Head-to-head test
BLUETTI AC300 + 4×B300 vs BLUETTI AC500 + 2×B300K
BLUETTI AC300 + 4×B300 vs BLUETTI AC500 + 2×B300K: Buy the AC300 + 4×B300 for the job most people buy this class to do: store energy.
Full profiles: BLUETTI AC300 + 4×B300 → · BLUETTI AC500 + 2×B300K →
Written by Gunner GustafsonUpdated
Whole-Home Backup Tester, Station Arena Test Desk
Spec deltas
Buy the AC300 + 4×B300 unless a single one of your appliances draws more than 3,000 watts. It holds 12,288Wh to the AC500 stack's 5,530, more than double the reserve, and it stores that energy cheaper, at $0.13 per lifetime kilowatt-hour against $0.20. For $1,648 more you get 6,758Wh more battery; per watt-hour, the bigger stack is the cheaper one, not the splurge.
The catch is real, and it lives at the end of the unit's life rather than the start. The AC300 launched in 2021A0 and BLUETTI has since discontinued itA10, and one owner whose head unit died was told there are no parts left to fix itA9A10. Both stacks use the same 3,500-cycle cells, so the value math holds if the electronics live. But you are buying a discontinued box, and that belongs in the decision.
The AC500 stack answers with the one thing it does better: a 5,000W inverter against 3,000W, with 10,000W of surge. In every scenario a normal home hands these — fridge, CPAP, laptops, a blackout's worth of essentials — 3,000W never runs short. But if your list includes an electric range element, a big well pump, or several heavy loads at once, that headroom is the whole reason to pay less for less battery.
What the Numbers Reveal
Each conclusion stated first — the numbers behind it on one line, the full analysis below.
cost / lifetime kWh
You are not paying a premium for the AC300 stack's extra 6,758Wh. The bigger stack's energy is simply cheaper, up front and over its life, which inverts the usual intuition that more battery costs more per unit.
AC300 stack: 12,288Wh at $5,596AC500 stack: 5,530Wh at $3,948cost per lifetime kWh $0.13 vs $0.20, both rated 3,500 cyclesup-front cost per Wh $0.46 vs $0.71
Why it mattersIf you came to this class to store energy — outages, off-grid, long days between charges — the AC300 stack is both the bigger reserve and the cheaper one, and that settles it.
continuous output
That 5,000W only earns its keep above 3,000W: an electric range element, a large well pump, a welder, or several heavy loads running at once. Below that line it is headroom you paid for and never touch.
AC300 stack inverter: 3,000W continuous, 6,000W surgeAC500 stack inverter: 5,000W continuous, 10,000W surgeevery modeled scenario peaks at 400W or less, and the AC300 starts and sustains all of them
Why it mattersName your single biggest load. Over 3,000W, buy the AC500 stack. Under it, the AC500's inverter edge is invisible and the AC300's battery edge is not.
The AC300's risk is not a higher failure rate — early dead-on-arrival units turned up on both platformsB7. It is that when the discontinued unit fails, there is nothing to repair it withA10, while the in-production AC500 can still be serviced.
AC300 stack: 3,500 cycles, 43,008 lifetime kWh, $0.13 per kWh — the cheapest energy herethe AC300 is discontinued and one owner's failed head unit had no repair parts leftA9A10a reviewer found both AC300 and AC500 test units arrived with a dead inverterB7
Why it mattersIf you will keep it under warranty and don't mind an end-of-life platform, the value is real. If a discontinued, unrepairable box on a $5,596 spend unsettles you, that is the one solid reason to take the AC500 stack.
For a unit that sits armed 24/7 and rarely discharges, the AC500 platform wastes less doing nothing. For cyclic off-grid use where you're draining it daily anyway, the difference disappears into the AC300's much larger reserve.
AC300 idles near 60W with the AC on and no load, about 8% of a single battery over four hoursA2A3an AC500 owner measured about 31W running as a UPSB5
Why it mattersGrid-tied UPS that is almost never called on: the AC500's lower standby is a quiet point in its favor. Daily-cycle off-grid: ignore it and buy on capacity.
