Head-to-head test
EcoFlow DELTA 3 Ultra vs BLUETTI Apex 300 + B300K
The DELTA 3 Ultra costs $1,400 less than the Apex 300 + B300K for the same 4,000-cycle chemistry and a 3,600W inverter, and it's cheaper to own at $0.10 per lifetime kWh against $0.13 — the only place that math breaks is Van Life Daily, where its 3,072Wh tank needs 179% of itself to finish the day.
Written by Gunner GustafsonUpdated
Whole-Home Backup Tester, Station Arena Test Desk
EcoFlow
DELTA 3 Ultra
5,362Power Score · The AC & Fridge Zone
$1,299.00 list · direct from EcoFlow
BLUETTI
Apex 300 + B300K
6,552Power Score · The AC & Fridge Zone
$2,599.00 list · direct from BLUETTI
Spec deltas
The EcoFlow DELTA 3 Ultra costs $1,199; the BLUETTI Apex 300 + B300K costs $2,599 — a $1,400 gap for two units built around a similar 3,600-3,840W inverter class.
The price gap isn't just sticker shock. It shows up in lifetime cost too: $0.10 per kWh delivered for the DELTA 3 Ultra against $0.13 for the Apex, backed by a higher 4,000-cycle rating against 3,500. It's also the lighter unit at 77.2 lbs against 148.8, and the quieter one at 30dB against 45dB under load.
The one place the price gap stops paying off is a full day's real energy draw. Van Life Daily needs 4,685Wh, and the DELTA 3 Ultra's 3,072Wh tank comes up 179% short of covering it alone — the scenario the Apex was effectively built for.
What the Numbers Reveal
Each conclusion stated first — the numbers behind it on one line, the full analysis below.
rated cycles
A three-cent-per-kWh gap compounds over thousands of cycles into real money, and here it runs in the direction of the cheaper unit, not against it.
The DELTA 3 Ultra costs $1,199 and is rated for 4,000 cycles; the Apex 300 + B300K costs $2,599 and is rated for 3,500 cyclesLifetime cost works out to $0.10 per kWh for the DELTA 3 Ultra against $0.13 for the Apex
Why it mattersBuyers who don't specifically need the Apex's larger tank are paying a real premium for capacity they may not use, on top of a lower cycle count.
Capacity
Every other tested scenario (Weekend Camping, the 8-Hour Blackout, Remote Workday, Tailgate Party) leaves the DELTA 3 Ultra with real headroom; only the full-day use case exposes the tank size.
Van Life Daily needs 4,685Wh; the DELTA 3 Ultra's 3,072Wh tank needs 179% of its own capacity to cover that dayThe Apex 300 + B300K's 5,529.6Wh tank covers the identical day at exactly 100%
Why it mattersBuyers should map their actual daily draw against 3,072Wh before deciding — under that line, the DELTA 3 Ultra's price and cycle advantages dominate; over it, only the Apex finishes the job.
weight
For anyone using this outside a single fixed installation, the DELTA 3 Ultra's portability advantage compounds with its price advantage rather than trading off against it.
The DELTA 3 Ultra weighs 77.2 lbs and is rated 30dB under load; owners praise its telescoping handle and wheels for making it 'effortless to cart around' despite the weightA14The Apex 300 + B300K weighs 148.8 lbs stacked and is rated 45dB, and reviewers call it 'not something you'll casually lug to a picnic'B5
Why it mattersBuyers who need to move the unit between a garage, a vehicle, and a campsite should treat the DELTA 3 Ultra's weight and noise numbers as decisive, not just a bonus on top of the lower price.
The specific dimensions that decide these two units — everything else is a tie.
Lifetime Value
Selected because: Widest cost-per-kWh gap in this comparison set, at a higher cycle rating too.
cost / lifetime kWh
The DELTA 3 Ultra delivers energy at $0.10 per lifetime kWh against $0.13 for the Apex — the widest gap in this comparison set — while also carrying a higher 4,000-cycle rating against 3,500. It costs $240 per warranty year against $520.
This isn't a case of paying less and getting less durability. The cheaper unit here is also the longer-rated one; the Apex's premium buys capacity, not longevity.
Your Life, Your Pick
Selected because: DELTA 3 Ultra covers everything but Van Life Daily, the one clean loss.
The DELTA 3 Ultra covers Weekend Camping, the 8-Hour Blackout, CPAP Overnight, Remote Workday, and Tailgate Party with real margin — even its tightest of those, the 8-Hour Blackout, uses only 63% of its tank.
Van Life Daily is the exception: it needs 179% of the DELTA 3 Ultra's own capacity, which the tank simply doesn't have. The Apex covers the identical day at exactly 100% of its larger tank.
