Head-to-head test
BLUETTI Apex 300 + B300K vs BLUETTI EP900 + 3×B500
One of these you buy and the other you install, and the $11,199 between them only starts paying for itself after an electrician has been to your house.
Full profiles: BLUETTI Apex 300 + B300K → · BLUETTI EP900 + 3×B500 →
Written by Gunner GustafsonUpdated
Whole-Home Backup Tester, Station Arena Test Desk
$2,599.00 · direct from BLUETTI
Last checked 1 day ago. Prices move — check before you buy.
$13,798.00 · direct from BLUETTI
Last checked 1 day ago. Prices move — check before you buy.
Spec deltas
The EP900 costs $13,798 and it is not overpriced. That's the uncomfortable part. Per watt-hour of storage it runs about 93 cents against the Apex stack's 47 (each price divided by its rated capacity), and across the cycles each is rated for, the two finish two cents apart: 15 cents per lifetime kilowatt-hour against 13. The expensive system is priced fairly for what it is. It just isn't what most people opening this page are shopping for.
The Apex 300 + B300K is two boxes stacked to 148.8 lbs that run off a wall outlet. The EP900 + 3×B500 is a 9,000W inverter and three battery modules, 466 lbs all in, wired to your panel and then left alone for a decade. Everything below follows from that, including the rows the EP900 wins.
Take the Apex unless a whole-home install is genuinely the plan. 4,700Wh of usable energy covers every load modelled here, including an eight-hour blackout that leaves 3,055Wh untouched. The EP900's case begins exactly where the Apex's ceiling is: more than 2,400W of panels, more than 3,840W of load, or a daily draw that empties the pack every single day.
What the Numbers Reveal
Each conclusion stated first — the numbers behind it on one line, the full analysis below.
Capacity
The reason is throughput. The Apex is rated to move 19,354 kWh before it fades; the EP900, 89,280. The premium isn't margin, it's more battery running longer, and the only way to collect it is to consume it. At weekend use the EP900's rated life comes out at 57.7 years, which isn't a payback period so much as a geological one.
Apex 300 + B300K: $2,599 for 5,529.6Wh ratedEP900 + 3×B500: $13,798 for 14,880Wh ratedCycle ratings: 3,500 for the Apex stack, 6,000 for the EP900
Why it mattersDon't buy the EP900 on cents per kilowatt-hour. If it's right for you, it's right because you need 9,000W and 12,648Wh this year.
Refilling 4,685Wh through a 2,400W ceiling takes about two hours at the full rated input, and no array holds its nameplate figure for two straight hours. So the Apex doesn't fail a 4,685Wh day on capacity, it fails on repetition: you have to win the recharge every single day, and the first overcast one puts you short before breakfast. The EP900 takes 9,000W in and holds 12,648Wh usable, which is why it takes the row, and it is also bolted to a building.
Van Life Daily models a 4,685Wh dayThe Apex stack's usable energy is 4,700Wh (5,529.6Wh × 0.85 for inverter losses)The Apex accepts a maximum of 2,400W of solar
Why it mattersIf you genuinely draw 4,685Wh a day off-grid, neither of these is the answer as configured. A second B300K adds about 2.7kWhA13, and that's the upgrade to price out first.
continuous output
What those two ratings mean physically matters more than the missing one. 3,840W is what an outlet delivers; 9,000W is what a panel delivers, and you get there by paying someone to tie three battery modules and an inverter into your service. The 466 lbs isn't a portability penalty you're absorbing. It's the receipt for having bought a fixture.
Apex stack: 3,840W continuous, 7,680W surgeEP900: 9,000W continuous, with no surge figure carried in our spec tableWeights are sums across chassis: 148.8 lbs over two boxes, 466 lbs over four
Why it mattersIf your plan doesn't include an electrician, the EP900's advantages are unreachable and this comparison is already over.
The specific dimensions that decide these two units — everything else is a tie.
Lifetime Value
Selected because: Two prices five times apart land two cents apart per lifetime kilowatt-hour, 13 against 15, and that deserves an explanation.
cost / lifetime kWh
Two cents per kilowatt-hour is the entire lifetime penalty for buying the bigger system, and it's the best argument the EP900 has. It's also the least useful one. Collecting 89,280 kWh means running the thing hard for a decade and a half, and the 16.4-year figure assumes you cycle it fully, daily, for all of them.