The specific dimensions that decide these two units — everything else is a tie.
Lifetime Value
Selected because: The AC300 stack stores energy cheaper both ways — $0.46 vs $0.71 per Wh today, $0.13 vs $0.20 per lifetime kWh — so cost-to-own is the first thing separating two same-brand, same-cycle stacks.
cost / lifetime kWh
Two BLUETTI stacks, the same 3,500-cycle cells, and the bigger one is the cheaper energy. The AC300 stack works out to $0.13 per lifetime kilowatt-hour, the AC500 stack $0.20, because $5,596 spread over 43,008 lifetime kWh beats $3,948 over 19,355. So the big stack isn't the premium option; it's the value one.
The intuition that more battery costs more per unit is exactly backwards here. You pay 42% more up front ($5,596 vs $3,948) and get 122% more energy (12,288Wh vs 5,530Wh), which is why the per-kilowatt-hour line lands where it does.
Runtime: Will It Power Your Gear?
Selected because: Capacity is the axis: 12,288Wh vs 5,530Wh, or 10,445 vs 4,701 usable, which is how long each lasts once the load is measured in days rather than hours.
continuous output
Capacity is the whole gap: 12,288Wh in the AC300 stack, 5,530Wh in the AC500 stack. After the flat 15% usable-energy derate both get scored against, that's 10,445 usable watt-hours to 4,701 — more than two of the AC500 stack's tanks in one box.
For anything measured in days rather than hours — a multi-day outage, off-grid living, a worksite between grid tie-ins — that reserve is the product. Hours of runtime is a spec both clear easily; days of it is where only the bigger stack keeps going.
Your Life, Your Pick
Selected because: The capacity gap turns into outcomes here — the AC500 stack hits 100% of its battery on a van-life day while the AC300 stack sits at 45%.
Where the capacity gap stops being abstract is a full day of van life: the AC500 stack ends it having used 100% of its battery, 16 watt-hours from empty, while the AC300 stack sits at 45% with 5,760Wh untouched. Miss one solar day on the AC500 stack and you're dark. Miss one on the AC300 stack and you barely notice.
The blackout rhymes. After an eight-hour outage the AC300 stack has 8,800Wh left, 5.3 more nights like it, against the AC500 stack's 3,056Wh and 1.9. Both survive the night; only one survives the week.
PowerScore Breakdown
Selected because: The composite (8,760 vs 5,894) rewards the AC300 stack on capacity but under-weights the AC500's 5,000W inverter, so it is worth reading with that caveat.
overall power score
Our PowerScore lands the AC300 stack at 8,760 and the AC500 stack at 5,894, and that gap is almost entirely capacity — the score rewards the bigger battery, which is fair for how these actually get used. What it doesn't price in is the AC500's 5,000W inverter, the one spec where the smaller stack is the stronger machine. Read the score as which stores more, not which is better at everything, and it tells the truth.
What the Specs Don't Tell You
Selected because: Both are stationary, so the 171-pound weight gap (367 vs 196 lbs) decides install logistics, not portability — neither one travels.
Both of these are furniture. The AC500 stack is 196 pounds, the AC300 stack 367, a 171-pound spread that only bites once, on install day, and never again, because neither is moving after you set it down. Plan the spot before the truck arrives: a floor that won't flinch at 367 pounds, close to what it's backing up. You site this like a water heater, not stash it like a cooler.
Strengths & trade-offs
BLUETTI AC300 + 4×B300
Strengths
- +Larger battery capacity
Trade-offs
- –Substantially more expensive (+$1,648) than the AC500 + 2×B300K.
- –Significantly heavier (+171.1 lbs), making it harder to move.
- –Weaker inverter (-2,000W) limits appliance compatibility.
- –Very heavy unit that may be difficult for one person to lift.
BLUETTI AC500 + 2×B300K
Strengths
- +Costs $1,648 less
- +Lighter by 171.1 lb
- +Higher AC output
- +Faster solar charging
Trade-offs
- –Very heavy unit that may be difficult for one person to lift.
Will It Power Your Gear?
Scenario math and per-appliance runtimes, modeled from the spec record.
