Head-to-head test
EcoFlow DELTA 3 Ultra vs Anker SOLIX C1000 Gen 2
Every argument on paper goes to the DELTA 3 Ultra, and then you try to lift 72.1 lb: the only question that settles this page is whether the thing ever has to leave the room you put it in.
Full profiles: EcoFlow DELTA 3 Ultra → · Anker SOLIX C1000 Gen 2 →
Looking for a different matchup? EcoFlow DELTA 3 vs Anker SOLIX C1000 Gen 2
Written by Gunner GustafsonUpdated
Whole-Home Backup Tester, Station Arena Test Desk
$1,399.00 · direct from EcoFlow
Last checked 3 days ago. Prices move — check before you buy.
$529.99 · direct from Anker
Last checked 3 days ago. Prices move — check before you buy.
Spec deltas
Three times the energy for $749 more. The DELTA 3 Ultra holds 3,072Wh against the SOLIX C1000 Gen 2's 1,024Wh, and the capacity you add to get there is the cheapest capacity on this page: less per watt-hour than the watt-hours already sitting inside either box. As a question about stored energy, this comparison is over in the first paragraph.
Then you try to move it. 72.1 lb is a bent-knees, both-hands, don't-do-it-on-the-stairs lift, and it doesn't get lighter the second time. The Anker goes from the hatchback to the picnic table in one hand with a coffee in the other. One of these you position. The other you carry.
Everything else ties. Same 4,000 cycles, same five years, same 10ms switchover, so nothing plugged into either one notices the grid go down. Neither covers the 4,685Wh van-life day further down. What's actually left to decide is how much energy you need in one place, and how often that place changes.
What the Numbers Reveal
Each conclusion stated first — the numbers behind it on one line, the full analysis below.
weight
So you aren't paying for the extra energy in dollars. You're paying for it in pounds. 72.1 lb against 24.9 lb is 2.9 times the mass (72.1 ÷ 24.9), which is the distance between a one-hand carry and a lift you set your feet for. The money and the muscle point in opposite directions, and only one of them changes depending on where the box lives.
DELTA 3 Ultra: $1,299 for 3,072Wh, $.42 per watt-hourSOLIX C1000 Gen 2: $550 for 1,024Wh, $.54 per watt-hourDELTA 3 Ultra weighs 72.1 lb; SOLIX C1000 Gen 2 weighs 24.9 lb
Why it mattersIf it's going to sit in a garage or an RV bay and stay there, buy the capacity. It's on sale. If it moves more than a few times a year, the weight is the real price and the Anker is the honest answer.
solar input
Next to a wall socket that asymmetry never surfaces: the Anker just refills three times in about two and a half hours of plug time (3 × 49 minutes)B1 and the capacity gap becomes a question of how often you get up off the couch. Off-grid it bites. One overcast morning leaves the Ultra further from full than the smaller unit, because a big battery on a barely bigger charger takes longer to forgive a bad day. Capacity earns its price exactly where there's no wall and no dependable sun, which is the multi-day storm, and earns a lot less on a weekend you drive home from.
DELTA 3 Ultra: 3,072Wh capacity against 800W maximum solar inputSOLIX C1000 Gen 2: 1,024Wh capacity against 600W maximum solar inputReviewers time a full wall recharge of the C1000 Gen 2 at roughly 49 minutes, against 58 to 80 minutes on the platform it replacesB1
Why it mattersBuy the Ultra for the storm. If your worst case ends within reach of an outlet, you're paying for 2,048Wh you'd have had no trouble replacing anyway.
cost / lifetime kWh
Which means these two are priced for two different jobs. $0.11 against $0.13 is an energy price, and it pays out to people who actually move energy: van conversions, jobsites, anyone off-grid on a Tuesday. A backup buyer isn't purchasing kilowatt-hours at all. They're renting readiness by the year, and readiness rents for $260 on the Ultra and $110 on the Anker.
