Head-to-head test
EcoFlow DELTA 3 Ultra vs BLUETTI Apex 300 + 2×B300K
Within a cent of each other per watt-hour, neither of these is the better deal, so the only questions left are how much you actually draw in a day and whether the box ever has to leave the room.
Full profiles: EcoFlow DELTA 3 Ultra → · BLUETTI Apex 300 + 2×B300K →
Written by Gunner GustafsonUpdated
Whole-Home Backup Tester, Station Arena Test Desk
$1,399.00 · direct from EcoFlow
Last checked 7 hours ago. Prices move — check before you buy.
$3,699.00 · direct from BLUETTI
Last checked 7 hours ago. Prices move — check before you buy.
Spec deltas
Forty-six cents a watt-hour against forty-five. That is what separates a $1,399 DELTA 3 Ultra from a $3,699 Apex 300 + 2×B300K once you divide the price by the battery, which means nobody here is overpaying and nobody is getting a bargain. BLUETTI is charging 2.6 times as much for 2.7 times the capacity. The only live question on this page is how much capacity you need.
Answer that honestly and the rest mostly resolves itself. Across the six loads we model, the DELTA covers five with room left over, finishing an eight-hour outage at 63% and a remote workday at 35%. The one it cannot do is full-time van life, where a 4,685Wh day runs it 2,074Wh dry. If your heaviest day looks like a blackout, a workday or a weekend at a campsite, you are shopping above your load.
The other half of the decision is furniture. The DELTA is 72.1 lb in one box, a two-hands, bent-knees lift into a trunk, and then it is done. The Apex arrives as three boxes totalling 213.9 lb, which our record flags as stationary rather than portable. That is not a heavier version of the same product. It is a fixture you site and wire, and it is why three of the six rows here go to the DELTA without capacity ever entering the conversation.
What the Numbers Reveal
Each conclusion stated first — the numbers behind it on one line, the full analysis below.
Typical price
So the extra money buys headroom, and headroom is worth exactly what you use of it. Five of the six loads fit inside the DELTA's 2,611Wh of usable energy, most with slack: 966Wh left after the eight-hour outage, 1,701Wh after the remote workday, 511Wh after the camping weekend. Only the 4,685Wh van-life day breaks it, and it breaks it badly, 2,074Wh short. This is not a spread of small advantages to weigh against each other. It is one yes-or-no question about your own daily draw.
DELTA 3 Ultra: $1,399 for 3,072Wh, $.46 per WhApex 300 + 2×B300K: $3,699 for 8,294Wh, $.45 per WhOf the six modelled loads, only Van Life Daily at 4,685Wh exceeds the DELTA's 2,611Wh of usable energy
Why it mattersAdd up your real worst day before comparing anything else. Under 2,611Wh, the DELTA does the job and you keep $2,300.
solar input
That parity is the whole off-grid argument for spending $3,699, and it is precisely the figure the field reports dispute. At the 1,200W owners describe, the same 8,294Wh needs about seven hours instead of three and a half, which is no longer a morning, it is the entire usable day. Worse for this exact configuration: with two B300K batteries attached, owners report the packs charging at different rates and finishing at different states of chargeB1, plus a firmware fault where the unit does not see solar at all until the cables are unplugged and repluggedB9.
The Apex 300 + 2×B300K accepts 2,400W of solar input; the DELTA 3 Ultra accepts 800W8,294Wh at 2,400W is about three and a half hours from empty; 3,072Wh at 800W is about fourOne owner says BLUETTI could not produce video of an Apex 300 charging above 1,200W, and support told another owner that the cap is normalB2B3The 60V solar input ceiling is the loudest complaint among solar-focused ownersB8
Why it mattersIf solar is your primary refill, verify the Apex's real input before you buy, because it is the one spec that justifies the price and the one owners say they cannot reach.
So the Apex takes the one row that needs DC and then hands the wiring back to you. Reviewers and owners both point at the $300 Hub D1 add-on as how DC and USB come back, and call the unbundling the unit's most-resented costB10B17. The DELTA already has the socket, along with 140W of USB-C for a laptop against the Apex's 100W. Running the other way, the Apex carries two outlets the DELTA's record shows it lacks entirely, 240V and a 30A RV hookup, and one owner charges a plug-in hybrid at 3.3kW off the 240VB5.
The Apex 300's port record lists zero 12V car outlets and USB-C at 100WThe DELTA 3 Ultra's port record lists one 12V car outlet and USB-C at 140WVan Life Daily is the single load the DELTA cannot cover, 2,074Wh short, and the Apex covers it with 2,365Wh spare
Why it mattersVan and RV builders should price the hub into the comparison from the start. If your DC list is a fridge and a fan, the DELTA has the port already.
weight
And the 142 lb is paid once rather than every trip, which is the part that actually matters. Get the Apex into position and its mass stops existing while its capacity keeps working. That makes these two different categories rather than two sizes of the same thing: one is a box you put in a car, the other is a fixture you site and wire, which is also why our record flags it stationary.
72.1 lb in one box against 213.9 lb spread across three, a 142 lb differenceWeekend Camping, Tailgate Party and CPAP Overnight all go to the DELTA while the Apex holds 7,050Wh usable, enough to cover each of them several times overA reviewer calls the base Apex unit alone too big and heavy for most people to carry on their ownB12
Why it mattersIf the unit will sit in one place for years, ignore the weight and let capacity decide. If it moves more than twice a year, the DELTA has won before you read another spec.
