Head-to-head test
BLUETTI AC300 + 4×B300 vs BLUETTI EP500
Real-world runtimes, scenario verdicts, and ownership costs compared — which wins for your use case.
Full profiles: BLUETTI AC300 + 4×B300 → · BLUETTI EP500 →
Written by Gunner GustafsonUpdated
Whole-Home Backup Tester, Station Arena Test Desk
Spec deltas
Both carry the BLUETTI name, but they're built for different buyers. The AC300 + 4×B300 (12,288Wh, 3,000W) and the EP500 (5,120Wh, 2,000W) come from different product lines with different engineering priorities and a $2,597 price gap. The AC300 + 4×B300 has a slight edge, but the margin is close enough that your use case should break the tie.
What the spec gap means in practice: the AC300 + 4×B300's 3,000W inverter has the headroom for a window AC, a full-size fridge, and power tools. The EP500's 2,000W inverter still runs most single appliances; the AC300 + 4×B300's real edge is surge headroom for the biggest motor starts and stacking several heavy loads at once. On stamina, the AC300 + 4×B300 keeps a fridge alive for roughly 70 hours vs the EP500's 29 hours. The cost? Portability. At 367.2 lbs, the AC300 + 4×B300 is spread across boxes you site once and leave. The EP500 at 167 lbs is more manageable, though still not light.
Pick the AC300 + 4×B300 if your primary use is 8-hour blackout or remote workday. Go with the EP500 if its specific strengths below line up better with your use. Keep scrolling for the full breakdown. The scenario verdicts below hold a few surprises.
Bench Notes
What each unit does well, where it falls short, and the trade-offs that matter.
BLUETTI AC300 + 4×B300
With a massive 3,000W output (and 6,000W surge), the AC300 + 4×B300 can run high-wattage appliances like space heaters, hair dryers, and electric grills without tripping. Weighing in at 367.2 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
- +Higher AC output
- +Faster solar charging
Trade-offs
- –Significantly heavier (+200.2 lbs), making it harder to move.
- –Very heavy unit that may be difficult for one person to lift.
BLUETTI EP500
The 2,000W inverter handles most daily devices like laptops, blenders, and TVs, but will struggle with heating elements that require over 1500W. Weighing in at 167 lbs, this is not a unit you want to carry far. It's best suited as a stationary backup or RV companion.
Strengths
- +Lighter by 200.2 lb
- +Longer warranty
Trade-offs
- –Weaker inverter (-1,000W) limits appliance compatibility.
- –Very heavy unit that may be difficult for one person to lift.
- –Sealed capacity — the AC300 + 4×B300 can add batteries to grow past 5,120Wh; this one can't.
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 EP500 167 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 EP500 finishes at 38% with 2,707Wh, 1.6 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 is about 40W for eight hours, so both of these cover the night several times over — capacity isn't the question here. What would separate them is fan noise, but neither maker publishes a fan-noise figure, so there's nothing to hold either of them to. Neither is sold new any more, so weight and fan noise is what's left to weigh, alongside whatever you can find used.
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 EP500 at 21% also finishes, with 3,442Wh 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 EP500 167 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 EP500 doesn't finish — 4,352Wh usable against the 4,685Wh this needs leaves it 333Wh short, about 93% of the scenario covered (its nameplate 5,120Wh actually clears this — the flat 15% conversion allowance is what tips it under). The AC300 + 4×B300 covers it with 5,760Wh to spare.
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 21.2h.
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
July 10, 2026
Verdict withdrawn: the AC300 + 4×B300 is no longer sold
We picked the AC300 + 4×B300, but neither unit is sold new any more. The comparison below still helps if you own one.
Overall score margin: 8,742 vs 4,720 (+85.2%)
Written by Gunner Gustafson, Whole-Home Backup Tester · Station Arena Test Desk · Updated July 10, 2026
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.
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 (3rd percentile of 37 Whole-Home / Off-Grid-class units), and EP500 rates 3.4/5 (5th 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.
Weight Reality Check
Neither unit is grab-and-go. The EP500 (167 lbs) is a two-person lift. The AC300 + 4×B300 (367.2 lbs) is spread across its boxes — no single lift, but nothing you reposition on a whim. That's a 200 lb difference, and it is paid once — getting the heavier one into position, not every time you move it.
