover a 1,500 W space heater at all, yet nothing here vents carbon monoxide into a garage. How often gasoline generators kill indoors — and how the official count keeps being revised — is documented in our CPSC revision matrix, while our refrigerator hub ranks every unit we have verified on the same twelve hours.
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 RIVER 3: manufacturer product page, checked 2026-08-23.
Every quoted number comes from the maker’s page with its source sentence recorded. Every calculated number is marked as such and uses the formula above. Method: How we verify. More: Comparisons.