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Head-to-head test

EcoFlow DELTA 3 Ultra vs Goal Zero Yeti PRO 4000

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

Full profiles: EcoFlow DELTA 3 Ultra · Goal Zero Yeti PRO 4000

Written by Gunner GustafsonUpdated

Whole-Home Backup Tester, Station Arena Test Desk

Stack these against 100+ rivals
MethodologyReader-supported — we may earn from links (details)
EcoFlow DELTA 3 Ultra Portable Power Station

EcoFlow

DELTA 3 Ultra

3,072Wh3,600W72.1 lb

4,728Power Score · Appliance Class

Check price →

$1,399.00 · direct from EcoFlow

Last checked 1 day ago. Prices move — check before you buy.

Goal Zero Yeti PRO 4000 Portable Power Station

Goal Zero

Yeti PRO 4000

3,994Wh3,600W115.7 lb

4,856Power Score · Appliance Class

Check price →

$3,999.95 · direct from Goal Zero

Last checked 1 day ago. Prices move — check before you buy.

Spec deltas

Capacity
3,072Wh
3,994Wh
Output
3,600W
matched
3,600W
Weight
72.1 lb
115.7 lb
Typical price
$1,399
$4,000
Cost / Wh
$0.46
$1.00
Cycle life
4,000
matched
4,000
Solar input
800W
3,000W
01

The EcoFlow DELTA 3 Ultra and Goal Zero Yeti PRO 4000 compete for the same spot. Similar LiFePO4 capacity, similar price range, different brands behind them. In this matchup, ecosystem, app quality, and warranty reputation matter as much as raw specs. We'd buy the DELTA 3 Ultra.

The Yeti PRO 4000 holds 922Wh more than the DELTA 3 Ultra — about 23 hours on a fridge against 17 — a real but modest edge that shows up mainly on longer outages. For camping, tailgating, or keeping devices charged, both have the headroom, so price, weight, and longevity lead the decision instead.

Pick the DELTA 3 Ultra if your primary use is weekend camping or tailgate party. Go with the Yeti PRO 4000 if you primarily need it for 8-hour blackout. Most buyers stop at the sticker price and miss this: over a full lifespan the DELTA 3 Ultra works out to about $0.11/kWh against the Yeti PRO 4000's $0.25, a gap that compounds in the DELTA 3 Ultra's favor the more you cycle it. 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 3 Ultra

With a massive 3,600W output (and 7,200W surge), the DELTA 3 Ultra can run high-wattage appliances like space heaters, hair dryers, and electric grills without tripping. Weighing in at 72.1 lbs, this is not a unit you want to carry far. It's best suited as a stationary backup or RV companion. A standout feature is the value proposition: at roughly $0.46 per watt-hour, it's one of the most cost-effective options on the market.

Strengths

  • +Costs $2,601 less
  • +Lighter by 43.6 lb

Trade-offs

  • Sealed capacity — the Yeti PRO 4000 can add batteries to grow past 3,072Wh; this one can't.

Goal Zero Yeti PRO 4000

With a massive 3,600W output (and 7,200W surge), the Yeti PRO 4000 can run high-wattage appliances like space heaters, hair dryers, and electric grills without tripping. Weighing in at 115.7 lbs, this is not a unit you want to carry far. It's best suited as a stationary backup or RV companion.

Strengths

  • +Larger battery capacity
  • +Faster solar charging

Trade-offs

  • Substantially more expensive (+$2,601) than the DELTA 3 Ultra.
  • Significantly heavier (+43.6 lbs), making it harder to move.
  • Very heavy unit that may be difficult for one person to lift.
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

DELTA 3 Ultra

The Yeti PRO 4000 at 115.7 lbs is not a take-along — it rolls off a truck bed if it travels at all, so this scenario belongs to the DELTA 3 Ultra by default — and it earns it, covering the 2,100Wh with 511Wh to spare. Capacity was never the Yeti PRO 4000's problem here; getting to a campsite was.

