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Head-to-head test

EcoFlow DELTA 2 vs BLUETTI AC50B

Real-world runtimes, scenario verdicts, and ownership costs compared — which wins for your use case.

Full profiles: EcoFlow DELTA 2 → · BLUETTI AC50B →

Written by Ian SchneiderUpdated

Solar & Off-Grid Tester, Station Arena Test Desk

Stack these against 100+ rivals
MethodologyReader-supported — we may earn from links (details)

Spec deltas

Capacity
1,024Wh
448Wh
Output
1,800W
700W
Weight
27 lb
14.8 lb
Typical price
No longer sold
$399
Cost / Wh
—
$0.89
Cycle life
3,000
matched
3,000
Solar input
500W
200W
01

The EcoFlow DELTA 2 (1,024Wh) and BLUETTI AC50B (448Wh) sit in different weight classes. The real question: do your power needs justify the larger unit, or would you be overpaying for capacity that sits unused? The DELTA 2 has a slight edge, but the margin is close enough that your use case should break the tie.

What the spec gap means in practice: the DELTA 2's 1,800W inverter has the headroom for a window AC, a full-size fridge, and power tools. The AC50B's 700W inverter can't run the heaviest of those — a window AC or a high-surge power tool needs more than it can hold, and it publishes no surge headroom above that rating. On stamina, the DELTA 2 keeps a fridge alive for roughly 6 hours vs the AC50B's 3 hours.

Pick the DELTA 2 if your primary use is tailgate party. Go with the AC50B if its specific strengths below line up better with your use. Keep scrolling for the full breakdown. The scenario verdicts below hold a few surprises.

02

Bench Notes

What each unit does well, where it falls short, and the trade-offs that matter.

EcoFlow DELTA 2

The 1,800W inverter handles most daily devices like laptops, blenders, and TVs, but will struggle with heating elements that require over 1500W.

Strengths

  • +Larger battery capacity
  • +Higher AC output
  • +Faster solar charging

Trade-offs

  • –Significantly heavier (+12.2 lbs), making it harder to move.

BLUETTI AC50B

At 700W, this unit is strictly for personal electronics (phones, laptops) and small CPAP machines. Do not expect to run kitchen appliances. At only 14.8 lbs, it is exceptionally portable. You can easily carry it one-handed to a campsite or tailgating party.

Strengths

  • +Lighter by 12.2 lb

Trade-offs

  • –Weaker inverter (-1,100W) limits appliance compatibility.
  • –Sealed capacity — the DELTA 2 can add batteries to grow past 448Wh; this one can't.
03

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 unit covers this scenario's 2,100Wh: the DELTA 2 comes up 1,230Wh short (about 41% covered), the AC50B 1,719Wh (18%). This is well outside what either unit is for; the right answer here is a larger station, not a choice between these two.

Camping power station guide →

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

Neither unit

Neither unit covers this scenario's 1,645Wh: the DELTA 2 comes up 775Wh short (about 53% covered), the AC50B 1,264Wh (23%). This is well outside what either unit is for; the right answer here is a larger station, not a choice between these two.

Emergency blackout power guide →

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

A CPAP is about 40W for eight hours, so both cover the night, though not twice: the AC50B gets through it with 61Wh to spare. The only published difference is fan noise, and it can't settle this: the AC50B is rated 45dB and the DELTA 2 50dB, but they are two makers' figures, each measured its own way. Neither settles which box is quieter at a bedside. Only the AC50B is still sold, so a new purchase here is just the AC50B; the DELTA 2 is a used-market question.

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

Neither unit

This scenario needs 910Wh and neither unit quite finishes it. The DELTA 2 lands within 5% of it — close enough that trimming one appliance, or accepting a shorter evening, gets you there on the day.

UPS & desk backup guide →

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 2

The AC50B doesn't finish — 381Wh usable against the 670Wh this needs leaves it 289Wh short, about 57% of the scenario covered. The DELTA 2 covers it with 200Wh to spare.

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

Neither unit

Neither unit covers this scenario's 4,685Wh: the DELTA 2 comes up 3,815Wh short (about 19% covered), the AC50B 4,304Wh (8%). This is well outside what either unit is for; the right answer here is a larger station, not a choice between these two.

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

DELTA 24.2h
dead in 4.2h — before your 8h window ends
AC50B1.9h
dead in 1.9h — before your 8h window ends

For this load: DELTA 2 runs 4.2h vs 1.9h.

