Tesla Powerwall 3 vs. Enphase IQ Battery 5P vs. FranklinWH aPower 2
Last verified 2026-09-05. Figures carry their sources at the foot of this page.
A Tesla Powerwall 3 holds 13.5 kWh and can be field-configured to push out up to 11.5 kW continuous. An Enphase IQ Battery 5P holds 5.0 kWh usable and tops out at 3.84 kVA. A FranklinWH aPower 2 holds 15 kWh and delivers 10 kW continuous, 15 kW for ten-second bursts. Those three numbers alone tell you these aren't interchangeable boxes competing on the same spec — they're three different bets about how a home battery should be built and sold.
Tesla bundles a hybrid solar inverter into the battery itself. Enphase builds the battery out of six small grid-forming microinverters with no single point of failure. FranklinWH builds a big single unit that couples to any existing solar inverter through a separate controller. Each approach has a real, mechanical reason to prefer it for a specific house — and a real reason to avoid it for a different one.
This page compares the three on capacity, output, coupling architecture, scalability, warranty terms, and what installer-network reality looks like in California right now, including what happens to your battery's warranty when the company that installed it goes bankrupt — which, as of September 2026, is not a hypothetical.
Three different architectures, not three flavors of the same thing
Tesla Powerwall 3 is fundamentally a DC-coupled all-in-one unit: it has an integrated hybrid inverter with six MPPTs and up to 20 kW of DC solar input built into the same box as the battery. That's the standard configuration for a new solar-plus-storage install. But Powerwall 3 can also run AC-coupled to an existing separate solar inverter through Tesla's Backup Gateway 2, which supports up to 10 AC-coupled Powerwalls — in that mode the Powerwall becomes its own site controller and the Gateway's controller function switches off. It is genuinely both, depending on how the installer configures it, and any comparison that flattens it to just "DC-coupled" or just "AC-coupled" is oversimplifying.
Enphase IQ Battery 5P is 100% AC-coupled by design, with no DC input and no MPPTs on the unit itself. What makes it structurally different from the other two is that it isn't a single battery with one inverter — it's six embedded IQ8D-BAT grid-forming microinverters working in parallel inside one enclosure. There's no single point of failure the way a Powerwall's or aPower's central inverter represents. It also retrofits cleanly onto an existing Enphase microinverter solar array, which the other two can't do without an AC-coupling adapter.
FranklinWH aPower 2 is AC-coupled and inverter-agnostic — it pairs with any existing solar inverter, which makes it the most flexible retrofit option of the three for a house that already has panels from any manufacturer. It requires FranklinWH's aGate controller to function as a full energy-management system across solar, grid, generator, and EV — that's a mandatory add-on, not an option, and it adds real cost.
Capacity, output, and what that means at the breaker panel
Powerwall 3's output is field-selectable at install: 5.8 kW, 7.6 kW, 10 kW, or 11.5 kW continuous AC, with max apparent power to 11,500 VA at the top setting. Off-grid, PV-only discharge can reach 15.4 kW, but only if the on-grid setting is locked to 11.5 kW and the installer runs an 80A breaker with sized conductors — a detail that matters for panel-capacity planning and should be discussed with your installer before assuming you'll get that number. Load-start capability is 185 LRA, enough to start most single AC compressors without a soft-starter.
Enphase's 5P delivers 3.84 kVA continuous at 240V (3.33 kVA at 208V), with a 3-second peak to roughly 7.68 kVA and 48A LRA start capability. Because each unit is only 5.0 kWh, whole-home backup on a typical California house means stacking three or four units — which raises labor and wiring cost per kWh delivered compared to a single larger box, even though the hardware itself scales cleanly.
FranklinWH's aPower 2 delivers 10 kW continuous and 15 kW peak for 10 seconds, with 8 kW continuous charge power — the highest continuous output per single unit of the three. For a house with a well pump, HVAC compressor, and other simultaneous heavy loads during an outage, that per-unit headroom is a real advantage over needing multiple smaller units to hit the same instantaneous draw.
Scalability: how big can each system actually get
Tesla caps a single system at 4 Powerwall 3 units (each with its own inverter) plus up to 3 Expansion units (battery-only, no inverter, floor-mount only, not field-serviceable individually, and compatible only with Powerwall 3 — not with older Powerwall 2 or Powerwall+). That's 7 total units, 94.5 kWh, and per Tesla's own marketing copy, up to 44 kW combined output at the top end.
Enphase's ceiling depends on the controller: up to 4 IQ Battery 5P units (20 kWh) on an IQ System Controller 3G without a power control system, or up to 8 units (40 kWh) on an IQ System Controller 3 with PCS enabled. Some secondary sources claim a 16-unit, 80 kWh ceiling — that contradicts Enphase's own support-page FAQ and shouldn't be relied on; treat 40 kWh as the real ceiling until Enphase publishes otherwise.