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

Yeti PRO 4000

Both survive the night. The Yeti PRO 4000 finishes at 48% used with 1,750Wh left — 1.1 more nights like it. The DELTA 3 Ultra finishes at 63% with 966Wh, 59% of a second night. If your outages tend to run past one evening, that difference is the whole argument between them.

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 with room to spare and capacity decides nothing. Fan noise would — but Yeti PRO 4000 doesn't publish a figure, so there's nothing to hold it to. Buy on price, weight, and whether you can live with a fan you haven't heard.

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

Either unit

Both power your workstation all day without strain. At these utilization levels the real difference is USB-C for direct laptop charging — 140W on the DELTA 3 Ultra against 100W — which beats the inverter for convenience and wastes less energy.

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 Yeti PRO 4000 at 115.7 lbs is not a take-along — it rolls off a truck bed if it travels at all, so this scenario belongs to the DELTA 3 Ultra by default — and it earns it, covering the 670Wh with 1,941Wh to spare. Capacity was never the Yeti PRO 4000's problem here; getting to a tailgate was.

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 3 Ultra comes up 2,074Wh short (about 56% covered), the Yeti PRO 4000 1,290Wh (72%). Either gets you most of the way, so this is a scenario you plan around rather than one you should rule them out for.

RV & van-life power guide

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 3 Ultra12.7h
63% of usable battery in 8h
Yeti PRO 400016.6h
48% of usable battery in 8h

For this load: Yeti PRO 4000 runs 16.6h vs 12.7h.

Check Yeti PRO 4000 price →

$3,999.95 list · direct from Goal Zero

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 0–226.3h
ApplianceDELTA 3 UltraYeti PRO 4000
CPAP Machine40W draw
DELTA 3 Ultra: 65.3h8 full nights
Yeti PRO 4000: 84.9h10 full nights
Phone Charger15W draw
DELTA 3 Ultra: 174.1h
Yeti PRO 4000: 226.3h
Router + Modem20W draw
DELTA 3 Ultra: 130.6h
Yeti PRO 4000: 169.7h
Starlink75W draw
DELTA 3 Ultra: 34.8h
Yeti PRO 4000: 45.3h
LED Lights (4 bulbs)40W draw
DELTA 3 Ultra: 65.3h
Yeti PRO 4000: 84.9h
Laptop (Working)60W draw
DELTA 3 Ultra: 43.5h
Yeti PRO 4000: 56.6h

Comfort & Convenience

Makes off-grid life actually enjoyablescale 0–45.3h
ApplianceDELTA 3 UltraYeti PRO 4000
Box Fan75W draw
DELTA 3 Ultra: 34.8h
Yeti PRO 4000: 45.3h
LED TV (55")80W draw
DELTA 3 Ultra: 32.6h
Yeti PRO 4000: 42.4h
Mini-Fridge150W draw
DELTA 3 Ultra: 17.4h
Yeti PRO 4000: 22.6h
Electric Blanket200W draw
DELTA 3 Ultra: 13.1h1 full night
Yeti PRO 4000: 17h2 full nights

High-Draw Appliances

These reveal the real limitsscale 0–3.4h
ApplianceDELTA 3 UltraYeti PRO 4000
Coffee Maker1000W draw
DELTA 3 Ultra: 2.6h
Yeti PRO 4000: 3.4h
Microwave1200W draw
DELTA 3 Ultra: 2.2h
Yeti PRO 4000: 2.8h
Space Heater1500W draw
DELTA 3 Ultra: 1.7h
Yeti PRO 4000: 2.3h

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: the DELTA 3 Ultra

The DELTA 3 Ultra wins this on price rather than on paper — it gives up 922Wh less capacity to the Yeti PRO 4000. At $2,601 less and 43.6 lbs lighter, it is the better buy of the two.