The number that will actually decide this is $11,199, sitting in your account or not. Per warranty year the Apex runs $520 against $1,380, and at weekend use it works out to 21 cents a day against 66. Both are cheap enough to ignore. Only one of them asks you to have $13,798 first.
Your Life, Your Pick
Selected because: The Apex covers five of the six loads modelled here with room to spare, and clears the sixth by 15Wh.
Only one row here is close, and it's the last one. A weekend camp draws 2,100Wh and leaves the Apex 2,600Wh in hand; an eight-hour blackout takes 1,645Wh and leaves 3,055Wh. Those aren't squeakers, whatever the percentages look like next to a 14,880Wh bank.
Van Life Daily is the exception. 4,685Wh against 4,700Wh usable is a 15Wh margin, a rounding error wearing a pass. The EP900 covers the same day at 37% and takes the row on merit. It also weighs 466 lbs across four chassis and gets wired into a building, so a van dweller reading that row should take it as proof the Apex is undersized for that draw, not as a shopping list.
Growth Path
Selected because: Both take expansion batteries, so the real growth question is solar input: 2,400W against 9,000W.
solar input
Both take expansion batteries, so "expandable" settles nothing between them. What separates the two is what can refill a bigger bank: 2,400W of solar into the Apex, 9,000W into the EP900. Filling 5,529.6Wh through a 2,400W ceiling is about 2.3 hours at rated input, which is one good morning. Feeding something three times that size through the same ceiling would be a full day of chasing the sun.
For an Apex owner the cheap move is a second B300K, roughly 2.7kWh moreA13, the same module that makes up half of what you already own. For an EP900 owner the growth path is more panels, which is the reason to have bought it.
What the Specs Don't Tell You
Selected because: The weight card below subtracts 148.8 lbs from 466 lbs as though you would be lifting either number.
The weight card is doing arithmetic on two numbers that describe different kinds of object. 148.8 lbs is an Apex 300 with a B300K stacked on it, two boxes that come apart. 466 lbs is an inverter plus three battery modules, weighed where they'll sit for the next decade. Subtracting one from the other produces 317 lbs of nothing.
The warranty card is the one worth reading twice, and followed honestly it argues against the cheaper unit. BLUETTI covers the Apex stack for 5 of its 9.6 rated daily-use years and the EP900 for 10 of its 16.4, so both terms track the hardware rather than flattering it. The per-dollar ratio flatters the Apex because the Apex is cheap. The absolute term is what counts when the thing needing service is wired into a wall.
Strengths & trade-offs
BLUETTI Apex 300 + B300K
Strengths
- +Costs $11,199 less
- +Lighter by 317.2 lb
Trade-offs
- –Weaker inverter (-5,160W) limits appliance compatibility.
- –Very heavy unit that may be difficult for one person to lift.
BLUETTI EP900 + 3×B500
Strengths
- +Larger battery capacity
- +Higher AC output
- +Longer warranty
- +Faster solar charging
Trade-offs
- –Substantially more expensive (+$11,199) than the Apex 300 + B300K.
- –Significantly heavier (+317.2 lbs), making it harder to move.
- –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
Two nights at 2,100Wh leave the Apex 2,600Wh of its 4,700 usable still in the pack, so 45% here is comfort, not caution. The EP900 takes the row on raw headroom, 12,648Wh usable against 4,700, and finishes at 17%. Both are overqualified for a weekend; only one of them can attend.
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
EP900 + 3×B500
Both finish the night, and the Apex finishes it with 3,055Wh unused, which is most of another one. The EP900 takes the row because 12,648Wh usable makes an eight-hour outage a 13% event with a second night already covered. Both hand over in 10ms, so the transition itself is a non-issue either way. If your outages run to days rather than hours, this is the row to weight.
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
Apex 300 + B300K
320Wh out of 4,700Wh usable is 7%, so capacity settled nothing here and the percentages are decoration. What settles it is which of these can be in the bedroom at all. The Apex is two boxes you set down where you need them; the EP900 lives wherever it was wired in, and that isn't beside your pillow.
