Head-to-head test
EcoFlow DELTA Pro 3 vs BLUETTI Apex 300 + B500K
The Apex pair costs more and holds nearly twice the energy, so the DELTA Pro 3 wins only for buyers whose longest outage already fits inside 4,096Wh.
Full profiles: EcoFlow DELTA Pro 3 → · BLUETTI Apex 300 + B500K →
Written by Gunner GustafsonUpdated
Whole-Home Backup Tester, Station Arena Test Desk
Spec deltas
The Apex 300 + B500K costs $500 more than the DELTA Pro 3 and holds 3,789Wh more: 7,885Wh against 4,096Wh, nearly a second DELTA Pro 3's worth of battery. Both are stationary home-backup units, so that extra money buys the one thing a home-backup unit exists for, which is more nights before the lights go out.
Run our 8-hour blackout profile, 1,645Wh of fridge, lights and devices, and both finish the night easily. The difference is what's left: enough for 1.1 more nights on the DELTA Pro 3 and 3.1 more on the Apex. The Apex is also rated for 6,000 cycles to 4,000, and runs resistive loads up to 7,680W in Power Lifting mode.
The DELTA Pro 3 has real answers of its own. It's the cheaper unit, it's one 112.4 lb box rather than 183 lbs split across two, and its USB and 12V outputs are on the box, while every USB and 12V port on the Apex needs the separately sold Hub D1B12. If 4,096Wh outlasts your longest outage, those are reasons to take it and keep the difference.
What the Numbers Reveal
Each conclusion stated first — the numbers behind it on one line, the full analysis below.
The first night of an outage is the easy one; both units clear it at under half their capacity. A home-backup buyer is paying for the nights after that, and that is where the DELTA Pro 3 runs dry about two nights before the Apex does.
Apex 300 + B500K: 7,885Wh, 6,702Wh usableDELTA Pro 3: 4,096Wh, 3,482Wh usable8-Hour Blackout profile draws 1,645Wh per night
Why it mattersIf you're buying for storms that take the power for days, pay the gap for the Apex; if your outages end by bedtime, the extra capacity is insurance you'll never claim.
solar input
With refill ceilings that close, a sunny day pushes energy into either one at nearly the same rate. The difference shows on the gray day after, when the unit that banked 6,702Wh is still running and the one that banked 3,482Wh is rationing. Fast charging is the DELTA Pro 3's best trick, and it works best while the grid is up.
Solar input: DELTA Pro 3 2,600W, Apex 300 + B500K 2,400WDELTA Pro 3 reaches 0-80% in about 50 minutes using up to 7,000W of combined inputA3Usable capacity: DELTA Pro 3 3,482Wh, Apex 300 + B500K 6,702Wh
Why it mattersSolar-backed outage planners should value stored energy over charge speed, which favors the Apex; owners with a generator get real use from the DELTA Pro 3's fast charging.
Capacity can't separate them at 9% and 5%, and CPAP night is the one scenario on the page the DELTA Pro 3 takes. Its car socket is a reason that holds up on its own: a CPAP with a 12V DC cord plugs straight in, no adapter, no hub.
DELTA Pro 3: 4 USB-A, 2 USB-C at up to 100W and a 12V car socket on the unitApex 300: every USB and 12V/DC output requires the separately sold Hub D1B12CPAP Overnight uses 9% of the DELTA Pro 3 and 5% of the Apex 300 + B500K
Why it mattersApex buyers with a CPAP in the house or a USB-C-heavy household should budget for the Hub D1 up front; anyone who refuses to buy accessories has a real reason to take the DELTA Pro 3.
The specific dimensions that decide these two units — everything else is a tie.
Runtime: Will It Power Your Gear?
Selected because: The Apex has 6,702Wh usable to the DELTA Pro 3's 3,482Wh, and outage nights are what a home-backup buyer is paying for.
continuous output
Every load on this page runs about 1.9 times as long on the Apex, because that's the ratio of usable energy: 6,702Wh against 3,482Wh. The sharpest place it shows is a heavy day. Ask for 4,685Wh and the DELTA Pro 3 quits 1,203Wh short, while the Apex finishes with 2,017Wh still in the tank.
The DELTA Pro 3's one runtime-side edge is continuous output, 4,000W against 3,840W. Those 160W only matter when you're stacking big loads near the ceiling at once. Below it, the bigger tank simply lasts longer.