DELTA 3 Ultra: 3,072Wh × 4,000 cycles = 12,288kWh over its life, $0.11 per lifetime kWhSOLIX C1000 Gen 2: 1,024Wh × 4,000 cycles = 4,096kWh over its life, $0.13 per lifetime kWhBoth carry a 5-year warranty: $260 per warranty year for the Ultra, $110 for the C1000 Gen 2
Why it mattersCycle it hard and the Ultra pays you back in energy. Buy it as insurance and you're paying $150 a year ($260 − $110) for capacity that mostly sits at full charge, waiting.
The noise is real. It just lives in a different room. It shows up above roughly 1,000WB2, which is kettles and heaters and fast charging, so it's a Saturday-afternoon problem and not a 3 a.m. one. Choosing the Ultra because it's the quieter unit buys an advantage in a scenario nobody runs at bedtime. What actually decides the night stand is how many nights you get: at 85% usable after inverter losses, 1,024Wh leaves about 870Wh, or roughly two and a half nights at 320Wh, while 3,072Wh leaves about 2,611Wh, or roughly eight.
DELTA 3 Ultra rated at 30 dBA; SOLIX C1000 Gen 2 rated at 35 dBAThe C1000 Gen 2's fans are near-silent under about 200W but measure around 55 dB above 1,000W, the one complaint that recurs across reviewsB2Reviewers running the Ultra's inverter to its maximum output report the fans never become annoying or distractingA1A2The CPAP overnight profile draws 320Wh, 12% of the Ultra's usable capacity and 37% of the C1000 Gen 2's
Why it mattersSize on nights, not decibels. Two nights is the Anker's ceiling and a week is the Ultra's, and that's the only difference in this pair that will actually wake you up.
The specific dimensions that decide these two units — everything else is a tie.
Portability & Form Factor
Selected because: 72.1 lb against 24.9 lb is the one line on the spec sheet that no amount of capacity argues with.
weight
A power station you resent hauling is the one that stays home on the weekend you needed it. The Ultra is a unit you position once and then visit: beside the panel, in the RV bay, on the garage shelf where the extension cords already live. Basement stairs are a project. A truck bed is a two-person job, or a bad idea you get away with.
The Anker comes out of the hatchback, across the grass and onto the table with nobody spotting you. That's why it keeps winning arguments it loses on the spec sheet. The biggest battery in the world supplies zero watt-hours from the garage.
Runtime: Will It Power Your Gear?
Selected because: Four of the six modelled days end early on the SOLIX C1000 Gen 2 and don't on the DELTA 3 Ultra.
continuous output
910Wh is the cruelest number on this page. That's a remote workday, and on the Anker it lands at 105% of usable capacity, short of a full day by about 5%. Close enough that a light Tuesday or a top-up at lunch gets you home. Far enough that you can't plan a week around it.
That 5% is the entire argument for capacity. A unit that finishes your day is a unit you stop thinking about; a unit that comes up short by a rounding error is a chore with a battery inside it. The camping weekend and the eight-hour outage aren't close on the Anker, they're simply over. So run your own numbers. Land anywhere near 1,024Wh and the Ultra isn't luxury, it's the requirement. Land well under, at laptop and CPAP scale, and the extra capacity is ballast you paid for.
Lifetime Value
Selected because: $0.11 per lifetime kWh against $0.13 points one way; $260 against $110 a warranty year points the other.
cost / lifetime kWh
$0.11 a kilowatt-hour against $0.13, and the Ultra is the cheaper unit to own. Both are rated to 4,000 cycles, so capacity does all the dividing: 12,288kWh of lifetime energy on one side, 4,096kWh on the other.
That verdict carries a condition nobody prints on the box. It assumes you actually consume 12,288kWh, and nobody cycles a home-backup unit 4,000 times. If yours will spend its life at full charge watching the weather, you're not buying energy at all. You're buying five years of standing by, and standing by costs more than twice as much on the Ultra. That's the honest reason the cheaper unit can be the better buy while losing every efficiency number on the page.
