Model comparison
Two 3 kWh units bought for home backup: EcoFlow's DELTA 3 Ultra against Bluetti's Elite 300, close on capacity and far apart on weight and solar input. EcoFlow DELTA 3 Ultra is the cheaper energy by 9% per watt-hour. BLUETTI Elite 300 answers with weight, max solar input; buy it for those, and the DELTA 3 Ultra for the money.
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EcoFlow3.9/5 overall
Score from the maker's figures and 3 independent reviews
Why it’s here
Buy it if you want the most stored energy per dollar ($0.46 against $0.50 per Wh).
$1,399 · $0.46/Wh
BLUETTI3.5/5 overall
Score from the maker's figures and 3 independent reviews
Why it’s here
Buy it if you carry it more than you run it (58 lb against 72.1 lb).
$1,499 · $0.50/Wh
Compare the differences that matter for your devices; EcoFlow DELTA 3 Ultra leads on 7, BLUETTI Elite 300 on 2, and the rest are equal or not comparable.
| Field | DELTA 3 Ultra | Elite 300 |
|---|---|---|
| Capacity | 3,072 Wh | 3,014 Wh |
| Output (surge) | 3,600 W (7,200 surge) | 2,400 W (4,800 surge) |
| Weight | 72.1 lb | 58 lb |
| Price | $1,399 | $1,499 |
| Price per Wh | $0.46 | $0.50 |
| Chemistry | LiFePO4 | LiFePO4 |
| Rated cycles | – | 6,000 to 80% |
| Max solar input | 800 W | 1,200 W |
| Max AC input | 1,800 W | 1,800 W |
| Wall recharge | 1.5 h to 80% | 2 h |
| Expandable | yes, to 11,000 Wh | no |
| UPS switchover | 10 ms | 10 ms |
| AC outlets | 5 | 5 |
| USB-C ports | 3 | 2 |
| Warranty | 5 years | 5 years |
| Dimensions | 24.6 x 12.9 x 15.6 in | 14.41 x 12.01 x 11.71 in |
Check whether each unit has enough battery and output for the devices you want to run.
| Job | Needs | DELTA 3 Ultra | Elite 300 |
|---|---|---|---|
| a day of home backup (a full-size refrigerator, a router, phones and lights for a day) | 2,323 Wh, 1,351 W start | yes | yes |
| a night of CPAP (a CPAP with its humidifier for one 8-hour night) | 627 Wh, 124 W start | yes | yes |
| two nights of camping (a compressor cooler, lights, phones, a laptop and a fan for two nights) | 2,066 Wh, 157 W start | yes | yes |
| a day in an RV (a 12 V fridge, lights, TV, coffee maker, phones and a laptop for a day) | 648 Wh, 156 W start | yes | yes |
| a working day in a van (a working day of laptop, Starlink, fridge, lights and a fan) | 2,295 Wh, 244 W start | yes | yes |
| a laptop and two phones (a laptop for six hours and two phone charges) | 396 Wh, 60 W start | yes | yes |
Hours = capacity × 0.85 ÷ device watts, with the draws from the device table; "start" is whether the inverter's surge clears the device.
| Device | Draw W | DELTA 3 Ultra h | Start | Elite 300 h | Start |
|---|---|---|---|---|---|
| CPAP machine (with heated humidifier) (with humidifier) | 53 | 49.3 | yes | 48.3 | yes |
| Refrigerator (full-size, ENERGY STAR, ~18 cu ft top freezer) (average draw) | 41 | 63.2 | yes | 62 | yes |
| Laptop (MacBook Air, charging) | 40 | 65.3 | yes | 64.1 | yes |
| Wi-Fi router | 24 | 108.8 | yes | 106.8 | yes |
| Starlink Standard kit (dish + router) | 88 | 29.8 | yes | 29.3 | yes |
| TV, 50-inch LED / Crystal UHD | 89 | 29.3 | yes | 28.8 | yes |
| Space heater, 1500 W | 1,500 | 1.7 | yes | 1.7 | yes |
Both brands' full ranges: EcoFlow and BLUETTI. Every unit at this size: the full table. Your own devices: the sizing calculator.
The one whose surge clears your refrigerator's compressor and whose capacity covers the days you need; both are in the tables above. Between the two, Elite 300 refills faster from a panel, and DELTA 3 Ultra states a UPS switchover time for sitting between the wall and the fridge.
DELTA 3 Ultra at $0.46 per Wh against $0.50. Cycle life changes the lifetime figure: a unit rated for more cycles delivers more energy over its life for the same price.
A small window unit draws 500 to 1,000 W running and several times that for an instant at start; check the surge figure in the table against the air conditioner's label. Either way an afternoon of it empties a 1 kWh unit; the RV page works the rooftop version.