Lifetime Value
Selected because: The DELTA Pro 3 is the cheaper unit to buy and the costlier one per lifetime kilowatt-hour, a split that decides it for anyone cycling daily.
cost / lifetime kWh
The DELTA Pro 3 is the cheaper box and the more expensive battery. Fewer rated cycles of a smaller pack leave it less lifetime energy to spread its price across, and the Apex comes out at less than half the cost per lifetime kilowatt-hour.
That only pays out if you spend the cycles. A backup that sits full in a closet waiting for storms won't approach either rating, and for that buyer this section is a footnote. Cycle it daily, on solar time-shifting or at an off-grid cabin, and it becomes a second reason for the Apex: 16.4 years at a cycle a day against 11.
What the Specs Don't Tell You
Selected because: Weight, noise ratings and surge all fire on this pair, and the noise ratings need careful reading before they sway anyone.
rated cycles
Read the noise card before it sways you. The two ratings come from different makers measuring different ways, and three reviews describe the Apex's fans as even and tame under loadB1B2B13, though those reviews may cover a sibling configuration. Weight is real but paid once, on install day, and both units are built to stay put.
Surge is the card that can change a purchase, and it reads the other way from how the two numbers look. The DELTA Pro 3 publishes a 6,000W surge, 1.5 times its continuous rating. The Apex's 7,680W is Power Lifting, BLUETTI's mode for running a resistive heater or kettle above the 3,840W inverter, slowly; it is not a surge peak, and BLUETTI publishes none for the unit. For a well pump or an AC compressor's startup kick, check your heaviest motor's startup draw against 6,000W on the DELTA Pro 3 and against 3,840W continuous on the Apex.
Brand Trust
Selected because: BLUETTI's support is the less consistent of the two brands, and that matters more on a unit with a thin field record.
BLUETTI's support is the weak link this pick carries. Our brand profile rates it the least consistent in the category, email-first with time-zone delays, against EcoFlow's US phone, email and chat line. It weighs more than usual here because the Apex's field record is thin and includes firmware-update faultsB0B7B9.
Two moves narrow the gap. Buy the Apex direct from BLUETTI, where support outcomes tend to be better, and register it, since the full 5-year term depends on buying direct or registering. EcoFlow's own catch is that it offers no parts or service once the warranty ends; buying through Costco or Amazon adds a stronger return safety net.
Strengths & trade-offs
EcoFlow DELTA Pro 3
Strengths
- +Costs $500 less
- +Lighter by 69.5 lb
- +Higher AC output
- +Faster solar charging
Trade-offs
- –Very heavy unit that may be difficult for one person to lift.
- –Shorter-lived battery — rated for 4,000 charge cycles vs the Apex 300 + B500K's 6,000, so it wears out sooner.
BLUETTI Apex 300 + B500K
Strengths
- +Larger battery capacity
- +Rated for 6,000 charge cycles — much longer battery lifespan
Trade-offs
- –Significantly heavier (+69.5 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
Neither unit
Neither. The 2,100Wh weekend is trivial for both batteries, but the DELTA Pro 3 is a 112.4 lb box and the Apex pair weighs 183 lbs across two, and neither is going to a campsite. Buy a portable for this.
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 + B500K
Both finish the night easily; the Apex does it at 25% used against 47%, leaving enough for 3.1 more nights to the DELTA Pro 3's 1.1. If the outage runs into a third day, only one of these is still going without sun.
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
Either unit
Capacity can't split them: the night uses 9% of the DELTA Pro 3 and 5% of the Apex. The DELTA Pro 3 takes it, and its 12V car socket is a reason you can count on, since a CPAP with a DC cord plugs straight in while 12V on the Apex needs the Hub D1. The two published noise ratings aren't measured the same way, so don't decide on them.
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 + B500K
Both clear a full workday without strain, 14% used on the Apex and 26% on the DELTA Pro 3. The Apex wins on reserve; if this is your only use, it's a win you'd never notice.
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
Neither unit
Neither travels. 670Wh is nothing to either battery; getting 112.4 or 183 lbs into a parking lot is the actual problem.
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 + B500K
The DELTA Pro 3 runs out 1,203Wh short of a 4,685Wh day; the Apex finishes with 2,017Wh to spare. Just know that 183 lbs in two boxes is a permanent van install, not something you load for each trip.
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 + B500K runs 32.7h vs 17h.