Growth Path
Selected because: Only one of these takes an expansion battery, and it's the one starting 2,048Wh behind.
solar input
Whatever the DELTA 3 Ultra holds the day it arrives is the last watt-hour it will ever hold. There's no expansion port and no add-on battery. 3,072Wh is the floor and the ceiling at once.
The SOLIX C1000 Gen 2 does take expansion batteries, which reads as the more future-proof purchase right up until you check the starting line. It begins 2,048Wh behind, so the first battery you bolt on is mostly buying back capacity the Ultra shipped with, at whatever the accessory costs. Growth only turns into an advantage past 3,072Wh. Under that line the sealed box gets you there in one purchase. Over it, the Anker is the only one of the two that can follow you.
What the Specs Don't Tell You
Selected because: Weight, a sealed lid, surge headroom, and what five years of warranty actually costs.
Surge decides whether an appliance starts, not how long it runs. A fridge or a well pump yanks a multiple of its rated draw for the half-second the motor spins up, and both of these clear a typical residential fridge on that test. The gap opens on the second motor, when the pump kicks in while the fridge is already cycling and something has to give.
The rest of the cards below are charges against our own pick, and they're fair ones. The weight and the sealed lid are the price of the capacity, not a surprise bolted to it. The warranty ties on coverage and splits on money, which is where a backup buyer should have been looking the whole time.
Strengths & trade-offs
EcoFlow DELTA 3 Ultra
Strengths
- +Larger battery capacity
- +Higher AC output
- +Faster solar charging
Trade-offs
- –Substantially more expensive (+$869) than the SOLIX C1000 Gen 2.
- –Significantly heavier (+47.2 lbs), making it harder to move.
Anker SOLIX C1000 Gen 2
Strengths
- +Costs $869 less
- +Lighter by 47.2 lb
Trade-offs
- –Weaker inverter (-1,600W) limits appliance compatibility.
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
A 2,100Wh weekend leaves the DELTA 3 Ultra at 80% of its usable capacity. It goes out full and comes home nearly empty, with just enough left for the one thing you didn't plan for. The SOLIX C1000 Gen 2 needs 2.4 charges to cover the same trip, so it only works with a hookup at the site or panels riding along. The Ultra wins the weekend on paper, then asks you to load it into the car for every one of them.
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
DELTA 3 Ultra
1,645Wh over eight hours costs the DELTA 3 Ultra 63% of its usable capacity, so the lights come back on with better than a third of the battery still there for the morning. The SOLIX C1000 Gen 2 gets a little over half the night at 189%, then wants a recharge from the grid that's the reason you're reading this. Both switch over in 10ms, so nothing in the house reboots either way. The only question is how deep into the night you get.
Battery budget usedlower = more headroom
LOAD Fridge 150W×8h · Router + Modem 20W×8h · LED Lights (4 bulbs) 40W×6h · Phone Charger 15W×3h
SCN-03 · 8 hours · needs 320Wh
CPAP Overnight
Sleep therapy without interruption — the #1 medical use case
DELTA 3 Ultra
A 320Wh night barely registers on the DELTA 3 Ultra: 12% of usable capacity, or about eight nights on one charge. The SOLIX C1000 Gen 2 spends 37% a night and gets you roughly two and a half. Both are silent at this load, so this isn't a noise decision at all. It's a question of how long your power actually stays out, and if two nights covers every outage you've had, that's the cheaper answer.
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
DELTA 3 Ultra
910Wh puts the SOLIX C1000 Gen 2 at 105% of its usable capacity. It misses a full workday by the width of a rounding error, which is worse than missing by a lot: close enough to attempt, not close enough to trust, so you spend the afternoon doing mental math instead of work. The DELTA 3 Ultra spends 35% and never raises the subject.
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
Both handle game day; the DELTA 3 Ultra keeps more in reserve (26% used vs 77%). Tailgating is a light load, though, so the number you'll feel is weight: 24.9 lbs for the SOLIX C1000 Gen 2 against 72.1 lbs for the DELTA 3 Ultra, from the trunk to the setup spot.