The specific dimensions that decide these two units — everything else is a tie.
Your Life, Your Pick
Selected because: Five of the six loads we model fit inside the DELTA 3 Ultra's 2,611Wh of usable energy; the sixth, a 4,685Wh van-life day, is the entire case for the Apex.
Look at how the three Apex wins are actually won. The eight-hour outage and the remote workday are not jobs the DELTA fails; it ends the outage at 63% with 966Wh still in the pack and the workday at 35% with 1,701Wh. What the Apex adds on those rows is a second and a third night, 5,405Wh left over and about 3.3 more evenings like the first. That is genuinely valuable if your outages run long, and completely uncollected if they do not.
The row that is not about headroom is van life, and it is decisive. A 4,685Wh day against 2,611Wh usable leaves the DELTA 2,074Wh short, which the engine scores as 56% of the day covered. No amount of careful rationing closes that. If you are wiring a van you are not choosing between these two, you are buying the Apex and budgeting for the ports it does not have.
Portability & Form Factor
Selected because: 72.1 lb in one box against 213.9 lb across three settles three of the six rows before capacity is consulted.
weight
Seventy-two pounds is a suitcase you would be annoyed to check: two hands, bent knees, one person, done. Two hundred fourteen pounds arrives as three separate boxes, which beats one impossible lift and is still nothing you reposition on a whim. The honest way to read that 142 lb difference is as a one-time cost. You pay it once, getting the Apex to where it lives, and then never again.
Which is why the Apex loses the campsite, the tailgate and the nightstand while holding 7,050Wh of usable energy, several times what any of those three asks for. It is not outgunned on those rows. It simply cannot get there.
Lifetime Value
Selected because: The two land within a cent of each other per watt-hour, so the interesting number is what each costs per kilowatt-hour you actually cycle.
cost / lifetime kWh
Eleven cents a lifetime kilowatt-hour against seven. The Apex is the cheaper energy over the rated life of its cells, roughly 49,766 kWh against 12,288, and that is real: 6,000 rated cycles at 8,294Wh is an enormous amount of throughput. But a per-kilowatt-hour figure only pays out on kilowatt-hours you move. If your heaviest night is the 1,645Wh outage, you have bought 8,294Wh of cells and you are cycling a fifth of them, and the seven-cent figure quietly becomes theoretical.
Both cycle counts are minimums rather than expiry dates, and neither pack dies at the limit, it settles to about 80% of the capacity it started with. On a weekend rhythm the DELTA's rated life runs 38.5 years and the Apex's 57.7. Neither is a number you will personally test, which is the clearest sign that cycle life should not be deciding this.
Growth Path
Selected because: The DELTA is sealed at 3,072Wh while the Apex starts at 8,294Wh and grows, which only matters if you cannot predict your own ceiling.
solar input
The DELTA's real weakness lives here, and it is worth saying before anyone else does: what you buy is the ceiling. It is sealed at 3,072Wh with no expansion port, so outgrowing it means buying a second unit, and the resale arithmetic on that is never fun. The Apex starts at 8,294Wh and takes more BLUETTI batteries after that, a path that at this size points toward partial-home backup rather than a bigger camping trip.
The catch is that expandability is insurance against not knowing your own load, and your load is knowable. You can total a day's draw this afternoon. If the number comes in under 2,611Wh, the sealed box is not a compromise, it is the right size, and the Apex's growth path is headroom stacked on headroom you were not using.
Brand Trust
Selected because: At $3,699 for a three-box system, how the maker answers a support ticket stops being a footnote.
Both makers have a support story worth reading before you spend, and they fail differently. EcoFlow runs US phone, email and chat, and experiences split hard: prepaid replacement labels and quick swaps for many, long waits and refurbished units against new claims for others. BLUETTI's pattern is the more worrying one at this price, heavily email-based with China timezone delays, and the field record matches the reputation. One Apex owner spent two weeks troubleshooting and another week waiting on an RMA approval, with no reply 48 hours after asking for an updateB4, and the wider picture is described as ranging from helpful to non-existentB11.
Warranty does not break the tie. Both are five years on paper, and BLUETTI's five is a maximum term rather than a default, conditional on buying direct or registering the unit. Neither brand offers much afterwards: EcoFlow lists no parts or service out of warranty, and BLUETTI has no spare-parts policy for some models. Buy the one whose support you are least likely to need, which on this evidence is the simpler box.
Strengths & trade-offs
EcoFlow DELTA 3 Ultra
Strengths
- +Costs $2,300 less
- +Lighter by 141.8 lb
Trade-offs
- –Sealed capacity — the Apex 300 + 2×B300K can add batteries to grow past 3,072Wh; this one can't.
- –Shorter-lived battery — rated for 4,000 charge cycles vs the Apex 300 + 2×B300K's 6,000, so it wears out sooner.
BLUETTI Apex 300 + 2×B300K
Strengths
- +Larger battery capacity
- +Higher AC output
- +Faster solar charging
- +Rated for 6,000 charge cycles — much longer battery lifespan
Trade-offs
- –Substantially more expensive (+$2,300) than the DELTA 3 Ultra.