$3,299 list · direct from BLUETTI
Planning for more than this? Describe your whole setup and get it sized →
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 0–446.8hComfort & Convenience
Makes off-grid life actually enjoyablescale 0–89.4hHigh-Draw Appliances
These reveal the real limitsscale 0–6.7h¹ 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
November 1, 2026
Verdict: the BLUETTI Apex 300 + B500K
Buy the Apex 300 + B500K. The extra $500 buys nearly a second DELTA Pro 3's worth of battery, rated for half again as many cycles, and that is the purchase a home-backup buyer is actually making: more nights before the house goes dark. The DELTA Pro 3 is the right call in one situation, and it's a common one: when 4,096Wh already outlasts your longest outage. Then its lower price, single 112.4 lb box, fast multi-input chargingA3 and USB and 12V outputs on the unit (the Apex needs the separately sold Hub D1 for thoseB12) make it the better deal. Confidence stops at 6 because the Apex's field record is thin and partly about other configurationsB0, what exists includes firmware-update faultsB7B9, and BLUETTI's support is the less consistent of the two brands.
Editor-assigned confidence, based on cited owner research and spec analysis.
List prices as of November 1, 2026. The links below open EcoFlow's and BLUETTI's current prices.
$3,299.00 · direct from BLUETTI
Last checked 28 days ago. Prices move — check before you buy.
or check the DELTA Pro 3 price$2,799.00 list
Written by Gunner Gustafson, Whole-Home Backup Tester · Station Arena Test Desk · Updated November 1, 2026
Black Friday · 26 days out
Prices to beat:DELTA Pro 3 $2,399Apex 300 + B500K $3,299
The lowest we have recorded for each. We have never seen the Apex 300 + B500K discounted, so any real cut on it would be a first.
Measured Data
Benchmark scores and the full spec record, side by side.
Benchmark scores
Not rated for both units (minimum threshold unmet): RV Living, Solar Generator.
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 Pro 3 rates 3.9/5 (37th percentile of 20 Home Backup-class units), and Apex 300 + B500K rates 3.5/5 (11th percentile of 37 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.
Paid Once, on Install Day
The DELTA Pro 3 is a single 112.4 lb box, a two-person lift. The Apex 300 + B500K totals 183 lbs across two boxes, so nobody lifts it all at once, but you're positioning two heavy pieces instead of one. Both are built to stay put, so the 70.6 lb difference is something you pay getting them into place, not every week.
Two Ratings, Two Rulers
BLUETTI publishes 45dB for the Apex 300 + B500K and EcoFlow publishes 30dB for the DELTA Pro 3. Neither is a measurement at your load, and the two makers don't publish on the same basis, so the difference isn't one you can count on hearing. If the unit is going in a bedroom or a home office, find a measurement of both at the same load before noise decides anything.
Apex 300 + B500K: Power Lifting to 7,680W
The Apex 300 + B500K has BLUETTI's Power Lifting mode, which runs a resistive appliance rated up to 7,680W from its 3,840W inverter. It does that by delivering less power than the appliance asks for, not more than the inverter has: the heater still works, it just heats more slowly. Two things follow. BLUETTI scopes the mode to purely resistive loads — a heater, a kettle, an incandescent lamp — so it does nothing for a fridge compressor, a pump or a power tool, and this record publishes no surge figure at all, so read the mode as a resistive-load feature rather than as starting ability. And it is not a reason to size down, because running a load that big from 7,885Wh is a short session either way. Genuinely useful if a heater or a kettle is why you're buying; beside the point otherwise. The DELTA Pro 3 publishes no equivalent.
Warranty: No Difference
Both units carry the same 5-year warranty, so coverage isn't a tiebreaker here. The Apex 300 + B500K'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.
Nearly Three Times the Lifetime Energy
The Apex 300 + B500K is rated for 6,000 cycles and the DELTA Pro 3 for 4,000, and each Apex cycle is 7,885Wh against 4,096Wh. Multiply through and the Apex is rated to deliver about 47,309kWh over its life against 16,384kWh, 2.9 times as much. Both ratings are minimums, and a pack that reaches its count keeps working at reduced capacity.
Full record above — the Test Desk pick is the Apex 300 + B500K.
Check Apex 300 + B500K price →or check the DELTA Pro 3 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 Pro 3 is cheaper to buy, but the Apex 300 + B500K is cheaper to own. At $0.07/kWh over its lifetime vs $0.17/kWh, the Apex 300 + B500K's higher cycle life and capacity make each dollar go further over the years.