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 0–58h
ApplianceDELTA 2AC50B
CPAP Machine40W draw
DELTA 2: 21.8h2 full nights
AC50B: 9.5h1 full night
Phone Charger15W draw
DELTA 2: 58h
AC50B: 25.4h
Router + Modem20W draw
DELTA 2: 43.5h
AC50B: 19h
Starlink75W draw
DELTA 2: 11.6h
AC50B: 5.1h
LED Lights (4 bulbs)40W draw
DELTA 2: 21.8h
AC50B: 9.5h
Laptop (Working)60W draw
DELTA 2: 14.5h
AC50B: 6.3h

Comfort & Convenience

Makes off-grid life actually enjoyablescale 0–11.6h
ApplianceDELTA 2AC50B
Box Fan75W draw
DELTA 2: 11.6h
AC50B: 5.1h
LED TV (55")80W draw
DELTA 2: 10.9h
AC50B: 4.8h
Mini-Fridge150W draw
DELTA 2: 5.8h
AC50B: 2.5h
Electric Blanket200W draw
DELTA 2: 4.4h0 full nights
AC50B: 1.9h0 full nights

High-Draw Appliances

These reveal the real limitsscale 0–0.9h
ApplianceDELTA 2AC50B
Coffee Maker1000W draw
DELTA 2: 0.9h
AC50B: — exceeds output
Microwave1200W draw
DELTA 2: 0.7h
AC50B: — exceeds output
Space Heater1500W draw
DELTA 2: 0.6h
AC50B: — exceeds output

¹ 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 10, 2026

Verdict withdrawn: the DELTA 2 is no longer sold

We picked the DELTA 2, but it's been discontinued (EcoFlow now points buyers to the DELTA 3). The AC50B is still on sale, but that alone doesn't make it our pick. The comparison below is still accurate if you own either one.

Overall score margin: 2,994 vs 1,718 (+74.3%)

Written by Ian Schneider, Solar & Off-Grid Tester · Station Arena Test Desk · Updated July 10, 2026

Black Friday · 26 days out

Price to beat:AC50B $279

The lowest we have recorded. A Black Friday price above it is a sale this unit has already had.

Black Friday deals →
04

Measured Data

Benchmark scores and the full spec record, side by side.

Benchmark scores

DELTA 2AC50B
Overall Power Score
2,994
1,718
UPSResponse & Reliability
2,718
1,944
CPAPSleep Therapy Reliability
2,721
2,227
Solar GeneratorSolar Input & Efficiency
2,684
1,597
TailgatingOutlets & Portability
2,936
1,762
Apartment BalconyCompact Solar Living
2,814
1,845
CampingLightweight & Versatile
2,627
1,733

Not rated for both units (minimum threshold unmet): RV Living, Home Backup, Food Truck.

Full specifications

DELTA 2
No longer sold
Capacity (Wh)
1024
448
Output (W)
1800
700
Surge Peak
2700W
N/A
AC Outlets
6
2
240V Outlets
0
0
30A RV Outlets
0
0

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.

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 2 rates 4.1/5 (50th percentile of 27 Everyday-class units), and AC50B rates 4.6/5 (79th percentile of 25 Personal-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.

[NOTE]

Fan Noise: Two Published Ratings

The AC50B is rated 45dB (like a running refrigerator), the DELTA 2 50dB (like moderate rainfall). Neither is a measurement on a shared bench — they are two makers' figures, each measured its own way, so a low number and a high one can describe the same machine at different moments. Take the pair as a prompt to find hands-on reports rather than as a gap you can act on. For most people, fan noise around 45dB and up is where sleep starts to suffer, and neither figure tells you what either unit does at a 40W draw.

[NOTE]

AC50B: Fixed Capacity

The AC50B is sealed at 448Wh, and that is the ceiling. Normally the counterpoint would be that the DELTA 2 can add expansion batteries, but that isn't a live option here: the DELTA 2 is no longer sold, and EcoFlow points owners to the DELTA 3. For a new purchase the expansion question doesn't arise between these two, so the AC50B's fixed 448Wh is simply what you get.

[NOTE]

AC50B: Power Lifting to 1,000W

The AC50B has BLUETTI's Power Lifting mode, which runs a resistive appliance rated up to 1,000W from its 700W 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 448Wh 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 2 publishes no equivalent.

[NOTE]

Warranty: No Difference

Both units carry the same 5-year warranty, so coverage isn't a tiebreaker here. The AC50B'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.

05

Ownership Analysis

What happens after you buy — true cost of ownership, brand trust, and growth potential.

Lifetime value

DELTA 2AC50B

│ warranty ends · Reaching the cycle rating means ~80% capacity remains — degraded, not dead.

DELTA 2
AC50B
Purchase price
No longer sold
$399.00
Lifetime energy delivered
3,072 kWh
1,344 kWh
Cost per lifetime kWh
—
$0.30
Cost per warranty year
—
$80/yr
Battery lifespan
8.2yr daily · 28.8yr weekends · 57.7yr weekly
8.2yr daily · 28.8yr weekends · 57.7yr weekly

Analyst note

The DELTA 2 is no longer sold, so there is no price to work its cost per kWh from, and this comparison doesn't quote one. On what you can actually buy today, the AC50B works out at $0.30/kWh over its rated life. If you already own the DELTA 2, the hardware comparison still holds: over its rated life the DELTA 2 delivers about 3,072 kWh and the AC50B about 1,344 kWh. One thing to know reading the table: both carry the same 3,000-cycle rating, so the lifetime rows are sticker price and capacity in disguise — the wear horizon is identical and decides nothing here.

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.