- –Significantly heavier (+141.8 lbs), making it harder to move.
- –Very heavy unit that may be difficult for one person to lift.
Will It Power Your Gear?
Scenario math and per-appliance runtimes, modeled from the spec record.
Scenario verdicts
We ran the math on six real-world scenarios. Here's which unit survives your actual life.
SCN-01 · 2 nights · needs 2,100Wh
Weekend Camping
Two nights off-grid with essential comfort
DELTA 3 Ultra
Both cover the 2,100Wh weekend, so this row gets decided in the driveway. The DELTA 3 Ultra goes in the car at 72.1 lb and comes home with 511Wh in hand. The Apex holds 7,050Wh usable against a 2,100Wh weekend and still is not coming with you.
Battery budget usedlower = more headroom
LOAD Phone Charger 15W×6h · LED Lights 40W×8h · Box Fan 75W×14h · CPAP Machine 40W×16h
SCN-02 · 8 hours · needs 1,645Wh
8-Hour Blackout
Keep the essentials running through a night without power
Apex 300 + 2×B300K
The Apex takes this one on second nights, not on the first. Both ride out the 1,645Wh evening: the DELTA ends at 63% with 966Wh, a bit over half of another night, while the Apex ends at 23% with 5,405Wh, about 3.3 more nights like it. If your outages have a habit of ending by bedtime, that advantage never gets collected.
Battery budget usedlower = more headroom
LOAD Fridge 150W×8h · Router + Modem 20W×8h · LED Lights (4 bulbs) 40W×6h · Phone Charger 15W×3h
SCN-03 · 8 hours · needs 320Wh
CPAP Overnight
Sleep therapy without interruption — the #1 medical use case
DELTA 3 Ultra
A CPAP night is 320Wh, roughly 12% of the DELTA 3 Ultra's usable energy and 5% of the Apex's, so capacity is a formality, and the two published noise ratings come from different makers measuring their own way and will not settle it either. What decides it is which box can be next to the bed. The DELTA is one 72.1 lb unit a person can carry to a nightstand, and it has a 12V socket, so a CPAP with a DC cord can skip the inverter entirely. The Apex is a three-box, 213.9 lb installation whose record lists no 12V outlet at all.
Battery budget usedlower = more headroom
LOAD CPAP Machine 40W×8h
SCN-04 · 8 hours · needs 910Wh
Remote Workday
Full work day off-grid without power anxiety
Apex 300 + 2×B300K
The Apex 300 + 2×B300K clears the workday at 13% used, banking 6,140Wh — late work, extra calls, or a second laptop charge without arithmetic. The DELTA 3 Ultra at 35% also finishes, with 1,701Wh of slack for the unplanned.
Battery budget usedlower = more headroom
LOAD Laptop 60W×8h · External Monitor 30W×8h · Router + Modem 20W×8h · Phone Charger 15W×2h
SCN-05 · 4 hours · needs 670Wh
Tailgate Party
Game day power for the crew
DELTA 3 Ultra
The 400W startup surge is the only real load here and both shrug at it, with 7,200W and 7,680W of surge on tap. So it comes down to the lift over the tailgate: one 72.1 lb box, or three boxes totalling 213.9 lb. The DELTA covers the 670Wh with 1,941Wh left and gets there in a single hand-off.
Battery budget usedlower = more headroom
LOAD Blender 400W×0.5h · LED TV (55") 80W×4h · Bluetooth Speaker 15W×4h · Phone Charger (×3) 45W×2h
SCN-06 · 24 hours · needs 4,685Wh
Van Life Daily
A full day of mobile living — the ultimate endurance test
Apex 300 + 2×B300K
This is the row that justifies the Apex. A 4,685Wh day is past what the DELTA 3 Ultra can do at all: 2,611Wh usable leaves it 2,074Wh short, 56% of the day covered. The Apex finishes at 66% used with 2,365Wh spare. Plan the 12V side deliberately, though, because its port record lists zero 12V car outlets and a van's fridge, fan and water pump are all DC natives.
Battery budget usedlower = more headroom
LOAD Mini-Fridge 150W×24h · Laptop 60W×4h · Phone Charger 15W×3h · LED Lights 40W×5h · Fan 75W×8h
The Load Test
RUNTIME = (Wh × 0.85) ÷ LOAD
None of the scenarios above exactly yours? Build it. Toggle what you'd plug in; both units are tested against the combined draw.
Essentials
Comfort & Convenience
High-Draw Appliances
Test duration
8h
Continuous draw
205W
Projected runtime
For this load: Apex 300 + 2×B300K runs 34.4h vs 12.7h.
$3,699 list · direct from BLUETTI
Modeled from the spec record — same math as the tables below. Methodology
Runtime by appliance
Real-world runtime estimates for common appliances, modeled at 85% inverter efficiency.¹
Essentials
The basics you need runningscale 0–470hComfort & Convenience
Makes off-grid life actually enjoyablescale 0–94hHigh-Draw Appliances
These reveal the real limitsscale 0–7.1h¹ Runtime = (capacity × 0.85) ÷ appliance watts. Within each group, all bars share one time scale (the group's longest runtime), so lengths are comparable across appliances; identical runtimes collapse into a single blue/orange bar. Actual runtime varies with battery age, temperature, and simultaneous loads — see methodology.