Cost to ownDELTA 3 Ultra$0.11 vs $0.25 /lifetime-kWh
Typical priceDELTA 3 Ultra$1,399 vs $4,000
PortabilityDELTA 3 Ultra72.1 vs 115.7 lb
Solar inputYeti PRO 40003,000W vs 800W
ExpansionYeti PRO 4000expandable vs closed system

Overall score margin: 4,728 vs 4,856 (−2.7%)

List prices as of July 10, 2026. The links below open EcoFlow's and Goal Zero's current prices.

Check DELTA 3 Ultra price

$1,399.00 · direct from EcoFlow

Last checked 1 day ago. Prices move — check before you buy.

or check the Yeti PRO 4000 price$3,999.95 list

Written by Gunner Gustafson, Whole-Home Backup Tester · Station Arena Test Desk · Updated July 10, 2026

04

Measured Data

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

Benchmark scores

DELTA 3 UltraYeti PRO 4000
Overall Power Score
4,728
4,856
RV LivingEnergy Density & Output
4,360
4,956
Home BackupCapacity & Resilience
4,810
4,985
Solar GeneratorSolar Input & Efficiency
3,792
4,597
Food TruckSustained Heavy Output
4,365
4,830

Not rated for both units (minimum threshold unmet): UPS, Tailgating.

Full specifications

DELTA 3 Ultra
$1,399★ our pick
See live price →
Yeti PRO 4000
$3,999.95
See live price →
Capacity (Wh)
3072
3994
Output (W)
3600
3600
Surge Peak
7200W
7200W
AC Outlets
6
4
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 3 Ultra rates 4.7/5 (80th percentile of 26 Large-class units), and Yeti PRO 4000 rates 3.6/5 (20th 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.

[CAUTION]

Weight Reality Check

Neither unit is grab-and-go. The DELTA 3 Ultra (72.1 lbs) is manageable solo but heavier than a large checked suitcase. The Yeti PRO 4000 (115.7 lbs) is firmly a two-person lift. It goes where you put it and stays there. That's a 44 lb difference, and it is paid once — getting the heavier one into position, not every time you move it.

[NOTE]

DELTA 3 Ultra: Fixed Capacity

The DELTA 3 Ultra is sealed at 3,072Wh — fine if that covers you, but it's the ceiling. By contrast the Yeti PRO 4000 can add expansion batteries, though the first thing it has over the DELTA 3 Ultra is its own 3,994Wh base — expansion is the step after that, for the buyer who would outgrow 3,994Wh as well.

[NOTE]

UPS Switchover: ≤10ms vs ≤15ms

Both list a UPS mode, at different rated speeds. The DELTA 3 Ultra is rated ≤10ms — quick enough on paper that desktop PCs and routers should ride through, treating that as the rating it is. The Yeti PRO 4000 is rated ≤15ms — fine on paper for routers and most electronics; the fussiest PC power supplies sit right at this line. If a computer with unsaved work is the thing being protected, the stated class is worth the attention; nothing here is a lab result.

[NOTE]

Warranty: No Difference

Both units carry the same 5-year warranty, so coverage isn't a tiebreaker here. 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 Yeti PRO 4000's 1.3, but that spread is the price gap, not the terms.

[NOTE]

Yeti PRO 4000: Noise Level Not Disclosed

The DELTA 3 Ultra publishes its noise level (30dB); the Yeti PRO 4000 doesn't publish one. That isn't evidence the Yeti PRO 4000 is louder — it means there's no figure to hold it to, and no way to compare the two on this without hearing them. If you're buying for a bedroom, a CPAP, or an apartment, treat the DELTA 3 Ultra's 30dB as the only published number on the table — a spec-sheet figure, not a measurement — and look for hands-on reports of the Yeti PRO 4000 before deciding.

Full record above — the Test Desk pick is the DELTA 3 Ultra.