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 finishes this day. 4,685Wh is 179% of the DELTA 3 Ultra's usable capacity and 538% of the SOLIX C1000 Gen 2's, which is a polite way of saying a full-time van load wants a wired 12V house bank with alternator charging, not a portable. If you're set on one of these two, the SOLIX C1000 Gen 2 is the only one that takes expansion batteries. Reaching a 4,685Wh day from a 1,024Wh base takes several of them, and costs more than the problem does.
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: DELTA 3 Ultra runs 12.7h vs 4.2h.
$1,399 list · direct from EcoFlow
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 0–174.1hComfort & Convenience
Makes off-grid life actually enjoyablescale 0–34.8hHigh-Draw Appliances
These reveal the real limitsscale 0–2.6h¹ 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
August 2, 2026
Verdict: the DELTA 3 Ultra, on Power Score margin
Buy the DELTA 3 Ultra if it gets a home. The $749 between $1,299 and $550 buys 2,048Wh, which works out to about $0.37 per watt-hour ($749 ÷ 2,048Wh): a bulk discount on the only thing you're actually shopping for, and less than either unit charges for the capacity it arrives with. What that capacity buys is an eight-hour outage you don't have to manage. 1,645Wh takes 63% of the Ultra's usable capacity and 189% of the Anker's, which is a numerical way of saying one of them runs out and the other doesn't. The 3,600W inverter with 7,200W behind it starts motor loads that make a 2,000W/3,000W unit hesitate. Confidence stops at 7 for one reason, and you can feel it in your back: 72.1 lb against 24.9 lb. If this rides to a campsite or a jobsite on any regular schedule, none of that arithmetic survives contact with the tailgate. Take the light one, keep the $749, plug it in more often.
Editor-assigned confidence, based on cited owner research and spec analysis.
List prices as of August 2, 2026. The links below open EcoFlow's and Anker's current prices.
$1,399.00 · direct from EcoFlow
Last checked 3 days ago. Prices move — check before you buy.
or check the SOLIX C1000 Gen 2 price$529.99 list
Written by Gunner Gustafson, Whole-Home Backup Tester · Station Arena Test Desk · Updated August 2, 2026
Measured Data
Benchmark scores and the full spec record, side by side.
Benchmark scores
Not rated for both units (minimum threshold unmet): CPAP, Apartment Balcony, Camping.
Full specifications
ᵈ Derived: price ÷ rated capacity. See the data behind our comparisons →
Comparison ToolAdd more power stations, side by sideOpen Tool →How these numbers are produced
Numeric verification
Every figure on this page traces to our spec database or arithmetic on it — no estimated numbers.
Owner claims
Statements about owner experience are cited to published reviews — see Sources & Research Notes below.
Runtime model
Runtime = (rated capacity × 0.85 inverter efficiency) ÷ device wattage. Solar recharge estimates assume panels deliver 70% of rated output. Cold weather, battery age, and stacked loads reduce real-world results.
Power Score
Computed from 14 published spec dimensions, weighted per use-case bench. Higher is better; a unit must meet a bench's minimum threshold to be rated.
See the full weight table and data sourcing on our methodology page →Class ranking (the star rating)
Each unit's star score is a category ranking, not customer reviews — no buyer opinions feed it. We score every station on size-independent quality (value, output, portability, endurance, ports, warranty, and more), then percentile-rank it against the other units in its capacity class, so a class-leading compact unit and a class-leading whole-home unit can both earn 5★. Here, DELTA 3 Ultra rates 4.6/5 (79th percentile of 25 Large-class units), and SOLIX C1000 Gen 2 rates 4.9/5 (96th percentile of 26 Everyday-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.
DELTA 3 Ultra: 72.1 lb Picks the Room
Bent knees, both hands, flat ground. That's the lift, and it's a different sport from the one-hand carry the SOLIX C1000 Gen 2 asks for. On a shelf beside the breaker panel it costs you nothing at all, ever. In and out of a car it costs you something on every single trip, and the trips are where power stations quietly stop getting used. Decide where this one lives before you decide anything else on the page.