Portability & Form Factor
Selected because: Nearly half the weight and 15dB quieter, reinforcing the value case.
weight
At 77.2 lbs against the Apex's 148.8 lbs stacked, the DELTA 3 Ultra is under half the weight, and owners describe its telescoping handle and wheels as making it effortless to cart around despite the heftA14.
It's also the quieter unit by 15dB, 30dB against 45dB under load — a meaningful gap for anywhere the noise is heard up close.
What the Specs Don't Tell You
Selected because: Weight, noise, and warranty cards fire, all reinforcing the same direction.
rated cycles
Weight and noise both fire in the DELTA 3 Ultra's favor here — lighter and quieter, with nothing on the Apex's side to offset it in this category. The UPS behavior is comparable: both switch over inside 10ms.
The warranty card is informational: both carry 5-year coverage, and the DELTA 3 Ultra's lower cost per warranty year ($240 against $520) tracks directly with its lower purchase price.
Strengths & trade-offs
EcoFlow DELTA 3 Ultra
Strengths
- +Costs $1,300 less
- +Lighter by 71.6 lb
Trade-offs
- –No major technical downsides compared to rival.
BLUETTI Apex 300 + B300K
Strengths
- +Larger battery capacity
- +Higher AC output
- +Faster solar charging
Trade-offs
- –Substantially more expensive (+$1,300) than the DELTA 3 Ultra.
- –Significantly heavier (+71.6 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
Apex 300 + B300K
The DELTA 3 Ultra cuts it close at 80%. One cold night or an unexpected device and you're rationing power. The Apex 300 + B300K finishes at 45%, leaving real headroom for spontaneous use. If you camp in variable weather, that buffer keeps you relaxed instead of checking your battery app every 20 minutes.
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 + B300K
Both survive, but the Apex 300 + B300K finishes at just 35% used. That's enough reserve for a second blackout night. The DELTA 3 Ultra at 63% leaves little margin if the outage runs longer than expected. In storm-prone areas, that remaining capacity is insurance.
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
Both are wildly overqualified for CPAP. You're using 12% or less. Save your money and buy whichever is cheaper; the extra capacity is completely wasted on a 40W overnight load. Put the savings toward a second battery for multi-night trips.
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 + B300K
The Apex 300 + B300K gives you a comfortable buffer at 19%. Enough to work late, join extra video calls, or charge a second device without worry. The DELTA 3 Ultra at 35% works but leaves less room for the unexpected. For daily remote work, that peace of mind matters.
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
Apex 300 + B300K
Both handle game day, and the Apex 300 + B300K does it with more in reserve — 14% used against 26%. Tailgating is a light load, so that headroom counts for less here than the 72 lbs you'll actually carry across the parking lot.
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 + B300K
The DELTA 3 Ultra needs 179% of its own tank to cover a full van-life day — it simply can't finish without a mid-day recharge. The Apex 300 + B300K covers the identical day at exactly 100%, the one scenario in this comparison where the price gap fully explains itself.
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 six 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 + B300K runs 22.9h vs 12.7h.
$2,599 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 0–313.3hComfort & Convenience
Makes off-grid life actually enjoyablescale 0–62.7hHigh-Draw Appliances
These reveal the real limitsscale 0–4.7h¹ 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
July 15, 2026
Verdict: the EcoFlow DELTA 3 Ultra
At $1,199, the DELTA 3 Ultra is $1,400 cheaper than the $2,599 Apex 300 + B300K, and the cost-per-lifetime-kWh gap is the widest in this whole comparison set: $0.10 against $0.13, with 4,000 rated cycles against 3,500. It's also lighter (77.2 lbs against 148.8) and quieter (30dB against 45dB under load). The place it loses outright is Van Life Daily — its 3,072Wh tank needs 179% of its own capacity to cover a 4,685Wh day, where the Apex covers the same day at exactly 100%. For any use case that fits inside roughly 3,072Wh, which covers camping, blackouts, remote work, and tailgating with real margin per the tested scenarios, the DELTA 3 Ultra is the more efficient buy by a wide margin. Only full-time van life or an equivalent full-day draw should push a buyer to the Apex instead.
Editor-assigned confidence, based on cited owner research and spec analysis.
List prices as of July 15, 2026. The links below open EcoFlow's and BLUETTI's current prices.
$1,299.00 list · direct from EcoFlow
or check the Apex 300 + B300K price$2,599.00 list
Written by Gunner Gustafson, Whole-Home Backup Tester · Station Arena Test Desk · Updated July 15, 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, 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 5.0/5 (99th percentile of 25 Large-class units), and Apex 300 + B300K rates 4.4/5 (67th percentile of 16 Home Backup-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.
77.2 Pounds Against 148.8
The DELTA 3 Ultra is under half the Apex's stacked weight, and owners credit its wheels and telescoping handle with making that manageable solo. The Apex needs a cart or a fixed spot.