Delivers each lifetime kWh for $0.10 less — check the Apex 300 + B500K price →
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-based phone/email/chat support (1-800-368-8604). Experiences are polarized — many report hassle-free prepaid-label replacements, but others report long waits and refurbished units sent for new claims. Pro tip: buying from Costco or Amazon gives you a stronger return safety net.
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 top of the range sit two whole-home paths: the TITAN line, one 5 kWh unit that grows to 30 kWh, and the DELTA Pro Ultra platform, which stacks batteries and inverters further — flagship paths, not line-wide features.
Worth knowing
Tested subscription paywalls for advanced app features in early 2025 before community backlash paused the plan. No parts or service offered out of warranty.
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 space. Heavily email-based with China timezone delays. Some users get smooth, efficient service; others report weeks of troubleshooting runarounds, being offered discounts on new units instead of repairs, and confusing third-party purchase claim processes. Buying direct from Bluetti's website tends to produce better support outcomes.
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
Customer support inconsistency is the #1 risk factor. Older/discontinued units may become unrepairable — no spare parts policy for some models. Some reports of erratic communication from support agents.
Analyst note
EcoFlow has the US phone line and the biggest owner community; BLUETTI's support is email-first and, by our brand profile, the least consistent in the category. If you buy the Apex, buy it from BLUETTI directly, where support outcomes tend to be better. EcoFlow's own catch is that it offers no parts or service once the warranty ends.
Growth path
DELTA Pro 3
EXPANDABLESupports EcoFlow expansion batteries, so you can add capacity later without replacing the base unit — useful if your needs may climb past 4,096Wh.
Accepts up to 2,600W of solar. Enough for a serious multi-panel array.
Generous port selection supports complex multi-device setups.
Expansion batteries are EcoFlow-specific. You're investing in the EcoFlow ecosystem.
Apex 300 + B500K
EXPANDABLESupports BLUETTI expansion batteries, so you can add capacity later without replacing the base unit — useful if your needs may climb past 7,885Wh.
Accepts up to 2,400W of solar. Enough for a serious multi-panel array.
Limited ports. You'll likely need a power strip or splitter.
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
Both expand, so neither locks you out of growth — decide on capacity, price, and the rest, not the expansion checkbox.
What Owners Report
Patterns from published owner reports and long-term reviews — every claim cited to its source below.
EcoFlow DELTA Pro 3
Our DELTA Pro 3 coverage comes from review sites and retailer listings rather than long-term ownersA0, so read it as a reviewer consensus, not a field record. The consensus is warm: reviewers call it a gold-standard whole-home backup unitA4, and the praise lands on the 4,096Wh LFP pack, 4,000W dual-voltage output and room to expand to 48kWhA1.
Charging is the standout. Reviewers clock 0-80% in about 50 minutes on up to 7,000W of combined input and a full charge in roughly 90 minutesA3, and the cells carry a 4,000+ cycle rating to 80% with an IP65 battery ratingA2. Nothing in the coverage reads as a recurring fault, which with sources this thin says as much about the sources as the unitA0.
“4,096Wh LFP battery with 4,000W continuous AC output (6,000W with X-Boost) and dual-voltage 120V/240V, expandable to 48kWh.”
Sources
ecoflow.com · amazon.com · homedepot.com · thepowerpick.com · outboundpower.com · techradar.com · thesolarlab.com
BLUETTI Apex 300 + B500K
Field data on this exact pairing barely exists. Our research found no Reddit discussion, no reports past six months of ownership, and no source confirming the Apex 300 + B500K combination specifically; most commentary covers the bare Apex 300 or the B300K pairingB0. Everything below may describe a sibling configuration, so read it as character, not spec.
Where it agrees, it's on fans: three independent reviews describe them as tame and even under load, with no pitch or rattleB1B2B13. The friction is firmware. Owner threads show updates locking a unit in Backup mode, breaking the app's update check and triggering an E004 inverter faultB7B8B9, with some resolved by later updatesB8B10. Owners running several Apex 300s in parallel report uneven charge rates and lean on unofficial workaroundsB3B4. One reviewer could hardly carry the Apex 300 more than a few feetB11, and the unit has no USB or DC outputs without the Hub D1B12. One owner's take was simpler: it works with external batteries, and the 240V output is greatB5.
“Turns out the Apex 300's noise control is on par with the quietest power stations on the market, like those on offer from EcoFlow and DJI.”