Scenario verdicts
We ran the math on six real-world scenarios. Here's which unit survives your actual life.
SCN-01 · 2 nights · needs 2,100Wh
Weekend Camping
Two nights off-grid with essential comfort
Neither unit
Scoring these two at a campsite is a category error: neither travels — the AC300 + 4×B300 is 367.2 lbs and the AC500 + 2×B300K 196.1 lbs, and at those weights they roll off a truck bed if they go anywhere at all. The 2,100Wh here is trivial for either — it's the going that doesn't happen. If you need power away from the building, you're shopping the wrong class.
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
AC300 + 4×B300
Both survive the night. The AC300 + 4×B300 finishes at 16% used with 8,800Wh left — 5.3 more nights like it. The AC500 + 2×B300K finishes at 35% with 3,056Wh, 1.9 more nights like it. If your outages tend to run past one evening, that difference is the whole argument between them.
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 sips about 40W, so over eight hours it needs roughly 320Wh — 3% of the AC300 stack's battery and 7% of the AC500 stack's. Capacity is irrelevant here; both could run your machine for a week of nights. Neither BLUETTI publishes a fan-noise figure, so the spec that actually matters two feet from your pillow is the one you can't read off the box. Decide on price and on whether you've heard the fan you're about to sleep beside.
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
AC300 + 4×B300
The AC300 + 4×B300 clears the workday at 9% used, banking 9,535Wh — late work, extra calls, or a second laptop charge without arithmetic. The AC500 + 2×B300K at 19% also finishes, with 3,791Wh of slack for the unplanned.
Battery budget usedlower = more headroom
LOAD Laptop 60W×8h · External Monitor 30W×8h · Router + Modem 20W×8h · Phone Charger 15W×2h
SCN-05 · 4 hours · needs 670Wh
Tailgate Party
Game day power for the crew
Neither unit
Scoring these two at a tailgate is a category error: neither travels — the AC300 + 4×B300 is 367.2 lbs and the AC500 + 2×B300K 196.1 lbs, and at those weights they roll off a truck bed if they go anywhere at all. The 670Wh here is trivial for either — it's the going that doesn't happen. If you need power away from the building, you're shopping the wrong class.
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
AC300 + 4×B300
The AC500 + 2×B300K uses 100% of its battery on a full day, leaving 16Wh — miss a solar day and that is the entire cushion. The AC300 + 4×B300 at 45% keeps 5,760Wh in hand, a far more forgiving rhythm for full-time living.
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: AC300 + 4×B300 runs 51h vs 22.9h.
$5,596 list · direct from BLUETTI
Planning for more than this? Describe your whole setup and get it sized →
Modeled from the spec record — same math as the tables below. Methodology
Runtime by appliance
Real-world runtime estimates for common appliances, modeled at 85% inverter efficiency.¹
Essentials
The basics you need runningscale 0–696.3hComfort & Convenience
Makes off-grid life actually enjoyablescale 0–139.3hHigh-Draw Appliances
These reveal the real limitsscale 0–10.4h¹ 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 30, 2026
Verdict: the BLUETTI AC300 + 4×B300
Buy the AC300 + 4×B300 for the job most people buy this class to do: store energy. It holds 12,288Wh to the AC500 stack's 5,530, costs $0.13 per lifetime kilowatt-hour against $0.20, and takes all three scenarios that resolve to a single winner — blackout, remote workday, van life — with room to spare where the AC500 stack runs its battery flat. You pay $1,648 more for 6,758Wh more battery, so per watt-hour the bigger stack is the cheaper one. Two real caveats hold this to moderate confidence. The AC300 is discontinued, and one owner whose head unit failed was told no repair parts remainA9A10, so the cost-to-own math assumes it lives. And its 3,000W inverter, plenty for every load we model, can't start something the AC500's 5,000W can. If your heaviest load stays under 3,000W and you want the most stored energy per dollar, take the AC300 stack. If you need the bigger inverter or the current, still-serviced platform, the AC500 stack is the right — and cheaper — call.