Conclusion
September 13, 2026
Verdict: the EcoFlow DELTA 3 Ultra
Buy the DELTA 3 Ultra. At $1,399 against $3,699 you are paying within a cent per watt-hour either way, so the $2,300 gap buys quantity of battery rather than quality of engineering, and of the six loads we model only one, a 4,685Wh van-life day, actually exceeds the DELTA's 2,611Wh of usable energy. The Apex 300 + 2×B300K takes the blackout and workday rows on headroom rather than capability: the DELTA finishes an eight-hour outage at 63% with 966Wh still in the pack. Where the Apex genuinely pulls ahead is the stuff you can name in advance, namely a day over 2,611Wh, a 240V load, a 30A RV hookup, or a system that gets sited once and wired in. If none of those is on your list, the smaller box does the same jobs and leaves $2,300 for panels.
Editor-assigned confidence, based on cited owner research and spec analysis.
List prices as of September 13, 2026. The links below open EcoFlow's and BLUETTI's current prices.
$1,399.00 · direct from EcoFlow
Last checked 7 hours ago. Prices move — check before you buy.
or check the Apex 300 + 2×B300K price$3,699.00 list
Written by Gunner Gustafson, Whole-Home Backup Tester · Station Arena Test Desk · Updated September 13, 2026
Measured Data
Benchmark scores and the full spec record, side by side.
Benchmark scores
Not rated for both units (minimum threshold unmet): UPS, RV Living, Solar Generator, Tailgating.
Full specifications
ᵈ Derived: price ÷ rated capacity. See the data behind our comparisons →
Comparison ToolAdd more power stations, side by sideOpen Tool →How these numbers are produced
Numeric verification
Every figure on this page traces to our spec database or arithmetic on it — no estimated numbers.
Owner claims
Statements about owner experience are cited to published reviews — see Sources & Research Notes below.
Runtime model
Runtime = (rated capacity × 0.85 inverter efficiency) ÷ device wattage. Solar recharge estimates assume panels deliver 70% of rated output. Cold weather, battery age, and stacked loads reduce real-world results.
Power Score
Computed from 14 published spec dimensions, weighted per use-case bench. Higher is better; a unit must meet a bench's minimum threshold to be rated.
See the full weight table and data sourcing on our methodology page →Class ranking (the star rating)
Each unit's star score is a category ranking, not customer reviews — no buyer opinions feed it. We score every station on size-independent quality (value, output, portability, endurance, ports, warranty, and more), then percentile-rank it against the other units in its capacity class, so a class-leading compact unit and a class-leading whole-home unit can both earn 5★. Here, DELTA 3 Ultra rates 4.7/5 (80th percentile of 26 Large-class units), and Apex 300 + 2×B300K rates 3.4/5 (7th percentile of 29 Whole-Home / Off-Grid-class units).
How the class ranking is computed →Test Notes & Caveats
Hidden gotchas and advantages we spotted that you won't find on the product page.
Weight: paid once, then irrelevant
142 lb separates these two and you pay it once. Getting the Apex's three boxes into position is the whole of the difficulty; after that it sits there working and its mass stops being your problem. The DELTA's 72.1 lb is the opposite arrangement, a cost you pay on every single trip, which is fine because it is one person's lift. Decide by how often the unit moves, not by how heavy it is.
Apex 300 + 2×B300K: 45dB Published
45dB is about as loud as a running refrigerator. The DELTA 3 Ultra is rated 30dB — lower, but published by a different maker measuring its own way, so the two figures are not a like-for-like gap. For most people, fan noise around 45dB and up is where sleep starts to suffer.
The DELTA 3 Ultra's ceiling is the price of admission
Our pick holds the weaker hand here and it is worth naming plainly. The DELTA 3 Ultra is sealed at 3,072Wh with no expansion port, so growing past it means buying a second unit. The Apex 300 + 2×B300K starts at 8,294Wh and takes more batteries after that, which at this size points at partial-home backup rather than a longer camping trip. The only defence is that a day's draw is something you can measure this afternoon. Expandability is insurance against not having done that.
Warranty: No Difference
Both units carry the same 5-year warranty, so coverage isn't a tiebreaker here. The Apex 300 + 2×B300K's figure is a maximum rather than a guarantee — it depends on buying direct from BLUETTI or registering the unit, since reseller purchases carry a shorter term. Worth saying because the per-dollar framing can suggest otherwise: the DELTA 3 Ultra works out at 3.6 years of cover per $1,000 spent against the Apex 300 + 2×B300K's 1.4, but that spread is the price gap, not the terms.
Count the kilowatt-hours, not the cycles
6,000 rated cycles against 4,000 flatters the Apex twice over, because its cycle is 8,294Wh and the DELTA's is 3,072Wh. The honest figure is lifetime energy: roughly 49,766 kWh against 12,288 kWh. Both counts are minimums, and neither pack dies at the limit, it settles to about 80% of original capacity. Also worth noticing that 38.5 years of weekend use is already a longer rated life than anyone's interest in a power station.
Full record above — the Test Desk pick is the DELTA 3 Ultra.
Check DELTA 3 Ultra price →or check the Apex 300 + 2×B300K priceOwnership Analysis
What happens after you buy — true cost of ownership, brand trust, and growth potential.