30 Decibels Against 45
The DELTA 3 Ultra is the quieter unit by 15dB under load, a gap reviewers consistently notice even when the inverter is pushed toward its maximum output.
Same Five Years, Different Price Tags
Both carry 5-year coverage. The DELTA 3 Ultra costs $240 per warranty year against $520 for the Apex, tracking directly with its lower purchase price rather than a difference in coverage.
Full record above — the Test Desk pick is the DELTA 3 Ultra.
Check DELTA 3 Ultra price →or check the Apex 300 + 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
Both units have similar long-term ownership costs ($0.11/kWh vs $0.13/kWh). The price difference is what you see on the sticker — neither is a hidden bargain or rip-off.
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. Supports up to 180kWh modular expansion with DELTA Pro Ultra X.
Worth knowing
The Oct 2025 DELTA Max 2000 recall (overheating/fire risk, 6 incidents) is worth noting. Also 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 (Apex 300, 3072Wh). 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. Full LFP standardization across lineup (3,500-6,000+ cycles). 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 positions itself as a mid-to-premium brand with stronger support infrastructure, while BLUETTI competes on value. The question is whether the EcoFlow ecosystem and support premium is worth it for your use case.
Growth path
DELTA 3 Ultra
EXPANDABLESupports EcoFlow expansion batteries, so you can add capacity later without replacing the base unit — useful if your needs may climb past 3,072Wh.
Accepts up to 1,600W 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 + B300K
EXPANDABLESupports BLUETTI expansion batteries, so you can add capacity later without replacing the base unit — useful if your needs may climb past 5,530Wh.
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
Both expand, but the Apex 300 + B300K's higher solar ceiling (2,400W vs 1,600W) gives it the stronger off-grid growth path — more panels can feed a bigger bank as it grows.
What Owners Report
Patterns from published owner reports and long-term reviews — every claim cited to its source below.
EcoFlow DELTA 3 Ultra
Owner and reviewer commentary consistently praises how quiet this tier of DELTA 3 stays under real load, with no annoying or distracting fan noise even pushing the inverter toward its maximum outputA1A2, and testers report solid UPS behavior — no dips or shutdowns switching from wall powerA4A6. One reviewer ran an eight-hour remote workday on laptop, desktop, and monitors and still had 40% leftA8.
The honest catch is weight: reviewers repeatedly call it 'thunderous' for its class at roughly 74-77 lbs, though the telescoping handle and wheel design get credit for making that weight manageableA10A14. This is a recently released product, and coverage is skewed toward professional review-site testing of the closely related 'Ultra Plus' variant rather than long-term forum threads specific to the base 'Ultra' — treat field data here as thinner and less settled than a mature product line.
“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 + B300K
Where reviewers rate the Apex 300 + B300K highest is real household load testing: one wash cycle drew it from 100% down to 65% in about an hour, with a heat pump dryer run afterward bringing it to 20% over roughly 90 more minutesB9B10 — numbers that back up the claim it can genuinely stand in for a generatorB4.
As elsewhere in this bundle's coverage, this is early-adopter review territory rather than a mature owner community, so weight that accordingly. The consistent structural gripe holds here too: no USB or DC ports without the separate roughly $300 Hub D1 accessoryB1B2, which is worth factoring into the already-large price gap against the DELTA 3 Ultra.
“The Apex 300 doesn't have USB ports, DC ports, or much of anything beyond its six AC plugs and high-voltage connectors.”
Sources
thesolarlab.com · techspective.net · digitalreviews.net · thesolarpit.com · cleantechnica.com · trustedreviews.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
- 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]
- Reviewers consistently flag that the base Apex 300 has no USB/DC ports and requires a separate paid Hub D1 accessory, which some feel is overpriced for what it offers. [Apex 300 + B300K · 3 entries]
- Multiple sources note the extreme weight/bulk of the stacked Apex 300 + B300K system, making 'portable' a stretch despite handles/trolley options. [Apex 300 + B300K · 2 entries]
- Reviewers praise fast recharge and the system's ability to genuinely replace a generator for home backup and heavy loads like washers/dryers. [Apex 300 + B300K · 4 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]
- 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]
- 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]
- A10
“Weighing in at a thunderous 74 pounds, the Ultra is not considered lightweight by any standards.”
appleinsider.com — EcoFlow Delta 3 Ultra Plus review: Premium, but solid power · 2025-11-16 · [mixed]
- A14
“The sturdy telescoping handle and wheels make it effortless to cart around, and if you do have to lift its admittedly somewhat hefty 74 lbs, grab handles are well placed for the task.”
popsci.com — EcoFlow DELTA 3 portable power station series first impressions · 2025-09-29 · [positive]
- B1
“The Apex 300 doesn't have USB ports, DC ports, or much of anything beyond its six AC plugs and high-voltage connectors.”