Today the AC500 + 2×B300K is $3,299, $649 under its typical $3,948. The verdict weighs typical prices, not today's. Prices checked 16 days ago.
Editor-assigned confidence, based on cited owner research and spec analysis.
List prices as of August 30, 2026. The links below open BLUETTI's current price.
$5,596.00 · direct from BLUETTI
Last checked 16 days ago. Prices move — check before you buy.
or check the AC500 + 2×B300K price$3,299.00 list
Written by Gunner Gustafson, Whole-Home Backup Tester · Station Arena Test Desk · Updated August 30, 2026
Black Friday · 38 days out
Prices to beat:AC300 + 4×B300 $5,596AC500 + 2×B300K $3,299
The lowest we have recorded for each. We have never seen the AC300 + 4×B300 discounted, so any real cut on it would be a first.
Measured Data
Benchmark scores and the full spec record, side by side.
Benchmark scores
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, AC300 + 4×B300 rates 3.3/5 (1st percentile of 29 Whole-Home / Off-Grid-class units), and AC500 + 2×B300K rates 4.1/5 (47th percentile of 20 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.
Neither one moves twice
196 pounds is a two-person lift you do once and resent. 367 pounds isn't a lift at all — it's four batteries you site individually and a head unit you set down where it lives for good. The 171-pound gap between them only matters on delivery day; after that, both are furniture. Pick the location before the truck arrives, not after.
AC500 + 2×B300K: Power Lifting to 6,000W
The AC500 + 2×B300K has BLUETTI's Power Lifting mode, which runs a resistive appliance rated up to 6,000W from its 5,000W 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; for motor loads the figure to read is the AC500 + 2×B300K's separate 10,000W surge peak, not this one. And it is not a reason to size down, because running a load that big from 5,530Wh is a short session either way. Genuinely useful if a heater or a kettle is why you're buying; beside the point otherwise. Our record for the AC300 + 4×B300 carries no Power Lifting figure, only a 6,000W surge peak, which is a different rating, so check BLUETTI's own spec sheet before reading this as something the AC300 + 4×B300 lacks.
Warranty: No Difference
Both units carry the same 4-year warranty, so coverage isn't a tiebreaker here. Worth saying because the per-dollar framing can suggest otherwise: the AC500 + 2×B300K works out at 1 years of cover per $1,000 spent against the AC300 + 4×B300's 0.7, but that spread is the price gap, not the terms.
Full record above — the Test Desk pick is the AC300 + 4×B300.
Check AC300 + 4×B300 price →or check the AC500 + 2×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
The AC500 + 2×B300K is cheaper to buy, but the AC300 + 4×B300 is cheaper to own. At $0.13/kWh over its lifetime vs $0.20/kWh, the AC300 + 4×B300'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 3,500-cycle rating, so the lifetime rows are sticker price and capacity in disguise — the wear horizon is identical and decides nothing here.
Growth path
AC300 + 4×B300
EXPANDABLESupports BLUETTI expansion batteries, so you can add capacity later without replacing the base unit — useful if your needs may climb past 12,288Wh.
Accepts up to 2,400W of solar. Enough for a serious multi-panel array.
Adequate ports for most setups, but heavy users may want a power strip.
Expansion batteries are BLUETTI-specific. You're investing in the BLUETTI ecosystem.
AC500 + 2×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 3,000W of solar. Enough for a serious multi-panel array.
Adequate ports for most setups, but heavy users may want a power strip.
Expansion batteries are BLUETTI-specific. You're investing in the BLUETTI ecosystem.
Realistic full solar rechargeat 70% of rated panel output — see methodology
Analyst note
Both expand, so neither locks you out of growth — decide on capacity, price, and the rest, not the expansion checkbox.
What Owners Report
Patterns from published owner reports and long-term reviews — every claim cited to its source below.
BLUETTI AC300 + 4×B300
The AC300 + B300 is a mature, heavily reviewed 2021 platformA0, and owners tend to like it in the hand: one reviewer was "immediately impressed with the unit's quality, finish, and clever design"A1, another clocked it recharging from near-empty to full in just over an hourA4 and holding a fridge for about 31 hours on a chargeA11. Two gripes recur. Idle draw is high, near 60W with the AC on and nothing plugged in, enough to eat roughly 8% of a single battery over four hoursA2A3. And the app is basic, with some owners fighting a pairing that loads forever even while the unit reports itself connectedA7A8. Fan noise splits the room: audible but easy to forget for its size to one reviewerA5, "extremely quiet" to anotherA6.