Lifetime value
Service lifeyears at one full cycle per day
Lifetime energy delivered
Cost per delivered kWh
│ warranty ends · Reaching the cycle rating means ~80% capacity remains — degraded, not dead.
Analyst note
The DELTA 3 Ultra is cheaper to buy, but the Apex 300 + 2×B300K is cheaper to own. At $0.07/kWh over its lifetime vs $0.11/kWh, the Apex 300 + 2×B300K's higher cycle life and capacity make each dollar go further over the years.
Brand trust
EcoFlow
Ecosystem
Largest in portable power — 12-15 models across DELTA Pro, DELTA 3, and RIVER 3 series, plus solar panels and smart home panels
Support
US phone, email and chat, with a reputation that splits down the middle: prepaid return labels and quick swaps for plenty of people, long silences and refurbished units against new claims for plenty of others. Buying through a retailer with its own returns policy is the cheap insurance.
Community
Largest community in the space — Reddit r/Ecoflow_community (~31K members), multiple Facebook groups, and an official community forum
App experience
Rated 4.6/5 iOS (~8,400 ratings) · 4.2/5 Android (~17,000 ratings)
Unique strength
Fastest-charging technology (X-Stream), deepest product ecosystem, and most active innovation cadence. At the very top of the range, the DELTA Pro Ultra platform stacks batteries and inverters into whole-home backup — a flagship path, not a line-wide feature.
Worth knowing
EcoFlow floated a subscription tier for advanced app features in early 2025 and shelved it after the backlash, and it offers no parts or service once the warranty is up. The app itself is well rated on both platforms.
BLUETTI
Ecosystem
One of the broadest lineups — 15-20+ models from budget (AC2A) to flagship portable (Apex 300, 2764.8Wh). Includes specialized products: vehicle solar hubs, sodium-ion cold-weather units, and balcony storage systems.
Support
The most inconsistent support in the category, mostly email with China timezone delays. Some tickets go smoothly; others turn into weeks of troubleshooting, discount offers in place of repairs, and confusing claim paths for third-party purchases. Buying direct from BLUETTI improves the odds, and it is also what preserves the full five-year warranty term.
Community
Active and growing — Reddit r/bluetti has a dedicated community. Second-largest after EcoFlow in engagement.
App experience
Rated 4.5/5 iOS and Android — tied for best app experience in the category. V3.0 UI redesign was well-received.
Unique strength
Among the best capacity-to-price ratios available — several Elite and Apex units are the lowest $/Wh in the catalog. Widest product diversity including industry-firsts like sodium-ion cold-weather units and dual solar+alternator vehicle hubs. LFP across the rest of the range, though rated cycle life spans 2,500 (EB3A) to 6,000, and it varies WITHIN the Elite range rather than tracking it — the Elite 300 and Elite 200 V2 are rated 6,000 while the Elite 30 V2, Elite 10 Mini, Elite 320 and Elite 400 are rated 3,000+ and the Elite 100 V2 4,000+, so check the specific model. Dual-voltage (120V/240V) in flagships.
Worth knowing
BLUETTI's pricing is among the best capacity-per-dollar in the catalogue, which is exactly why this matchup is a sizing question rather than a value one. The flip side is no spare-parts policy on some models, so an older unit can become unrepairable rather than merely expensive to repair.
Analyst note
Both are large, credible brands with support you would rather not test. The difference that matters here is the stake. A $1,399 sealed box that fails is an annoying replacement; a $3,699 three-box system is a support relationship you may actually need. Weight the support column more heavily on the BLUETTI side of this page than you would on a cheaper one.
Growth path
DELTA 3 Ultra
FIXED CAPACITYFixed at 3,072Wh — a sealed, complete system rather than a starting point. There's no expansion port, so that figure is the ceiling: check it against your longest unplugged stretch before you buy.
Accepts up to 800W of solar. Suitable for a 1-2 panel setup.
Generous port selection supports complex multi-device setups.
Apex 300 + 2×B300K
EXPANDABLESupports BLUETTI expansion batteries, so you can add capacity later without replacing the base unit — useful if your needs may climb past 8,294Wh.
Accepts up to 2,400W of solar. Enough for a serious multi-panel array.
Generous port selection supports complex multi-device setups.
Expansion batteries are BLUETTI-specific. You're investing in the BLUETTI ecosystem.
Realistic full solar rechargeat 70% of rated panel output — see methodology
Analyst note
The DELTA 3 Ultra is sealed at 3,072Wh, which is fine if that covers you. The Apex 300 + 2×B300K starts at 8,294Wh and can grow beyond it with BLUETTI expansion batteries — real headroom the DELTA 3 Ultra doesn't have if your needs climb toward partial-home backup.
What Owners Report
Patterns from published owner reports and long-term reviews — every claim cited to its source below.
EcoFlow DELTA 3 Ultra
Start with a caveat we would rather not have to give. Most of the coverage filed under the DELTA 3 Ultra is actually about the Ultra Plus, a different SKU, and our own research note flags 13 of 15 entries that wayA0. Capacity, output, surge and chassis are shared between the two, so character claims carry over; anything touching solar input, expansion or weight does not, and those entries are left out here. Read the rest as review-bench experience rather than long-term ownershipA0.