Sources
bluettipower.com
Sources & Research Notes
Every owner claim in this report is traceable to a published source. The bracketed references above resolve here.
Recurring owner themes
- Huge 4,096Wh LFP capacity, 4,000W dual-voltage output, very fast charging, and big expandability are the standout praise; it's heavy at ~113 lbs. [DELTA Pro 3 · 2 entries]
- Multiple independent reviewers describe the dual-fan cooling as noticeably quiet/even for a unit of this output class, even under load. [Apex 300 + B500K · 3 entries]
- Firmware and app updates have repeatedly caused mode-lock, download failures, or inverter error codes; several threads show the issue eventually resolved after further updates or support contact. [Apex 300 + B500K · 4 entries]
- When running multiple Apex 300 units or expansion batteries in parallel, owners report uneven charge rates between units, with community-devised (unofficial) workarounds needed to keep them in sync. [Apex 300 + B500K · 2 entries]
- The stripped-down, modular design draws criticism for real-world handling: extreme weight makes it hard to move, and lack of native USB/DC ports forces reliance on a separate paid hub accessory. [Apex 300 + B500K · 2 entries]
- A1
“4,096Wh LFP battery with 4,000W continuous AC output (6,000W with X-Boost) and dual-voltage 120V/240V, expandable to 48kWh.”
ecoflow.com / amazon.com — DELTA Pro 3 · 2026 · [positive]
- A2
“LiFePO4 rated for 4,000+ cycles to 80% (10+ years), with an IP65 battery rating.”
homedepot.com / thepowerpick.com — DELTA Pro 3 review · 2026 · [positive]
- A3
“Multi-charge technology reaches 0-80% in about 50 minutes using up to 7,000W input, with a full charge in roughly 90 minutes; up to 2,600W solar.”
outboundpower.com / techradar.com — DELTA Pro 3 review · 2026 · [positive]
- A4
“Weighs about 113.5 lbs; reviewers call it a gold-standard whole-home backup unit for 2026.”
techradar.com / thesolarlab.com — DELTA Pro 3 review · 2026 · [positive]
- B1
“Turns out the Apex 300's noise control is on par with the quietest power stations on the market, like those on offer from EcoFlow and DJI.”
The Solar Lab — "Bluetti Apex 300 Review: Cheap, Practical Home Backup?" · unknown · [positive]
- B2
“Some units sound like small jet engines under load, but the Apex 300's fans are relatively tame.”
Techspective — "Bluetti Apex 300 with B300K Review" · 2025-09 · [positive]
- B3
“The Apex 300 have some major charging problems... When the units are charging from the grid they charge at different rates and not together.”
DIY Solar Power Forum — "Bluetti Apex 300 problems" · 2025-09 · [negative]
- B4
“I have found a simple way to get around some of the solar charging limitations with multiple APEX 300s hooked up in parallel... So far, I have not had any problems with my setup.”
DIY Solar Power Forum — "Bluetti Apex 300 problems" · 2025-09 · [mixed]
- B5
“So far so good. Works with external batteries. For small applications the solar available works OK. For me the 240V output is great.”
DIY Solar Power Forum — "Bluetti Apex 300 launched today… anyone have thoughts?" (page 2) · 2025-05 · [positive]
- B7
“I updated my Apex 300 to the latest firmware yesterday. Now it's stuck in 'Backup' mode... when I go into the app to try to change it back, it flashes to...”
BLUETTI Community — "Apex 300 stuck in Backup mode after last firmware update" · 2025-11 · [negative]
- B8
“There was an update on my Apex 300 a few days ago IOT v8026.12... Problem is every time I connect to the power st[ation]... Edit - This seems fixed now hooray!”
BLUETTI Community — "Check For Update App issue" · 2025-09 · [mixed]
- B9
“After the update completed, the charging stopped and I received Error 004... I have error E004 Inverter Output Failure.”
BLUETTI Community — "Error E004 Apex 300" · 2025-11 · [negative]
- B10
“I had a power outage in the middle of the night, so I hooked everything (Hub A1 and all 300's) back up and now HA is populating. YEA!!!”
GitHub bluetti-official/bluetti-home-assistant — "APEX 300 and Hub A1 now working" (Issue #95) · 2026-05 · [mixed]
- B11
“it's so heavy I can hardly carry it more than a few feet at a time and have been unable to lift it onto a table.”
T3 — "Bluetti Apex 300 review: transform your off-grid life" · 2025-11 · [negative]
- B12
“The Apex 300 doesn't have USB ports, DC ports, or much of anything beyond its six AC plugs and high-voltage connectors.”