DELTA 3 Ultra: 3,072Wh Is the Floor and the Ceiling
No expansion port, no add-on batteries, no second act. What you buy is what you'll still have in year five. The SOLIX C1000 Gen 2 does take expansion batteries, and that sounds like the more future-proof purchase right until you check the starting line: it begins 2,048Wh behind, so the first battery you bolt on is mostly buying back capacity the Ultra shipped with. Growth is a real advantage past 3,072Wh and a wash below it. This is the single best reason to pause on the pick above, and if you know your needs are about to climb, it's worth taking seriously rather than arguing with.
Surge Headroom: 2.0× Against 1.5×
7,200W of surge over 3,600W continuous gives the DELTA 3 Ultra a 2.0× cushion. The SOLIX C1000 Gen 2's 3,000W over 2,000W gives it 1.5×. That cushion decides whether a compressor starts, not how long it runs: fridges, pumps and air conditioners pull a multiple of their rated draw for the half-second the motor spins up. Both units clear a typical residential fridge. The difference shows up on the second motor, when the pump kicks in while the fridge is already cycling and something has to give.
Five Years Each, Priced Differently
Same five years, same 4,000 cycles, so coverage is a dead heat and you can stop comparing it. What isn't a dead heat is what those five years cost: $260 a year on the DELTA 3 Ultra, $110 on the SOLIX C1000 Gen 2. Weekend use won't come near 4,000 cycles on either unit, which means you aren't really buying cycle life at all. You're buying standby by the year, and one of these charges less than half as much for it.
Full record above — the Test Desk pick is the DELTA 3 Ultra.
Check DELTA 3 Ultra price →or check the SOLIX C1000 Gen 2 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 SOLIX C1000 Gen 2 is cheaper to buy, but the DELTA 3 Ultra is cheaper to own. At $0.11/kWh over its lifetime vs $0.13/kWh, the DELTA 3 Ultra's higher cycle life and capacity make each dollar go further over the years. 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.
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
EcoFlow has the deepest catalog in portable power and the biggest owner community, which is why panels, accessories and secondhand advice are easy to find at 9pm on a Sunday. Support is the coin flip. Some owners get a prepaid label and a replacement; others get long waits and a refurbished unit against a warranty claim. Buying through a retailer with its own return window makes the coin flip stop mattering. The October 2025 DELTA Max 2000 recall belongs on the record, though it concerns a different line.
Anker
Ecosystem
7-8 SOLIX portable power stations across C-series (compact) and F-series (flagship), plus the X1 home energy system
Support
US-based support. Historically known for incredible no-hassle replacements, but recent reports describe AI-driven support agents giving generic responses and complex return logistics for heavy units (hazmat shipping). The Anker brand reputation is still strong, but SOLIX-specific support quality is trending down.
Community
Moderate — active Reddit (r/Anker, r/AnkerSOLIXCommunity) and growing. Benefits from Anker's massive consumer electronics brand awareness.
App experience
Rated 4.5/5 iOS (~1,100 ratings) · 4.3/5 Android
Unique strength
Parent brand trust from Anker's consumer electronics dominance. InfiniPower technology for long cycle life. Strong $/Wh value in the mid-size and larger units — the S2000, F2600 and C1000 are among the better buys per watt-hour in the catalog.
Worth knowing
Anker arrives with consumer-electronics brand trust and a well-earned reputation for value per watt-hour in this size class. The honest caveat is that SOLIX support is trending down from a historically excellent level: scripted responses, awkward hazmat return logistics on heavy units, and firmware updates that have removed features without telling anyone.
Analyst note
Two different bets. EcoFlow gives you a bigger ecosystem to grow into and a bigger room to troubleshoot in, from a brand that's had a recall on another line and gives uneven service. Anker gives you a smaller ecosystem and a stronger parent name, with service owners say isn't what it was. Neither of those should decide this purchase. Buy from somewhere with a real return policy, and let capacity and weight settle it.
Growth path
DELTA 3 Ultra
FIXED CAPACITYFixed at 3,072Wh — a sealed, complete system rather than a starting point. There's no expansion port, so that figure is the ceiling: check it against your longest unplugged stretch before you buy.