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
EP900 + 3×B500
The EP900 + 3×B500 clears the workday at 7% used, banking 11,738Wh — late work, extra calls, or a second laptop charge without arithmetic. The Apex 300 + B300K at 19% also finishes, with 3,790Wh 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
670Wh for the whole afternoon: 14% of the Apex, 5% of the EP900. Call it a tie on capacity, because it is one. The tiebreak is attendance. 148.8 lbs across two boxes goes in a truck bed; 466 lbs across four chassis wired into a house does not.
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
Apex 300 + B300K
4,685Wh against the Apex's 4,700Wh usable is a 15Wh margin, three tenths of one percent, which is a pass in the sense that a photo finish is a win. The EP900 covers the same day at 37% and takes the row outright. Just note what it is while you read that: 466 lbs of inverter and battery modules wired into a building. At this draw the honest upgrade is more battery on the Apex.
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: EP900 + 3×B500 runs 61.7h vs 22.9h.
$13,798 list · direct from BLUETTI
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 0–843.2hComfort & Convenience
Makes off-grid life actually enjoyablescale 0–168.6hHigh-Draw Appliances
These reveal the real limitsscale 0–12.6h¹ 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 9, 2026
Verdict: the BLUETTI Apex 300 + B300K
Take the Apex 300 + B300K at $2,599 unless you are wiring a battery into your service panel. Its 4,700Wh of usable energy (5,529.6Wh rated, less the 15% the inverter takes) covers every scenario on this page, it costs 13 cents per lifetime kilowatt-hour against the EP900's 15, and it runs off a wall outlet. None of that makes the EP900 + 3×B500 a bad buy. At $13,798 it gives you 12,648Wh usable, 9,000W of output and a 9,000W solar ceiling, and it earns that premium back over 6,000 cycles. But those numbers only exist once three battery modules and an inverter have been connected to your house, and if that install isn't the project you're actually doing, you'd be paying five times as much for capability you can't reach.
Editor-assigned confidence, based on cited owner research and spec analysis.
List prices as of August 9, 2026. The links below open BLUETTI's current price.
$2,599.00 · direct from BLUETTI
Last checked 1 day ago. Prices move — check before you buy.
or check the EP900 + 3×B500 price$13,798.00 list
Written by Gunner Gustafson, Whole-Home Backup Tester · Station Arena Test Desk · Updated August 9, 2026
Measured Data
Benchmark scores and the full spec record, side by side.
Benchmark scores
Not rated for both units (minimum threshold unmet): Solar Generator.
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, Apex 300 + B300K rates 4.4/5 (67th percentile of 16 Home Backup-class units), and EP900 + 3×B500 rates 4.2/5 (54th percentile of 29 Whole-Home / Off-Grid-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.
What These Two Weights Describe
148.8 lbs is an Apex 300 with a B300K stacked on top, two boxes that separate. 466 lbs is a 9,000W inverter plus three B500 modules, weighed where they will sit for the next decade and a half. Subtract one from the other and you get 317 lbs of nothing, because nobody carries the second number. Read these as a signal of which class of product you're buying, not as the cost of moving it.
45dB and 50dB, Both Under Load
These are fan-noise-under-load ratings, and 5dB between them is a narrow gap next to how differently the two get used: the Apex's fans run in whatever room you set it down in, the EP900's run wherever it was installed. Neither figure tells you what either does at a 40W trickle in the small hours, which is the number a CPAP user actually wants.
Five Years Against Ten
Per dollar the Apex is covered 2.7 times better, and that ratio is mostly a statement about the Apex being cheap. In absolute terms BLUETTI backs the Apex stack for 5 of its 9.6 rated daily-use years and the EP900 for 10 of its 16.4. The longer term is worth more than the ratio suggests when the covered device is wired into a wall instead of sitting on a shelf.
Full record above — the Test Desk pick is the Apex 300 + B300K.
Check Apex 300 + B300K price →or check the EP900 + 3×B500 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 Apex 300 + B300K wins on both sticker price and long-term value. At $0.08/kWh over its lifetime, it's meaningfully cheaper to own. Clear value winner. One thing to know reading the table: both carry the same 6,000-cycle rating, so the lifetime rows are sticker price and capacity in disguise — the wear horizon is identical and decides nothing here.