EP500: Fixed Capacity
The EP500 is sealed at 5,120Wh, and that is the ceiling. Normally the counterpoint would be that the AC300 + 4×B300 can add expansion batteries, but that isn't a live option here: the AC300 + 4×B300 is no longer sold, and BLUETTI points owners to the Apex 300 + 2*B500K. For a new purchase the expansion question doesn't arise between these two, so the EP500's fixed 5,120Wh is simply what you get.
Surge Power: Ratio and Ceiling Disagree
The EP500 holds the higher surge-to-continuous ratio (2.4× vs 2×), but the AC300 + 4×B300 holds the higher absolute surge ceiling — 6,000W against 4,800W. These measure different things. The ratio says how much headroom an inverter keeps above its own rating; the ceiling says how big a startup spike it can actually swallow. A motor draws a number of watts at switch-on, not a multiple of someone else's rating, so on raw starting ability the AC300 + 4×B300 is the stronger unit here — while the EP500 is the one running further below its own limit at steady state.
Warranty: 5 Years vs 4
The EP500 is covered for 5 years against the AC300 + 4×B300's 4 years. The EP500's figure is a maximum rather than a guarantee — it depends on buying direct from BLUETTI or registering the unit, since reseller purchases carry a shorter term. An underrated factor if you're keeping this unit for years.
Ownership 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
│ warranty ends · Reaching the cycle rating means ~80% capacity remains — degraded, not dead.
Analyst note
Neither is sold new any more, so there is no price left to work a cost per kWh from, and what either costs you now depends on the used market. The hardware comparison still holds: over its rated life the AC300 + 4×B300 delivers about 43,008 kWh and the EP500 about 17,920 kWh. 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.
EP500
FIXED CAPACITYFixed at 5,120Wh — 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 1,200W of solar. Enough for a serious multi-panel array.
Adequate ports for most setups, but heavy users may want a power strip.
Realistic full solar rechargeat 70% of rated panel output — see methodology
Analyst note
Neither of these is sold new any more, so there is no growth path to buy into on either side. If you already own one: the AC300 + 4×B300 takes expansion batteries and the EP500 is fixed at 5,120Wh. As a purchase decision, expandability isn't the question here.
The Bottom Line
The full picture comes down to this. The AC300 + 4×B300 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 EP500 wins in the scenarios that match your life, it's the right choice regardless of aggregate scores.
If neither the AC300 + 4×B300 nor the EP500 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 BLUETTI discount regularly, so check the current price before committing. Prime Day and Black Friday pricing typically drops 20-30%.
Frequently Asked Questions
Answers drawn from the spec record and cited owner research.
How does the 7,168Wh capacity difference actually affect daily use?
The AC300 + 4×B300's 12,288Wh battery keeps a mini-fridge running for roughly 70 hours vs the EP500's 29 hours. Both can handle a full 8-hour blackout setup (fridge + router + lights + phone charging ≈ 1,645Wh), but the AC300 + 4×B300 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 AC300 + 4×B300'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 AC300 + 4×B300, or is the EP500 the only portable option?
Neither is "portable" in any hiking sense. The EP500 (167 lbs) and the AC300 + 4×B300 (367.2 lbs) are both appliances you place and leave. The 200.2-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 AC300 + 4×B300 accepts 2,400W vs the EP500's 1,200W of solar input. What the spec sheet won't tell you: solar panels typically deliver only 60-80% of their rated output due to panel angle, cloud cover, and temperature. In realistic conditions, expect full recharge in about 7.3 hours for the AC300 + 4×B300 and 6.1 hours for the EP500. That gap widens on cloudy days, when the AC300 + 4×B300'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 AC300 + 4×B300's advantage is substantial.
What if I need more capacity than the EP500's 5,120Wh later?
The EP500 is sealed at 5,120Wh, so if you expect your needs to climb, the AC300 + 4×B300 is the more future-proof pick: it starts at 12,288Wh and adds BLUETTI-compatible batteries without replacing the base unit. That said, "not expandable" isn't a flaw on its own — if 5,120Wh comfortably covers your loads, the EP500 is a complete unit, not a downgrade.
Bottom line: should I buy the AC300 + 4×B300 or the EP500?
Neither, if you're buying new: both are no longer sold. The comparison on this page still helps if you own one.
Where to buy
BLUETTI AC300 + 4×B300
Sold out at BLUETTI
BLUETTI EP500
Sold out at BLUETTI
Prices may vary by retailer and are subject to change.