The Solar Lab — "Bluetti Apex 300 Review: Cheap, Practical Home Backup?" · unknown · [negative]
- B13
“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" · 2025-05 · [positive]
Research compiled November 1, 2026.
Who Should Buy Which
Buy the DELTA Pro 3 if you…
- →Your outages are measured in evenings. A 1,645Wh blackout night leaves the DELTA Pro 3 with 1,837Wh in hand, and you keep $500 for something else.
- →You have a generator or dependable grid power to recharge from, and you want the fast multi-input charging reviewers clock at 0-80% in about 50 minutesA3.
- →Someone in the house sleeps on a CPAP with a 12V DC cord, or the household lives on USB-C, and you want those plugs on the box instead of in a hub you buy separately.
Buy the Apex 300 + B500K if you…
- →You're buying for the storm that takes the power for days: 6,702Wh usable carries a 1,645Wh blackout night four times over before you need sun.
- →You'll cycle it every day, on solar time-shifting or at an off-grid cabin, where 6,000 rated cycles of a bigger pack pull away from the DELTA Pro 3's 4,000.
- →You'll buy direct from BLUETTI, register it, and accept a newer unit whose field record is still thinB0.
If neither fits
If the job is a fridge, a router and phones through an evening outage, both are overkill: that 1,645Wh night uses under half of even the smaller unit. And if you want power at a campsite or a tailgate, neither one travels; close this tab and shop portable units one person can lift.
The Bottom Line
Buy the Apex 300 + B500K. The extra money buys nearly a second DELTA Pro 3's worth of battery, and in a home-backup unit that converts straight into nights: about four on our blackout profile against about two. With solar ceilings 200W apart, the bigger tank is also the one still running after a cloudy day.
Take the DELTA Pro 3 instead if 4,096Wh already outlasts your longest outage, or if you want USB and 12V on the box without buying the Hub D1. Otherwise, pay the difference once and bank the extra nights.
Frequently Asked Questions
Answers drawn from the spec record and cited owner research.
Is the BLUETTI Apex 300 + B500K worth the extra cost over the EcoFlow DELTA Pro 3?
For outage backup, yes. The $500 difference buys 3,789Wh more battery (7,885Wh against 4,096Wh) and 2,000 more rated cycles, which on our blackout profile means about four nights of stored power instead of two. If your outages rarely run past an evening, the DELTA Pro 3 already covers them and the extra capacity sits unused.
Does the BLUETTI Apex 300 have USB ports?
Not on the unit. Every USB-C, USB-A and 12V/DC output on the Apex 300 requires the separately sold Hub D1; without it, you charge phones through its six AC outlets with wall adapters. The DELTA Pro 3 has 4 USB-A, 2 USB-C at up to 100W and a 12V car socket built in.
Which is quieter, the DELTA Pro 3 or the Apex 300 + B500K?
The spec sheets can't settle it. EcoFlow publishes 30dB and BLUETTI 45dB, but the two makers don't publish on the same basis and neither figure describes your load, so the gap isn't one you can count on hearing. Three reviews describe the Apex's fans as tame and even under load, though they may cover a sibling configuration.
How long will the DELTA Pro 3 and Apex 300 + B500K last in a power outage?
On our 8-hour blackout profile, which draws 1,645Wh, the DELTA Pro 3 finishes with 1,837Wh left, enough for 1.1 more nights, and the Apex finishes with 5,057Wh, enough for 3.1 more. Both figures use the same 85% usable derate, so the comparison is like for like.
Can you expand the DELTA Pro 3 to match the Apex 300 + B500K?
Yes. The DELTA Pro 3 takes EcoFlow expansion batteries, up to 48kWh in total per EcoFlow's listing, so capacity alone isn't a permanent gap. But that's a second purchase on top of the DELTA Pro 3's price, while the Apex 300 + B500K already arrives as a base unit plus an expansion battery.
Brand matchup
EcoFlow vs BLUETTI: measured across every matchup →Where to buy
EcoFlow DELTA Pro 3
$2,799.00
$2,799.00 · direct from EcoFlow
Last checked 28 days ago. Prices move — check before you buy.
BLUETTI Apex 300 + B500KPick
$3,299.00
$3,299.00 · direct from BLUETTI
Last checked 28 days ago. Prices move — check before you buy.
Prices may vary by retailer and are subject to change.