Growth path
Apex 300 + 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 2,400W of solar. Enough for a serious multi-panel array.
Generous port selection supports complex multi-device setups.
Expansion batteries are BLUETTI-specific. You're investing in the BLUETTI ecosystem.
EP900 + 3×B500
EXPANDABLESupports BLUETTI expansion batteries, so you can add capacity later without replacing the base unit — useful if your needs may climb past 14,880Wh.
Accepts up to 9,000W of solar. Enough for a serious multi-panel array.
Limited ports. You'll likely need a power strip or splitter.
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, but the EP900 + 3×B500's higher solar ceiling (9,000W vs 2,400W) gives it the stronger off-grid growth path — more panels can feed a bigger bank as it grows.
What Owners Report
Patterns from published owner reports and long-term reviews — every claim cited to its source below.
BLUETTI Apex 300 + B300K
Field data on this combination is thin, and it's the reviewer kind rather than the owner kind: test units from mid-2025 into early 2026, no six-month reportsA4A12. What the reviews do give you is one genuinely useful datapoint. A tester in Australia ran a washing machine cycle and watched the Apex drop from 100% to 65% in about an hour, then added a heat-pump dryer and took it to 20% over the next hour and a halfA9A10. That's 80% of 5,529.6Wh on two loads of laundry, which conveys the scale better than any runtime chart.
Recharge impressed the same crowd. One reviewer had the system full again in under an hourA12, and another described it as the rare unit that could stand in for a generator without the noise or the fumesA4. On weight, the reviews and the spec sheet agree, which is unusual: two independent testers put the stacked system near 150 pounds and call it too much for one person to carryA5A14.
“The Apex 300 doesn't have USB ports, DC ports, or much of anything beyond its six AC plugs and high-voltage connectors.”
Sources
thesolarlab.com · techspective.net · digitalreviews.net · thesolarpit.com · cleantechnica.com · trustedreviews.com
BLUETTI EP900 + 3×B500
There is essentially no long-horizon owner data for the EP900 with three B500s. What exists is forum discussion by people deciding rather than people living with itB1B2B10. The hardware commentary that does exist is positive and specific: a cleaner cable system between the batteries than older BLUETTI gear, and a heavy-duty DC disconnect instead of a switch, which is the sort of detail an installer noticesB4B9.
Support is the recurring worry and it deserves a careful reading. The loudest complaints are about BLUETTI generally rather than this productB11B12, while the one person in the thread who has actually used the ESS support line reports a direct number and a firmware issue resolved by email inside a dayB3. Two forum members are also skeptical about the outdoor enclosure in real heat or a long solar-less cold stretch, and about how much the system consumes just sitting idleB6B7. Both are open questions rather than findings.
“on paper it's a dream but who knows with Bluetti tech support?”
Sources
diysolarforum.com · lifenhancer.com · bluettipower.worthepenny.co · trustpilot.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 flag that the base Apex 300 has no USB/DC ports and requires a separate paid Hub D1 accessory, which some feel is overpriced for what it offers. [Apex 300 + B300K · 3 entries]
- Multiple sources note the extreme weight/bulk of the stacked Apex 300 + B300K system, making 'portable' a stretch despite handles/trolley options. [Apex 300 + B300K · 2 entries]
- Reviewers praise fast recharge and the system's ability to genuinely replace a generator for home backup and heavy loads like washers/dryers. [Apex 300 + B300K · 4 entries]
- Prospective buyers repeatedly cite fear of poor Bluetti customer service/support as a deciding concern before purchase, and general Bluetti-brand reviews (not EP900-specific) corroborate slow or unhelpful support experiences. [EP900 + 3×B500 · 4 entries]
- Owners/installers praise the physical build quality improvements over older Bluetti units — cleaner cable management and a heavy-duty DC disconnect instead of a simple switch. [EP900 + 3×B500 · 2 entries]
- Skepticism exists about outdoor-enclosure durability claims in extreme heat/cold and about the unit's own parasitic power consumption, though this comes from forum speculation rather than confirmed field testing. [EP900 + 3×B500 · 2 entries]
- A4
“It's one of the few systems I've tested that feels like it could genuinely replace a generator, without the noise, fumes, or maintenance.”