Check DELTA 3 Ultra price →or check the Yeti PRO 4000 price
05

Ownership Analysis

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

Lifetime value

DELTA 3 UltraYeti PRO 4000

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

DELTA 3 Ultra
Yeti PRO 4000
Purchase price
$1,399.00
$3,999.95
Lifetime energy delivered
12,288 kWh
15,976 kWh
Cost per lifetime kWh
$0.11
$0.25
Cost per warranty year
$280/yr
$800/yr
Battery lifespan
11yr daily · 38.5yr weekend · 76.9yr weekly
11yr daily · 38.5yr weekend · 76.9yr weekly

Analyst note

The DELTA 3 Ultra wins on both sticker price and long-term value. At $0.11/kWh over its lifetime, it's meaningfully cheaper to own. Clear value winner. One thing to know reading the table: both carry the same 4,000-cycle rating, so the lifetime rows are sticker price and capacity in disguise — the wear horizon is identical and decides nothing here.

Delivers each lifetime kWh for $0.14 less — check the DELTA 3 Ultra 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 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

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 →

Goal Zero

Ecosystem

Focused — a compact current line (6th-gen Yeti and Yeti Pro series), the previous-gen X series now out of stock across every model on Goal Zero's own store (checked 2026-09-13: 200X, 500X, 1000X, 1500X, 3000X, 6000X, some listed only as open-box), so buying one new means finding retailer stock, Sherpa power banks for the under-100Wh tier, plus Alta coolers, Nomad/Ranger solar panels, and vehicle integration kits

Support

US-based company (Salt Lake City, owned by NRG Energy). Historically considered premium support, but 2025-2026 reports describe long wait times, unresponsive email communication, and tickets going unaddressed for weeks. The "premium support justifies premium pricing" argument is weakening.

Community

Small but loyal — strong following in overlanding and preparedness communities. Official community forums were recently shuttered, frustrating long-time users.

App experience

Rated 4.4/5 iOS (~1,200 ratings) but recent reviews skew negative — recurring connectivity issues, crashes, and stability problems.

Unique strength

Pioneer of the portable power market — strongest brand heritage. US-based company with ruggedized, weather-resistant designs (IP ratings vary by model). Integrated "Yeti-Ready" ecosystem with coolers, lights, and vehicle kits.

Worth knowing

Typically the priciest brand per watt-hour — though individual pairings vary, and on some pages the Yeti is the cheaper energy. Support quality has declined from its "premium" standard. Perceived as competitively stagnant vs. faster-innovating Chinese competitors. Reliability reports on newer models are concerning.

All Goal Zero power stations tested →

Analyst note

EcoFlow and Goal Zero are close competitors. Both have established support channels and growing ecosystems. Compare their specific warranty terms and community size for your peace of mind.

Growth path

DELTA 3 Ultra

FIXED CAPACITY

Fixed 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.

Yeti PRO 4000

EXPANDABLE

Supports Goal Zero expansion batteries, so you can add capacity later without replacing the base unit — useful if your needs may climb past 3,994Wh.

Accepts up to 3,000W of solar. Enough for a serious multi-panel array.

Generous port selection supports complex multi-device setups.

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

DELTA 3 UltraYeti PRO 4000

Analyst note

The DELTA 3 Ultra is sealed at 3,072Wh, which is fine if that covers you. The Yeti PRO 4000 starts at 3,994Wh and can grow beyond it with Goal Zero expansion batteries — real headroom the DELTA 3 Ultra doesn't have if your needs climb toward partial-home backup.

06

The Bottom Line

The full picture comes down to this. The DELTA 3 Ultra 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 Yeti PRO 4000 wins in the scenarios that match your life, it's the right choice regardless of aggregate scores.

If neither the DELTA 3 Ultra nor the Yeti PRO 4000 feels like the right fit, your power needs probably sit outside what these two target. For lighter use — weekend camping or phone/laptop charging — you'd be overpaying for capacity you'll rarely tap. Consider a unit in the 500–1,500Wh range instead. Prices on portable power stations fluctuate frequently. Both EcoFlow and Goal Zero 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.