Accepts up to 800W of solar. Suitable for a 1-2 panel setup.
Generous port selection supports complex multi-device setups.
SOLIX C1000 Gen 2
EXPANDABLESupports Anker 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 600W of solar. Suitable for a 1-2 panel setup.
Generous port selection supports complex multi-device setups.
Expansion batteries are Anker-specific. You're investing in the Anker ecosystem.
Realistic full solar rechargeat 70% of rated panel output — see methodology
Analyst note
Don't read the SOLIX C1000 Gen 2's expandability as a straight win here: it starts at 1,024Wh, below the DELTA 3 Ultra's 3,072Wh, so a first expansion battery largely buys back capacity the DELTA 3 Ultra already includes. It only pulls ahead if you'd grow past 3,072Wh — short of that, the DELTA 3 Ultra's larger fixed capacity is the simpler value.
What Owners Report
Patterns from published owner reports and long-term reviews — every claim cited to its source below.
EcoFlow DELTA 3 Ultra
Nobody has lived with a DELTA 3 Ultra for a year and written it up. What exists is bench testing by reviewers, so read all of it as directional rather than settledA1A5A9. Within that limit it's consistent. Push the inverter to its maximum output and the fans stay out of the wayA1A2. Pull the wall plug and it behaves like a proper UPS, no dips, no shutdowns, nothing on the desk noticingA5A6. It also refuses to throttle its output down to match whatever the input happens to be, which is a real ceiling on other unitsA4. The build reads as engineered rather than assembled: the shell, the AC cable, and the rear port doors that slide into their own protective slotsA9A15.
Two things worth knowing before they surprise you. Overload it and the 30A port is the one it drops first, which matters if that circuit feeds something you'd rather keepA3. And the display washes out in direct sun badly enough that one reviewer ended up cupping their hands around it to read the screenA11. On sustained draw, a test pulling between 300W and 600W from an AC outlet ran a little over 4.5 hoursA7, and a full eight-hour workday with a laptop, a desktop workstation and monitors finished with 40% still in the tankA8.
“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
Anker SOLIX C1000 Gen 2
The headline on the SOLIX C1000 Gen 2 is speed: a full recharge in roughly 49 minutes, against the 58 to 80 minutes of the platform it replacesB1. Reviewers treat it as the refined version of a 1kWh design that was already popular, and several call it the mid-size unit to beatB4. The output clears a standard 1,500W space heater with room left overB3.
The complaint is the fans, and it's the only one that recurs. Near-silent at low load, around 35 dB under 200W, then audibly working through fast charging or heavy output, measured at roughly 55 dB above 1,000WB2. That's the bill for the 49-minute recharge. Same fans, both jobs. You can have the speed or the quiet, so charge it before bed rather than beside it.
“Fast HyperFlash charging — a full recharge in roughly 49 minutes, noticeably quicker than the original C1000's ~58-80 minutes.”
Sources
thepowerpick.com · macrumors.com · outdoorgearlab.com · technerdo.com · mensjournal.com · powerstationadvisor.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]
- Fast charging and higher output over the original are the standout gains; fan noise under load or fast charging is the top complaint. [SOLIX C1000 Gen 2 · 3 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]
- A3
“One weird thing we noticed was the fact that the unit always seems to shut down the 30A port first when you overload the unit.”
thesolarlab.com — EcoFlow DELTA 3 Ultra Plus Review: The Ultimate DELTA? · 2025-09/10 (approx) · [mixed]
- A4
“Many power stations limit you to the input wattage when outputting power, but this EcoFlow power station does not.”
thesolarlab.com — EcoFlow DELTA 3 Ultra Plus Review: The Ultimate DELTA? · 2025-09/10 (approx) · [positive]
- A5
“Over my career I have become accustomed to APC batteries immediately switching on when there is a power hit or power shut-off, and the EcoFlow Delta 3 Ultra Plus works in the exact same way.”