What is there is consistent and mildly reassuring. Reviewers describe the fans as unobtrusive even with the inverter pushed to maximum outputA1A2, and the UPS behaviour as seamless, with no dips or shutdowns when the unit is pulled off the wallA4A5A6. Build quality draws repeated praise, down to the sliding port coversA9A15. One reviewer ran a 300W to 600W workstation load for a little over four and a half hoursA7, and got through an eight-hour remote workday with 40% leftA8. The recurring gripe is the screen washing out in direct sun, which took a cupped hand to readA11.
“Even when you're pushing it hard, the DELTA 3 Ultra Plus runs much quieter than older EcoFlow models, like the DELTA 2 Max.”
Sources
thesolarlab.com · postperspective.com · appleinsider.com · digitaltrends.com · popsci.com
BLUETTI Apex 300 + 2×B300K
The Apex 300 + 2×B300K's field record is thin and recent by construction: a 2025 launch, nothing beyond about six months of ownership, no owner community specific to this configuration, and no cold-weather reports at allB0. What exists leans on two DIY solar forum threads, a van-conversion thread, an aggregation blog, and professional hands-on reviews, one of which tested an Apex 300 with a B300K attachedB0. Treat the pattern below as early signal rather than settled history.
The signal is not flattering, and it clusters on exactly the uses that justify the price. Owners in this multi-battery setup report the packs charging at different rates and finishing at different states of charge, with support calling that normal and one owner concluding it makes the system a bad choice off-gridB1B3. Another asked BLUETTI for video of an Apex charging above 1,200W and says none arrivedB2. The 60V solar input ceiling is the loudest complaint in the solar crowdB8, alongside a firmware fault where the unit does not register solar until you unplug and replug the cablesB9. Support itself reads as a coin flip, from helpful to non-existentB11, with one multi-week RMA saga on recordB4.
On the credit side, the hardware reviews well. Fan noise is described as even and rattle-free enough to sit near a sleeping areaB14, the 20W AC idle draw is called efficient for long outagesB15, though 20W of standby across an eight-hour night is another 160Wh on top of the 320Wh a CPAP itself wants. One reviewer found he could run essentials for more than a full day without rationingB16. A van builder priced the whole system against a DIY build of comparable capacity and came out level or betterB6, and another owner charges a plug-in hybrid at 3.3kW off the 240V outputB5. The weight is acknowledged as more than one person should carryB12.
“For me the 240V output is great. I can stick it in the back of my PHEV and use the 240V output to charge at 3.3KW when I stop.”
Sources & Research Notes
Every owner claim in this report is traceable to a published source. The bracketed references above resolve here.
Recurring owner themes
- Reviewers consistently praise the quiet fan operation of the Ultra-tier unit compared to older EcoFlow models, though this is described in professional test conditions rather than long-term ownership. [DELTA 3 Ultra · 2 entries]
- UPS/switchover performance is repeatedly called seamless with no observed dips or shutdowns during power interruption tests. [DELTA 3 Ultra · 3 entries]
- The unit's substantial 74 lb weight is flagged across multiple reviews as a portability drawback, mitigated somewhat by wheels and handle design. [DELTA 3 Ultra · 2 entries]
- Build quality/durability (casing, cable, port covers) is repeatedly highlighted as premium and well-engineered. [DELTA 3 Ultra · 2 entries]
- When multiple Apex 300 units (as in this 2x-B300K configuration) are charged together, owners report state-of-charge sync problems and solar input capped far below the advertised rating, which Bluetti support has called 'normal' behavior. [Apex 300 + 2×B300K · 3 entries]
- Customer/RMA support experience is inconsistent — some owners report smooth help, others describe multi-week delays and unresponsive tickets. [Apex 300 + 2×B300K · 2 entries]
- The base unit's 60V solar input ceiling and a firmware bug that drops solar detection (requiring an unplug/replug) are the two most-cited technical gripes among solar-focused owners. [Apex 300 + 2×B300K · 2 entries]
- Because the Apex 300 ships with no built-in DC/USB ports, owners and reviewers alike flag the mandatory ~$300 Hub D1 accessory as an unexpected added cost. [Apex 300 + 2×B300K · 2 entries]
- Despite being marketed as 'portable,' the unit's weight (~38kg/85lb base alone, more with B300K batteries) leads multiple sources to describe it as effectively a stationary/semi-permanent installation rather than something carried around. [Apex 300 + 2×B300K · 2 entries]
- A1
“Even when you're pushing it hard, the DELTA 3 Ultra Plus runs much quieter than older EcoFlow models, like the DELTA 2 Max.”
thesolarlab.com — EcoFlow DELTA 3 Ultra Plus Review: The Ultimate DELTA? · 2025-09/10 (approx) · [positive]
- A2
“Even when you're pushing the inverter to its maximum output, the fans never become annoying or distracting.”
thesolarlab.com — EcoFlow DELTA 3 Ultra Plus Review: The Ultimate DELTA? · 2025-09/10 (approx) · [positive]
- A4
“Many power stations limit you to the input wattage when outputting power, but this EcoFlow power station does not.”
thesolarlab.com — EcoFlow DELTA 3 Ultra Plus Review: The Ultimate DELTA? · 2025-09/10 (approx) · [positive]
- A5
“Over my career I have become accustomed to APC batteries immediately switching on when there is a power hit or power shut-off, and the EcoFlow Delta 3 Ultra Plus works in the exact same way.”