The finding that should shape the decision sits at the end of the unit's life, not the start. After several years some head units fail outright, and because the AC300 is discontinued BLUETTI has told owners it no longer stocks the parts to repair themA9A10. That doesn't make failure likely, but it changes what failure costs.
“I was immediately impressed with the unit's quality, finish, and clever design.”
Sources
reviewed.com
BLUETTI AC500 + 2×B300K
Field data on the AC500 is thinner, and none of it is on this exact two-battery stack. Every report is the AC500 with a single B300K, the same inverter and the same battery model wired one-to-one instead of one-to-two, so double the runtime figures but carry the fan, app, and support findings straight overB0. In use, owners are happy: one found it "much quieter than" his previous power stationB1 and drawing about 31W as a UPSB5, another said it "performed near flawlessly from day one"B12.
The knocks are early-life and interface. A reviewer found both AC300 and AC500 samples arrived with a dead inverterB7, one owner's kit shipped missing the cable that links battery to inverterB6, the display shows only battery percentage with no time-remaining and no voltageB2, and there's no hard-reset button when it glitchesB8. One more worth knowing for a bedroom: a reviewer warns the indicator lights stay bright all night, so it's "best not to keep the AC500 in a room where you'll be sleeping"B11.
“So far pretty darn happy, and it's much quieter than the small Pecron E1500LFP I have.”
Sources
firewoodhoardersclub.com · thesolarlab.com · freshlycharged.com · diysolarforum.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
- Idle power draw is noticeably higher than expected and drains meaningful battery even with no connected load. [AC300 + 4×B300 · 2 entries]
- Reviewers and owners consistently describe the AC300's fan as audible under load but notably quiet for its size and class. [AC300 + 4×B300 · 2 entries]
- The companion app is described as basic/limited, and some owners report Bluetooth or app-pairing problems connecting to the AC300+B300. [AC300 + 4×B300 · 2 entries]
- After several years of service, some head units fail outright, and once discontinued Bluetti has no repair parts and does not recommend repairing out-of-warranty units. [AC300 + 4×B300 · 2 entries]
- Multiple sources report AC500 units arriving with hardware faults — a dead inverter or a missing battery-link cable — that required contacting Bluetti support. [AC500 + 2×B300K · 2 entries]
- Fan noise is intermittent but noticeable during charging/heavy load across sources, though one owner found it quieter than a competing unit. [AC500 + 2×B300K · 2 entries]
- The app covers the basics but owners want more detail (time-remaining, battery voltage), and the unit lacks a hard-reset option to recover from glitches. [AC500 + 2×B300K · 2 entries]
- A1
“I was immediately impressed with the unit's quality, finish, and clever design.”
Clean Energy Reviews Forum — "Bluetti Power Station Review (AC300) Off-grid Backup" (user Svarky) · 2023-07 · [positive]
- A2
“When the AC output is switched on, the idle power draw (with no load) appears to be close to 60W, which is high.”
Clean Energy Reviews Forum — "Bluetti Power Station Review (AC300) Off-grid Backup" (user Svarky) · 2023-10 · [negative]
- A3
“When left on for 4 hours with no load, it consumed around 8% of the battery, which was rather surprising.”
Clean Energy Reviews Forum — "Bluetti Power Station Review (AC300) Off-grid Backup" (user Svarky) · 2023-10 · [negative]
- A4
“It still charges the battery from near empty to 100% in just over one hour, which is very good.”
Clean Energy Reviews Forum — "Bluetti Power Station Review (AC300) Off-grid Backup" (user Svarky) · 2023-10 · [positive]
- A5
“The AC300 + B300 has a little bit of noise coming from the fan. It's NOT silent. But considering the size and use case... you'll forget it's there.”