postperspective.com — Review: EcoFlow Delta 3 Ultra Plus Portable Power Station · 2026-04 · [positive]
- A6
“I didn't experience any shut-offs or dips when I unplugged the EcoFlow from the wall.”
postperspective.com — Review: EcoFlow Delta 3 Ultra Plus Portable Power Station · 2026-04 · [positive]
- A7
“Using Maxon's Cinebench 2026 GPU benchmark, I was pulling between 300W and 600W on one of the AC outputs... the EcoFlow Delta 3 Ultra Plus would last a little over 4.5 hours.”
postperspective.com — Review: EcoFlow Delta 3 Ultra Plus Portable Power Station · 2026-04 · [positive]
- A8
“I was able to work remotely for an eight-hour day with 40% power left, which included running my laptop, desktop workstation and monitors.”
postperspective.com — Review: EcoFlow Delta 3 Ultra Plus Portable Power Station · 2026-04 · [positive]
- A9
“It does not feel cheap or fragile. Everything from the outer shell case to the plastic buttons and the AC cable feels substantial and durable enough to withstand day-to-day wear and tear.”
appleinsider.com — EcoFlow Delta 3 Ultra Plus review: Premium, but solid power · 2025-11-16 · [positive]
- A11
“But, while facing the sun, I had to employ the classic "cup hands cover" maneuver to get a clear look at the screen status.”
appleinsider.com — EcoFlow Delta 3 Ultra Plus review: Premium, but solid power · 2025-11-16 · [negative]
- A15
“I really love how the rear panel doors for the input ports slide into protective slots when in use.”
popsci.com — EcoFlow DELTA 3 portable power station series first impressions · 2025-09-29 · [positive]
- B1
“Fast HyperFlash charging — a full recharge in roughly 49 minutes, noticeably quicker than the original C1000's ~58-80 minutes.”
thepowerpick.com / macrumors.com — Anker SOLIX C1000 Gen 2 review · 2026 · [positive]
- B2
“Fan noise is the single most common complaint — nearly silent at low load (about 35 dB under 200W), but the fans ramp up audibly during fast charging or heavy output, reaching around 55 dB at 1,000W-plus.”
outdoorgearlab.com / technerdo.com — C1000 Gen 2 review · 2026 · [negative]
- B3
“The higher continuous output crosses a useful threshold over the original — enough to run a standard 1,500W space heater with headroom to spare.”
thepowerpick.com / mensjournal.com — C1000 Gen 2 review · 2026 · [positive]
- B4
“Reviewers describe it as a refined, powerful, fast-charging update to a popular 1kWh platform, widely rated the mid-size unit to beat in 2026.”
thepowerpick.com / powerstationadvisor.com — C1000 Gen 2 review · 2026 · [positive]
Research compiled August 2, 2026.
Who Should Buy Which
Buy the DELTA 3 Ultra if you…
- →You're wiring in backup and the unit gets a permanent spot beside the panel. An eight-hour outage ends with the next morning still in the battery, and a box that never moves doesn't care what it weighs.
- →You run motor loads: a well pump, a chest freezer, a window AC that has to restart itself at 2 a.m. Startup surge trips these units far more often than running draw does, and the Ultra has the room for it.
- →You cycle it hard. Van conversions with shore power, jobsites, daily off-grid living. The Ultra's cheaper energy only pays out if you actually push 12,288kWh through it, and this is the person who will.
- →You work off-grid. One reviewer finished a full eight-hour day on it with 40% leftA8, which is the difference between working and watching a battery meter.
Buy the SOLIX C1000 Gen 2 if you…
- →The unit travels. Campsite, tailgate, beach, a friend's garage. One hand on the handle, no plan required.
- →Your worst case ends within reach of an outlet. A roughly 49-minute rechargeB1 means the Anker refills three times in the span of one movie.
- →You'd rather keep the money. It costs less than half as much per warranty year as the Ultra, and that difference stays in your account whether the power goes out or not.
- →You charge devices more than you run appliances. 140W of USB-C against the Ultra's 100W makes the cheaper unit the faster one for the thing most people plug in first.