postperspective.com — Review: EcoFlow Delta 3 Ultra Plus Portable Power Station · 2026-04 · [positive]
- A6
“I didn't experience any shut-offs or dips when I unplugged the EcoFlow from the wall.”
postperspective.com — Review: EcoFlow Delta 3 Ultra Plus Portable Power Station · 2026-04 · [positive]
- A7
“Using Maxon's Cinebench 2026 GPU benchmark, I was pulling between 300W and 600W on one of the AC outputs... the EcoFlow Delta 3 Ultra Plus would last a little over 4.5 hours.”
postperspective.com — Review: EcoFlow Delta 3 Ultra Plus Portable Power Station · 2026-04 · [positive]
- A8
“I was able to work remotely for an eight-hour day with 40% power left, which included running my laptop, desktop workstation and monitors.”
postperspective.com — Review: EcoFlow Delta 3 Ultra Plus Portable Power Station · 2026-04 · [positive]
- A9
“It does not feel cheap or fragile. Everything from the outer shell case to the plastic buttons and the AC cable feels substantial and durable enough to withstand day-to-day wear and tear.”
appleinsider.com — EcoFlow Delta 3 Ultra Plus review: Premium, but solid power · 2025-11-16 · [positive]
- A11
“But, while facing the sun, I had to employ the classic "cup hands cover" maneuver to get a clear look at the screen status.”
appleinsider.com — EcoFlow Delta 3 Ultra Plus review: Premium, but solid power · 2025-11-16 · [negative]
- A15
“I really love how the rear panel doors for the input ports slide into protective slots when in use.”
popsci.com — EcoFlow DELTA 3 portable power station series first impressions · 2025-09-29 · [positive]
- B1
“When the units are charging from the grid they charge at different rates and not together... you may have one at 100% and one at 50%.”
DIY Solar Power Forum — thread 'Bluetti Apex 300 problems' · 2025-09 · [negative]
- B2
“I have requested a short video from Bluetti showing an APEX 300 actually charging more than 1200 watts. They have been unable to produce one.”
DIY Solar Power Forum — thread 'Bluetti Apex 300 problems' · 2025-09 · [negative]
- B3
“Bluetti support says this is normal... This makes them a bad choice for off grid applications.”
DIY Solar Power Forum — thread 'Bluetti Apex 300 problems' · 2025-09 · [negative]
- B4
“It has taken me 2 weeks of troubleshooting with them and a week to get an RMA approval... I have asked for updates with NO response 48 hours later.”
DIY Solar Power Forum — thread 'Apex 300 Support issues' · 2025-11 · [negative]
- B5
“For me the 240V output is great. I can stick it in the back of my PHEV and use the 240V output to charge at 3.3KW when I stop.”
DIY Solar Power Forum — thread 'Bluetti Apex 300 launched today… anyone have thoughts?' (page 2) · 2025-05 · [positive]
- B6
“It came in just shy of £1500... Pricing up a similar system from scratch with similar capacity, solar charger, split charger, smart shunt, inverter ect was all coming in at a similar if not slightly higher price.”
VW T6 Transporter Forum — thread 'Bluetti Apex 300' · 2025-07 · [positive]
- B8
“The 60V solar limit is the most common and vociferous complaint, with users calling it "misleading" and a "joke".”
BIKMAN TECH blog aggregating user/forum reports — 'Bluetti APEX 300 - Everything You Need to Know' · 2025-11 · [negative]
- B9
“the unit failing to detect solar input until the cables are physically unplugged and replugged. Bluetti support has reportedly acknowledged this as a known firmware issue”
BIKMAN TECH blog aggregating user/forum reports — 'Bluetti APEX 300 - Everything You Need to Know' · 2025-11 · [negative]
- B10
“widespread frustration over the "unbundling" strategy and the "hidden cost" of the Hub D1 for "missing" DC/USB ports.”
BIKMAN TECH blog aggregating user/forum reports — 'Bluetti APEX 300 - Everything You Need to Know' · 2025-11 · [negative]
- B11
“Customer support is dangerously polarized. User experiences range from "great" and "helpful" to "notoriously non-existent" and "a disaster".”
BIKMAN TECH blog aggregating user/forum reports — 'Bluetti APEX 300 - Everything You Need to Know' · 2025-11 · [mixed]
- B12
“it weighs in at 38kg, and is probably much too big and heavy for most people to carry alone.”
Trusted Reviews — 'Bluetti Apex 300 Review' · 2025-10 · [mixed]
- B14
“Fan noise remains even, with no distracting pitch or rattle. This makes the Apex 300 usable near sleeping areas or indoor workspaces without disturbance.”
Yanko Design — 'BLUETTI Apex 300 Review: The All-in-One Solar, Gas, and Battery Solution' · 2025-05 · [positive]
- B15
“Efficient 20W AC idle drain extends runtime significantly during extended outages.”
Yanko Design — 'BLUETTI Apex 300 Review: The All-in-One Solar, Gas, and Battery Solution' · 2025-05 · [positive]
- B16
“With some portable power stations, I'd have to ration power more carefully, but with this system, I could run essentials for more than a full day if I needed to.”