GreenCitizen — "Bluetti AC300 + B300 Power Station Review: Real-Life Lab Test Results" · 2025-01 · [positive]
- A6
“The powered fans within my AC300 units are extremely quiet when running – no detectible motor or bearing noise; only air movement is slightly heard.”
DIY Solar Power Forum — "Fan noise level of Bluetti AC200MAX?" thread (AC300 owner's comparison reply) · unknown · [positive]
- A7
“The companion app brings basic functionality to your fingertips but leaves you longing for more.”
GreenCitizen — "Bluetti AC300 + B300 Power Station Review: Real-Life Lab Test Results" · 2025-01 · [negative]
- A8
“App (v3.0.1) keeps loading indefinitely even when the AC300 itself shows it is "Connected."”
BLUETTI Community forum — "AC300+B300 doesn't connect to Bluetti App" thread · unknown · [negative]
- A9
“I just had my AC300 head unit fail with a007 App error, and 00 006 and 01 006 errors on the console screen and 2 days later.... click click click.. DEAD.”
DIY Solar Power Forum — "Bluetti - Screw you - AC300 dead and no parts to fix it anymore 5 years after launch" · 2026-03 · [negative]
- A10
“Due to the AC300 being discontinued, they don't have the necessary parts for repairs. Considering the repair costs and round-trip shipping fees, we don't recommend repairing it.”
DIY Solar Power Forum — "Bluetti - Screw you - AC300 dead and no parts to fix it anymore 5 years after launch" (Bluetti support reply relayed by OP) · 2026-03 · [negative]
- A11
“The Bluetti AC300 + B300 combo kept the fridge running for an average of 31 hours on a charge.”
Forbes — Brad Moon, "Review: Bluetti AC300 + B300 Home Battery Backup System" · 2023-10 · [positive]
- B1
“So far pretty darn happy, and it's much quieter than the small Pecron E1500LFP I have.”
firewoodhoardersclub.com — jtakeman, "Bluetti AC500 w/B300K battery for our home backup/supplement system install and review" · 2025-02 · [positive]
- B2
“One other odd thing — it doesn't have a time-of-charge-remaining readout like my EF or Pecron units, just battery percentage. They don't even display battery voltage.”
firewoodhoardersclub.com — jtakeman, AC500 w/B300K install and review thread · 2025-02 · [negative]
- B5
“Using about 31 watts an hour as a UPS — at 85% that should last about 8+ hours. Priceless!!”
firewoodhoardersclub.com — jtakeman, AC500 w/B300K install and review thread · 2025-03 · [positive]
- B6
“Got a hold of Bluetti support — seems they forgot to ship the cable connecting the main unit to the battery.”
firewoodhoardersclub.com — jtakeman, AC500 w/B300K install and review thread · 2025-02 · [negative]
- B7
“Both the AC300 and AC500 we tested had issues where the battery would turn on but not the inverter itself — dead on arrival, essentially.”
thesolarlab.com — Bluetti AC500 Review: Pros, Cons & the Ugly Truth · unknown · [negative]
- B8
“The lack of a hard reset button on these units is also really frustrating.”
thesolarlab.com — Bluetti AC500 Review: Pros, Cons & the Ugly Truth · unknown · [negative]
- B11
“The indicator lights are quite bright and remain on all the time, so it's best not to keep the AC500 in a room where you'll be sleeping.”
freshlycharged.com — Powering A Room with Solar: Bluetti AC500 & B300K Review · unknown · [negative]
- B12
“Performed near flawlessly from day one, with easy-to-understand setup and a nice app for monitoring.”
diysolarforum.com — "Bluetti ac 500" owner thread · unknown · [positive]
Research compiled August 30, 2026.
Who Should Buy Which
Buy the AC300 + 4×B300 if you…
- →The long-outage, off-grid, or van-life buyer who wants the most stored energy per dollar: 12,288Wh at $0.13 a lifetime kilowatt-hour, more than double the AC500 stack's reserve for 42% more money.
- →The homeowner arming a multi-day backup who would rather wake to 8,800Wh still in the tank after an eight-hour outage than to a stronger inverter they never load past 3,000W.