- →You genuinely don't know yet how much power you'll need. This is the one of the two that takes an expansion battery, so guessing low is fixable. Just go in knowing the first battery you add is mostly catching up to what the Ultra already holds.
If neither fits
If your day looks like 4,685Wh, close this tab cheerfully. That's 179% of the Ultra's usable capacity and 538% of the Anker's, so neither one finishes it, and stacking expansion batteries onto a 1,024Wh base to get there is an expensive route to a job a wired 12V house bank with DC-DC charging off the alternator does better and cheaper. Full-time van dwellers should be shopping wiring, not boxes. If you want a portable anyway, start at the 5kWh class and skip both of these.
The Bottom Line
Take the DELTA 3 Ultra if it gets an address. The watt-hours you add cost less than the watt-hours either box came with, and what they buy is a camping weekend, an eight-hour outage and a workday that end rather than run out. Add the surge room for motor loads and the cheaper energy across its life, and there's no version of the paper argument the Anker wins.
Take the SOLIX C1000 Gen 2 if the thing has to travel, or if what you're really buying is readiness instead of energy. 24.9 lb against 72.1 lb is the one difference no spec sheet compensates for, and standing by costs half as much a year on the Anker. Neither of them is a van's daily driver. But if you've got a spot on the garage shelf and a fridge you'd like to stop thinking about during the next storm, buy the Ultra and put it there.
Frequently Asked Questions
Answers drawn from the spec record and cited owner research.
Is the EcoFlow DELTA 3 Ultra worth $749 more than the Anker SOLIX C1000 Gen 2?
As energy, yes. The $749 buys 2,048Wh, about $0.37 per watt-hour, which undercuts the $.42/Wh and $.54/Wh the two units respectively charge for the capacity they arrive with, and it's cheaper per lifetime kilowatt-hour too, $0.11 against $0.13. The catch isn't money. You're buying 72.1 lb instead of 24.9 lb, and if the thing has to move regularly that trade goes bad fast.
Can the Anker SOLIX C1000 Gen 2 run a fridge through an 8-hour blackout?
It'll start one and run it, but it won't cover the whole outage on a single charge. The 1,645Wh eight-hour profile comes to 189% of its usable capacity, so you get roughly halfway before it needs power a dead grid can't give it. The DELTA 3 Ultra spends 63% of its usable capacity on the same eight hours. Both switch over in 10ms, so the fridge never knows the grid dropped.
How long does the EcoFlow DELTA 3 Ultra take to charge from solar?
About 3.8 hours from empty at its 800W maximum input (3,072Wh ÷ 800W), under sun that cooperates. Real panels rarely hold rated output for long, so budget a good day rather than an afternoon, and size the array to the full 800W the unit will take. The SOLIX C1000 Gen 2 refills 1,024Wh at up to 600W in about 1.7 hours.
Can you add extra batteries to the EcoFlow DELTA 3 Ultra?
No. It's fixed at 3,072Wh with no expansion port, so what you buy is the final number. The SOLIX C1000 Gen 2 is the one here that accepts expansion batteries from its 1,024Wh base, but the first one you add mostly buys back capacity the Ultra already includes. Expansion only pulls ahead if you expect to pass 3,072Wh.
Which one is quieter to sleep next to for CPAP?
At CPAP loads, effectively neither. A CPAP sits well under the 200W where the Anker's fans start working, and it measures about 35 dB there against the Ultra's 30 dBA rating. The gap only opens above about 1,000W, where the Anker reaches around 55 dB while reviewers report the Ultra's fans stay out of the way even at full output. Size on nights instead: a 320Wh night is about two and a half nights on the C1000 Gen 2 and about eight on the Ultra.
Where to buy
EcoFlow DELTA 3 UltraPick
$1,399.00
$1,399.00 · direct from EcoFlow
Last checked 3 days ago. Prices move — check before you buy.
Anker SOLIX C1000 Gen 2
$529.99
$529.99 · direct from Anker
Last checked 3 days ago. Prices move — check before you buy.
Prices may vary by retailer and are subject to change.