Techspective — 'Bluetti Apex 300 with B300K Review' · 2025-09 · [positive]
- B17
“Not having DC or USB ports on the face is a tradeoff. The Hub D1 solves the problem—but it's an additional $300 accessory that you then have to bolt on after the fact.”
Techspective — 'Bluetti Apex 300 with B300K Review' · 2025-09 · [mixed]
Research compiled September 13, 2026.
Who Should Buy Which
Buy the DELTA 3 Ultra if you…
- →You are prepping for outages that end the same night. A 1,645Wh evening leaves the DELTA at 63% with 966Wh in reserve, and you spent $1,399 rather than $3,699 to get there.
- →The unit has to travel. Campsites, tailgates, a friend's house after a storm: one box at 72.1 lb, six AC outlets, a 12V car socket, and 140W of USB-C for the laptop.
- →You want it beside the bed. A CPAP night is 320Wh, about 12% of the DELTA's usable energy, and this is a box one person can carry into a bedroom rather than one that lives where it was installed.
- →You work off it. A reviewer got an eight-hour remote day out of the same hardware with 40% leftA8, and the modelled workday still leaves 1,701Wh of slack.
Buy the Apex 300 + 2×B300K if you…
- →You are wiring a van or a small cabin and your day is genuinely 4,685Wh. The DELTA is 2,074Wh short of that and the Apex finishes with 2,365Wh spare. Budget the DC hub as part of the purchase price, not as an afterthought.
- →You need 240V or a 30A RV hookup. The DELTA's port record shows neither; the Apex has one of each.
- →Your outages run past one evening. 5,405Wh left after an eight-hour night is about 3.3 more nights like it.
- →The system gets sited once and never moved, and you are willing to verify its real solar input yourself before the return window closes.
If neither fits
If your worst case is a phone, a laptop and a fridge through a summer evening, both of these are several times the unit you need, and a far smaller portable from the entry tier will do it for a fraction of $1,399. And if what you actually want is the house backing itself up through a transfer switch, neither of these is that either: look at a hardwired battery and inverter system instead of stacking portables toward one.
The Bottom Line
The verdict rests on one number that is not a spec: the size of your own worst day. At effectively the same price per watt-hour, BLUETTI is not asking for a premium, it is asking whether you need 8,294Wh, and five of the six loads here say no. Under 2,611Wh of usable energy the DELTA 3 Ultra does the same jobs, in one box a person can carry, for $2,300 less.
Over it, do not hesitate. The van-life day, a 240V load, a 30A hookup, or outages that run past one evening all point at the Apex, and it earns them. Just go in knowing you are buying a fixture rather than a portable, pricing the DC hub as part of the purchase, and checking the real solar input yourself before the return window shuts. Everyone else should buy the smaller box and put the difference into panels.
Frequently Asked Questions
Answers drawn from the spec record and cited owner research.
Is the BLUETTI Apex 300 + 2×B300K worth $2,300 more than the EcoFlow DELTA 3 Ultra?
Only if you will use the extra battery. Per watt-hour the two are within a cent of each other, $.46 against $.45, so you are buying quantity rather than quality. Of the six loads we model, only a 4,685Wh van-life day exceeds the DELTA's 2,611Wh of usable energy, and the other five fit, most of them comfortably.
Can the EcoFlow DELTA 3 Ultra run a van full time?
No. Full-time van life in our model draws 4,685Wh a day, and the DELTA has 2,611Wh usable after the flat 85% derate we apply to every unit, leaving it 2,074Wh short, or 56% of the day covered. It is the one load on this page it cannot finish, and it is not close. The Apex 300 + 2×B300K covers the same day with 2,365Wh spare.
Does the BLUETTI Apex 300 have 12V and USB ports?
Its record lists two USB-A and two USB-C at 100W, and zero 12V car outlets, which in our port data is an affirmative none rather than a missing field. Reviewers and owners point to the $300 Hub D1 accessory as the way DC comes back, and call that unbundling the unit's most-resented cost. The DELTA 3 Ultra has a 12V car socket on the box and 140W of USB-C.
Which one charges faster from solar?
The Apex, narrowly, which is the surprise. 8,294Wh at its rated 2,400W input is about three and a half hours from empty against roughly four for the DELTA's 3,072Wh at 800W, so the bigger system does not cost you a longer solar day. The caveat is that owners dispute the rated input, describing a real-world cap nearer 1,200W that support calls normal, plus a firmware fault that stops solar being detected until the cables are reseated. At 1,200W that refill takes about seven hours.
Can either of these run a 240V appliance or an RV 30A hookup?
Only the BLUETTI. Its record shows one 240V outlet and one 30A RV outlet, and the DELTA 3 Ultra's shows neither. One owner uses the 240V to charge a plug-in hybrid at 3.3kW. If a well pump, a 240V dryer or an RV shore cord is on your list, that single row settles the page no matter how the capacity math falls.
Brand matchup
EcoFlow vs BLUETTI: measured across every matchup →Where to buy
EcoFlow DELTA 3 UltraPick
$1,399.00
$1,399.00 · direct from EcoFlow
Last checked 7 hours ago. Prices move — check before you buy.
BLUETTI Apex 300 + 2×B300K
$3,699.00
$3,699.00 · direct from BLUETTI
Last checked 7 hours ago. Prices move — check before you buy.
Prices may vary by retailer and are subject to change.