All EcoFlow power stations tested →

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.

All BLUETTI power stations tested →

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 2

EXPANDABLE

Supports EcoFlow expansion batteries, so you can add capacity later without replacing the base unit — useful if your needs may climb past 1,024Wh.

Accepts up to 500W of solar. Suitable for a 1-2 panel setup.

Generous port selection supports complex multi-device setups.

Expansion batteries are EcoFlow-specific. You're investing in the EcoFlow ecosystem.

AC50B

FIXED CAPACITY

Fixed at 448Wh, with no expansion — so size it for your needs up front rather than planning to add capacity later.

Accepts up to 200W of solar. Limited to a single portable panel.

Limited ports. You'll likely need a power strip or splitter.

DELTA 2AC50B

Analyst note

Growth only counts if you can still buy in, and the DELTA 2 is no longer sold (EcoFlow points owners to the DELTA 3). That leaves the AC50B: it is sealed at 448Wh, so buy the size that covers you now. The DELTA 2's expandability still matters if you already own one, but it isn't a reason to pick it over the AC50B.

06

The Bottom Line

The full picture comes down to this. The DELTA 2 edges ahead on our overall analysis, but the margin is narrow enough that your specific use case should drive the decision. Review the scenario verdicts above — if the AC50B wins in the scenarios that match your life, it's the right choice regardless of aggregate scores.

If neither the DELTA 2 nor the AC50B feels like the right fit, your power needs probably sit outside what these two target. If you're planning whole-home backup or running power-hungry appliances (electric heaters, window AC), you'll want a larger system in the 3,000–5,000Wh range with expansion battery support. Prices on portable power stations fluctuate frequently. Both EcoFlow and BLUETTI discount regularly, so check the current price before committing. Prime Day and Black Friday pricing typically drops 20-30%.

07

Frequently Asked Questions

Answers drawn from the spec record and cited owner research.

How does the 576Wh capacity difference actually affect daily use?

The DELTA 2's 1,024Wh battery keeps a mini-fridge running for roughly 6 hours vs the AC50B's 3 hours. What specs don't mention: runtime drops 20-30% in cold weather (below 32°F/0°C) as battery chemistry slows down. The DELTA 2's extra capacity provides a critical cold-weather buffer. For occasional phone and laptop charging, both are overkill. This gap only matters for sustained, multi-appliance use.

Can I actually carry the DELTA 2, or is the AC50B the only portable option?

The AC50B at 14.8 lbs is genuinely grab-and-go. Toss it in a backpack, carry it one-handed to a picnic, take it on a boat. The DELTA 2 at 27 lbs is a different story. It's like carrying a large suitcase full of books. If you're setting up and breaking down camp frequently, this weight difference will exhaust you by day two.

How fast can each unit recharge from solar panels in real conditions?

On paper, the DELTA 2 accepts 500W vs the AC50B's 200W of solar input. What the spec sheet won't tell you: solar panels typically deliver only 60-80% of their rated output due to panel angle, cloud cover, and temperature. In realistic conditions, expect full recharge in about 2.9 hours for the DELTA 2 and 3.2 hours for the AC50B. That gap widens on cloudy days, when the DELTA 2's higher input ceiling captures more of whatever sunlight is available. One more thing: summer gives you ~7 productive solar hours per day. Winter drops to ~4. If solar is your primary recharge method, the DELTA 2's advantage is substantial.

What if I need more capacity than the AC50B's 448Wh later?

The AC50B is sealed at 448Wh, so if you expect your needs to climb, the DELTA 2 is the more future-proof pick: it starts at 1,024Wh and adds EcoFlow-compatible batteries without replacing the base unit. That said, "not expandable" isn't a flaw on its own — if 448Wh comfortably covers your loads, the AC50B is a complete unit, not a downgrade.

Is EcoFlow or BLUETTI more reliable for long-term ownership?

Both brands have strengths and trade-offs. EcoFlow: Mixed. 2-5 years depending on model. Some users report smooth claims; others report runarounds. Register your product to extend coverage. BLUETTI: 2-6 years depending on model (up to 10 years on home backup systems). Response times vary significantly. Some reports of units being deemed unrepairable with no parts available for older models. One piece of advice from the power station community: regardless of brand, buy from Costco or Amazon. Their return policies provide a safety net that manufacturer warranties alone can't match, especially for a product you'll rely on in emergencies. Both brands use LFP (lithium iron phosphate) batteries in their current lineup, the most proven chemistry for longevity and safety.

Bottom line: should I buy the DELTA 2 or the AC50B?

We'd have said the DELTA 2, but it is no longer sold. The AC50B is still on sale, but that alone doesn't make it our pick. The comparison on this page is still accurate if you own either one.

Where to buy

DELTA 2

EcoFlow DELTA 2

No longer sold

AC50B

BLUETTI AC50B

$399.00

Check current price

$399.00 · direct from BLUETTI

Last checked 28 days ago. Prices move — check before you buy.

Prices may vary by retailer and are subject to change.

No longer soldDELTA 2