thesolarlab.com — Bluetti Apex 300 Review: Cheap, Practical Home Backup? · unknown (2025/2026) · [mixed]
- B2
“That Bluetti D1 Power Hub that gives you your DC and USB ports costs about $300, which is a steep price for what you're getting.”
thesolarlab.com — Bluetti Apex 300 Review: Cheap, Practical Home Backup? · unknown (2025/2026) · [negative]
- B4
“It's one of the few systems I've tested that feels like it could genuinely replace a generator, without the noise, fumes, or maintenance.”
techspective.net — Bluetti Apex 300 with B300K Review · 2025-09-21 · [positive]
- B5
“Stacked, you're near 150 pounds of lithium iron phosphate and inverter muscle—movable with the built-in handles or a trolley... but not something you'll casually lug to a picnic.”
techspective.net — Bluetti Apex 300 with B300K Review · 2025-09-21 · [mixed]
- B9
“Results: 1 wash took about 1 hour and drained the Apex from 100% down to 65%.”
digitalreviews.net — Bluetti Apex 300 Power Station Tests (Australia) Part II · 2025-09 · [positive]
- B10
“Just for fun we then turned on our heat pump dryer to see that over 1½ hours it would further drain it down to 20%.”
digitalreviews.net — Bluetti Apex 300 Power Station Tests (Australia) Part II · 2025-09 · [mixed]
Research compiled July 15, 2026.
Who Should Buy Which
Buy the DELTA 3 Ultra if you…
- →Your daily or per-outage draw stays under roughly 3,072Wh, which covers camping, a multi-hour blackout, a remote workday, or a tailgate with real margin to spare.
- →You want the unit that moves easily between a garage, a vehicle, and a campsite — 77.2 lbs and wheels against 148.8 lbs stacked.
Buy the Apex 300 + B300K if you…
- →You need to cover a full day's real energy use, like full-time van life — the DELTA 3 Ultra's tank needs 179% of its own capacity to do the same job.
- →You specifically need the larger continuous capacity and are willing to pay $1,400 more and carry nearly double the weight for it.
If neither fits
If the real job is topping off phones and a laptop over a weekend, both of these are far more unit than the task needs — a sub-$500 station from either brand covers it for a fraction of either price.
The Bottom Line
For most buyers, the DELTA 3 Ultra wins this one clearly: $1,400 cheaper, cheaper per lifetime kWh at $0.10 against $0.13, a higher cycle rating, and lighter and quieter to boot. Every tested scenario except one leaves it with real capacity to spare.
The one exception is the exception that matters if it's your use case: a full day's real energy draw, where the DELTA 3 Ultra's tank needs 179% of its own capacity to finish and the Apex 300 + B300K covers the identical day at exactly 100%. Know which buyer you are before the price tag decides for you.
Frequently Asked Questions
Answers drawn from the spec record and cited owner research.
DELTA 3 Ultra or Apex 300 + B300K — which is the better value?
The DELTA 3 Ultra, for most buyers. It's $1,400 cheaper, cheaper to own at $0.10 per lifetime kWh against $0.13, and carries a higher 4,000-cycle rating. It only falls short on a full day's real energy draw, like van life, where its tank needs 179% of its own capacity to finish the job.
Can the DELTA 3 Ultra run a full day of van life?
Not on a single charge. A full van-life day needs about 4,685Wh; the DELTA 3 Ultra's 3,072Wh tank needs 179% of its own capacity to cover that, meaning a mid-day recharge is required. The Apex 300 + B300K covers the same day at exactly 100%.
Is the DELTA 3 Ultra durable enough to be a real budget option here?
Yes on paper — it carries a 4,000-cycle rating against the Apex's 3,500, so the lower price isn't trading away durability. It's a newer product with thinner long-term field data than a mature line, which is worth knowing rather than a reason for concern by itself.
Which one is lighter and easier to move around?
The DELTA 3 Ultra, at 77.2 lbs against the Apex 300 + B300K's 148.8 lbs stacked — under half the weight, and owners credit its telescoping handle and wheels with making that weight manageable.
What's the honest downside of the Apex 300 + B300K here?
Price and weight, mostly. It costs $1,400 more, weighs nearly double, and the base unit ships without USB or DC ports unless you add a roughly $300 Hub D1 accessory. The tradeoff is a tank large enough to finish a full van-life day where the DELTA 3 Ultra can't.
Where to buy
EcoFlow DELTA 3 UltraPick
$1,299.00
$1,299.00 list · direct from EcoFlow
BLUETTI Apex 300 + B300K
$2,599.00
$2,599.00 list · direct from BLUETTI
Prices may vary by retailer and are subject to change.