Is the Yeti PRO 4000 worth $2,601 more than the DELTA 3 Ultra?

The short answer: yes, if you'll actually use the extra capability. The Yeti PRO 4000 costs $2,601 more, but that premium buys you 922Wh more battery capacity (that's 5 extra hours of running a mini-fridge); 2,200W faster solar charging for quicker off-grid recovery. On a cost-per-watt-hour basis, you're paying $1.00/Wh vs $0.46/Wh. For regular use, we'd pay the premium.

How does the 922Wh capacity difference actually affect daily use?

The Yeti PRO 4000's 3,994Wh battery keeps a mini-fridge running for roughly 23 hours vs the DELTA 3 Ultra's 17 hours. Both can handle a full 8-hour blackout setup (fridge + router + lights + phone charging ≈ 1,645Wh), but the Yeti PRO 4000 finishes with significantly more margin. That matters if conditions aren't ideal or the outage runs long. What specs don't mention: runtime drops 20-30% in cold weather (below 32°F/0°C) as battery chemistry slows down. The Yeti PRO 4000'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 Yeti PRO 4000, or is the DELTA 3 Ultra the only portable option?

Neither is "portable" in any hiking sense. The DELTA 3 Ultra (72.1 lbs) and the Yeti PRO 4000 (115.7 lbs) are both appliances you place and leave. The 43.6-lb difference matters when loading into a vehicle or moving between rooms, but that's about it. If true portability is your priority, look at units under 20 lbs in a different class entirely.

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

On paper, the Yeti PRO 4000 accepts 3,000W vs the DELTA 3 Ultra's 800W 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 1.9 hours for the Yeti PRO 4000 and 5.5 hours for the DELTA 3 Ultra. That gap widens on cloudy days, when the Yeti PRO 4000'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 Yeti PRO 4000's advantage is substantial.

What if I need more capacity than the DELTA 3 Ultra's 3,072Wh later?

The DELTA 3 Ultra is sealed at 3,072Wh, so if you expect your needs to climb, the Yeti PRO 4000 is the more future-proof pick: it starts at 3,994Wh and adds Goal Zero-compatible batteries without replacing the base unit. That said, "not expandable" isn't a flaw on its own — if 3,072Wh comfortably covers your loads, the DELTA 3 Ultra is a complete unit, not a downgrade.

Is EcoFlow or Goal Zero more reliable for long-term ownership?

Both brands have strengths and trade-offs. EcoFlow: Mixed. 2-5 years depending on model (DELTA Pro Ultra line gets 10 years). Some users report smooth claims; others report runarounds. Register your product to extend coverage. Goal Zero: 5 years on LFP models, 2 years on older NMC models. Battery must be charged within 7 days of purchase and every 6 months to maintain warranty (strict). Product reliability concerns have increased — repeat "Battery Fault" errors reported even on newer Yeti Pro 4000. 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 3 Ultra or the Yeti PRO 4000?

We'd buy the DELTA 3 Ultra. Strong value at a lower price, and for most real-world use cases the spec gaps don't translate to meaningful capability gaps. The Yeti PRO 4000 makes sense only if you specifically need its higher capacity for demanding sustained loads like full-home backup or commercial use.

Check DELTA 3 Ultra price →

Where to buy

DELTA 3 Ultra

EcoFlow DELTA 3 UltraPick

$1,399.00

Check current price

$1,399.00 · direct from EcoFlow

Last checked 1 day ago. Prices move — check before you buy.

Yeti PRO 4000

Goal Zero Yeti PRO 4000

$3,999.95

Check current price

$3,999.95 · direct from Goal Zero

Last checked 1 day ago. Prices move — check before you buy.

Prices may vary by retailer and are subject to change.