- →Anyone whose heaviest single load stays under 3,000W and who is comfortable buying the current-warranty life of a platform that is now end-of-lifeA10.
Buy the AC500 + 2×B300K if you…
- →Anyone with a single load over 3,000W: an electric range element, a large well pump, a welder, or several heavy 120V loads at once. The 5,000W inverter with 10,000W of surge is the only thing here that starts them.
- →The buyer whose needs fit inside 5,530Wh and who wants BLUETTI's current, still-serviceable platform and the lower $3,948 sticker over the discontinued AC300A10.
- →Whoever will actually reposition it or lean on solar daily: at 196 lbs it's 171 lighter than the AC300 stack and takes 3,000W of panels to the AC300 stack's 2,400W.
If neither fits
If you're shopping for camping, a tailgate, or a bedside CPAP backup, both are the wrong class. These are 196-to-367-pound house batteries: the scenarios that involve going somewhere they can't do, and the 40W CPAP they cover while using 3 to 7% of the battery. For power you carry, buy a much smaller portable a fraction of the size and price; you'll spend less, and it will actually leave the driveway.
The Bottom Line
The AC300 + 4×B300 is the one to buy for the reason you buy a battery this size: it stores the most energy for the money. Twice the reserve of the AC500 stack, cheaper per kilowatt-hour over an identical 3,500-cycle life, and enough headroom that it ends a full van-life day at 45% while the AC500 stack ends it on 16 watt-hours. Its 3,000W inverter covers every load a house actually hands it.
Two things send a buyer the other way, and only two. If a single load tops 3,000W, the AC500's bigger inverter is the only one that starts it. And if buying a discontinued unit with no repair partsA9A10 keeps you up at night, the AC500 is the current platform, for $1,648 less if half the battery. Everyone else: get the big stack, and put it somewhere you won't need to move it.
Frequently Asked Questions
Answers drawn from the spec record and cited owner research.
Is the Bluetti AC300 discontinued?
Yes. It launched in 2021 and BLUETTI has since discontinued it, with the AC500 the current stack. It still performs well, its cells are rated for 3,500 cycles, and this build carries a 4-year warranty, but one owner whose head unit failed was told no repair parts remain — so weigh out-of-warranty repairability before you buy.
Bluetti AC300 vs AC500: what's the real difference?
They optimize for opposite things. The AC300 in this build is a 3,000W inverter on a big 12,288Wh battery; the AC500 is a stronger 5,000W inverter on a smaller 5,530Wh battery. Buy the AC300 stack for runtime and cost per kilowatt-hour, the AC500 stack for the ability to start loads above 3,000W.
Can the Bluetti AC300 run a whole house?
It runs circuits and essentials, not the whole panel. 3,000W comfortably covers a fridge, lights, electronics, and a microwave one at a time, but not a big electric range element or a well pump. For heavier simultaneous loads the AC500's 5,000W is the better single-inverter answer; for whole-home backup, neither single unit here is built to be that.
Which Bluetti stack is cheaper to run over time?
The AC300 + 4×B300, and not by a little: $0.13 per lifetime kilowatt-hour versus $0.20 for the AC500 stack. Both use the same 3,500-cycle cells, so spreading a similar lifespan over 12,288Wh instead of 5,530Wh is what drops the per-kWh cost. You pay 42% more up front ($5,596 vs $3,948) and get 122% more capacity.
Are the AC300 and AC500 portable?
Not in any real sense. The AC500 stack is 196 pounds and the AC300 stack 367, both two-person, set-it-and-leave-it installs. Treat them as appliances you place near what they back up, not gear you carry to a campsite. If you need to move it, you're looking at the wrong class of product.
Where to buy
BLUETTI AC300 + 4×B300Pick
$5,596.00
$5,596.00 · direct from BLUETTI
Last checked 16 days ago. Prices move — check before you buy.
BLUETTI AC500 + 2×B300K
$3,299.00
$3,299.00 · direct from BLUETTI
down from $3,948 · 16% below usual
Last checked 16 days ago. Prices move — check before you buy.
Prices may vary by retailer and are subject to change.