techspective.net — Bluetti Apex 300 with B300K Review · 2025-09-21 · [positive]
- A5
“Stacked, you're near 150 pounds of lithium iron phosphate and inverter muscle—movable with the built-in handles or a trolley... but not something you'll casually lug to a picnic.”
techspective.net — Bluetti Apex 300 with B300K Review · 2025-09-21 · [mixed]
- A9
“Results: 1 wash took about 1 hour and drained the Apex from 100% down to 65%.”
digitalreviews.net — Bluetti Apex 300 Power Station Tests (Australia) Part II · 2025-09 · [positive]
- A10
“Just for fun we then turned on our heat pump dryer to see that over 1½ hours it would further drain it down to 20%.”
digitalreviews.net — Bluetti Apex 300 Power Station Tests (Australia) Part II · 2025-09 · [mixed]
- A12
“During my testing, the recharge speed was astonishing. In under an hour, I had a system ready to go again.”
thesolarpit.com — Bluetti Apex 300 Review · 2025-10-28 · [positive]
- A13
“For van lifers, the Apex 300 is a great base station, and the ability to add another 2.7kWh of capacity by simply purchasing another B300K expansion pack is a game-changer.”
cleantechnica.com — The Bluetti Apex 300 & B300K Portable Power Station Tested · 2025-08-05 · [positive]
- A14
“As will you: it weighs in at 38kg, and is probably much too big and heavy for most people to carry alone.”
trustedreviews.com — Bluetti Apex 300 Review · 2025-10-10 · [negative]
- B1
“on paper it's a dream but who knows with Bluetti tech support?”
diysolarforum.com — Bluetti EP900 thread · 2023-04 · [mixed]
- B2
“We are looking into adding a home battery backup, specifically the EP900 with 3 B500 batteries. The cost seems really competitive, but I'm concerned about some very negative customer service reviews.”
diysolarforum.com — Bluetti EP900 thread · 2023-04 · [mixed]
- B3
“customer service for EP800/900 ESS can be reached directly through this number... Their email support is also very responsive, and last time it took less than 24 hours to resolve a firmware issue with my AC500.”
diysolarforum.com — Bluetti EP900 thread · 2023-04 · [positive]
- B4
“Nice that Bluetti finally came up with a battery cable system between it's batteries that isn't a giant bulky obtrusive cable sticking a foot out.”
diysolarforum.com — Bluetti EP900 to Power your House thread · 2023-04 · [positive]
- B6
“Sunshine on it, it'll get hot... if you need to use it in real heat, or real cold for a string of near solar-less winter days I wouldn't count on it if it's installed outside.”
diysolarforum.com — Bluetti EP900 to Power your House thread · 2023-04 · [negative]
- B7
“Imho, Bluetti marketing is quite unrealistic. I wonder what the units consume themselves.”
diysolarforum.com — Bluetti EP900 to Power your House thread · 2023-04 · [negative]
- B9
“I really like that there's a heavy-duty DC disconnect on these units rather than a button or switch. This will be much more reliable long term.”
lifenhancer.com — Bluetti EP900 Review · 2025-03 · [positive]
- B10
“Bought the EP900 + 3×B500 for our home in Costa Rica.”
lifenhancer.com — Bluetti EP900 Review (reader comment referenced in review) · 2025-03 · [positive]
- B11
“I've had one of the worst experiences with customer service ever. My power station stopped charging, and since it was still under warranty, I reached out to the company.”
bluettipower.worthepenny.com — Bluetti Power customer review aggregator · unknown · [negative]
- B12
“Customer service is difficult to reach, only via a chat app on the website, and they are unable to assist you further.”
trustpilot.com — Bluetti reviews · 2025 (approx.) · [negative]
Research compiled August 9, 2026.
Who Should Buy Which
Buy the Apex 300 + B300K if you…
- →You want serious backup without hiring anyone. $2,599, plug it in, and 4,700Wh usable with 3,840W continuous handles the eight-hour outage modelled here with 3,055Wh still in reserve.
- →You rent, or you might move within the decade. Only one of these two systems comes with you.
- →Your van or trailer draw sits comfortably under the 4,685Wh a day modelled for full-time van life, and you'd rather keep the $11,199.
- →You want room to grow without redesigning anything: a second B300K adds about 2.7kWhA13 to what you already own.
Buy the EP900 + 3×B500 if you…
- →You're tying a battery into your service panel and you have, or intend to have, an array bigger than 2,400W. The 9,000W solar ceiling is the reason this system exists.
- →Your real daily draw exceeds what 4,700Wh usable can cover, day after day, year-round. 12,648Wh usable turns that 4,685Wh day into a 37% day.
- →You want the longest coverage available on a device you can't unbox and ship back: 10 years against 5.
- →Multi-day outages are normal where you live, and a second night without grid power is a planning assumption rather than bad luck.
If neither fits
If you want something you can carry, close the tab: the lighter of these two is 148.8 lbs across two boxes and the heavier one is a fixture. And if the actual job is a CPAP and a phone, that's 320Wh a night, 7% of the Apex. You'd be buying $2,599 of battery to use a fourteenth of it. A 1kWh-class portable does that job and fits on a nightstand.
The Bottom Line
Take the Apex 300 + B300K. $2,599 buys 4,700Wh of usable energy that covers every load on this page, at 13 cents per lifetime kilowatt-hour against the EP900's 15, and it does all of it from a wall outlet. The single place it genuinely runs out, a 4,685Wh day with 15Wh to spare, is an argument for a second B300K rather than for spending $11,199 more.
The EP900 + 3×B500 is the better machine, and that was never in dispute. It's also a fixture: 466 lbs of inverter and battery modules that does nothing at all until someone connects it to your service. If that install is the project you're actually doing, buy it and don't feel overcharged. If it isn't, everything it beats the Apex at is something you'd own and never touch.
Frequently Asked Questions
Answers drawn from the spec record and cited owner research.
Is the EP900 worth five times the price of the Apex 300?
Only if you're installing it. At $13,798 against $2,599 you're paying about 93 cents per watt-hour instead of 47, and what you get for it is 12,648Wh of usable storage, 9,000W of output and a 9,000W solar ceiling. Those are whole-home numbers and they're priced fairly. They're also unreachable until the system is wired into your panel, so if that isn't the plan, the answer is no.
Can the Apex 300 + B300K back up a whole house?
It backs up whatever you can plug into it, up to 3,840W continuous with 7,680W of surge headroom for motor startup. That's a large slice of a house but it isn't the house. Panel-level backup is what the EP900's 9,000W is for. If your must-run list fits on extension cords, the Apex gets you there for $11,199 less.
How long will each one last?
The Apex stack is rated for 3,500 cycles and the EP900 for 6,000, which at one full cycle a day works out to 9.6 and 16.4 years. Cycle twice a week instead and both outlive any sane ownership window, 33.7 years and 57.7. Reaching the cycle rating doesn't kill either battery either; it means roughly 80% of the original capacity is left.
Which one should I get for van life?
The Apex, and only if your daily draw sits well under 4,685Wh. That's the figure modelled for full-time van life, and the Apex's 4,700Wh of usable energy clears it by 15Wh, which is not a margin. The EP900 wins that scenario on paper and can't be considered in practice: 466 lbs across four chassis, wired into a building. If your draw really is that high, price a second B300K before anything else.
What can 5,529.6Wh actually run?
One reviewer's laundry day gives the clearest picture: a wash cycle took the Apex from 100% to 65% in about an hour, and a heat-pump dryer took it from 65% to 20% over the following hour and a half. That's 80% of the pack on two appliances nobody thinks of as exotic. Ordinary loads look completely different, which is why the eight-hour blackout modelled here uses 1,645Wh and leaves 3,055Wh untouched.
Where to buy
BLUETTI Apex 300 + B300KPick
$2,599.00
$2,599.00 · direct from BLUETTI
Last checked 1 day ago. Prices move — check before you buy.
BLUETTI EP900 + 3×B500
$13,798.00
$13,798.00 · direct from BLUETTI
Last checked 1 day ago. Prices move — check before you buy.
Prices may vary by retailer and are subject to change.