FranklinWH scales the furthest on paper: up to 15 aPower 2 units per aGate controller, 225 kWh total — but only on standard 120/240V split-phase residential service. On 208V service (relevant for some California multi-family and ADU-adjacent properties), the datasheet caps it at 2 units per aGate. If your property runs 208V, confirm this with your installer before assuming the 225 kWh figure applies.
Warranty terms: read past the headline year count
Tesla's Powerwall 3 warranty is 10 years, with 70% capacity retention guaranteed at that point and unlimited cycles for self-consumption, time-based control, and backup use. Other use cases are capped at 37.8 MWh aggregate throughput. Tesla's warranty documentation reportedly ties full 10-year coverage to the Powerwall staying connected to the internet for firmware updates, with coverage potentially reduced if connectivity lapses for an extended period — we could not independently confirm the exact trigger or reduced term directly on Tesla's warranty PDF (blocked by bot protection during this research), so treat this as a documented but unverified detail worth asking your installer to confirm in writing before you sign.
Enphase's IQ Battery 5P carries a 15-year warranty (or 6,000 cycles, whichever comes first) with over 60% capacity retention guaranteed. At roughly one cycle per day, 6,000 cycles works out to about 16.4 years — so the cycle cap and the term roughly align for a typical daily-cycling household, but a heavy user pulling multiple cycles a day could hit the cycle ceiling before the 15-year clock runs out.
FranklinWH's aPower 2 carries a 15-year warranty tied to a 60 MWh aggregate throughput cap, matching Enphase's term length and beating Tesla's 10-year headline number. What FranklinWH does not publish, as of this research, is a stated capacity-retention percentage at the end of that term — Tesla commits to 70% at 10 years, Enphase to over 60% at 15 years, and FranklinWH has not published a comparable number in its datasheet or in any verified secondary source. That's a real gap in what the company discloses, not a knock on the hardware — but don't let anyone tell you FranklinWH matches the other two on this point until they publish a number.
App, monitoring, and the installer-bankruptcy problem nobody puts in the brochure
Enphase's datasheet is the only one of the three that explicitly calls out open API integration alongside its Installer Platform and consumer app — relevant if you want a system that talks to third-party home-energy software. Tesla and FranklinWH each offer only their own proprietary mobile app, with no API integration claim in either datasheet.
Here's the part that matters more than any app screenshot: California has already lost two major installers this year. Freedom Forever filed Chapter 11 on April 15, 2026 in the U.S. Bankruptcy Court for the District of Delaware. After a proposed sale to company insiders fell through, it asked the court on July 31, 2026 to convert the case to Chapter 7 liquidation, and the judge signed that order on August 7, 2026 — the company no longer operates. Freedom Forever had completed roughly 150,000 residential installations nationally since 2011, per its own reported history and multiple outlets covering the case; that's a lifetime install count, not a confirmed tally of how many customers are actively affected by the shutdown, and no court filing we found breaks that number out. If Freedom Forever installed your battery, the safe assumption is that you need to check your paperwork regardless. Sunnova filed Chapter 11 in June 2025; its legacy portfolio is now administered by SunStrong, which is not originating new contracts. If either company installed your battery, the manufacturer's warranty on the hardware itself — Tesla, Enphase, or FranklinWH, all backed directly by the manufacturer, not the installer — should still hold. What does not survive is any separate workmanship warranty your now-defunct installer wrote on top of it. Ask any installer you're considering, in writing, what happens to your workmanship coverage if they close.
We found no verified, primary-sourced data this research cycle on installer-network size or market share for any of the three brands in California — claims of specific percentages circulating online trace to low-authority SEO content, not manufacturer or industry data, and we're not repeating them here.
Which battery fits which house
A new-build solar-plus-storage install with no existing panels is Powerwall 3's best case — the integrated hybrid inverter removes a design step and reduces installer complexity, and its per-unit output (up to 11.5 kW configurable) covers most whole-home backup needs with one or two units.
A house that already has an Enphase microinverter solar array is the clearest fit for the IQ Battery 5P — it retrofits without an AC-coupling adapter, and the distributed six-microinverter architecture means no single component failure takes the whole battery offline. It's the right call for a smaller, space-constrained install or a homeowner who wants precise control over exactly how much capacity to add, unit by 5.0 kWh unit.
A house with high simultaneous loads during an outage — a well pump plus HVAC compressor plus other heavy draws at once — and an existing non-Enphase solar inverter is the strongest case for FranklinWH's aPower 2, given its 10 kW continuous / 15 kW peak per-unit output and inverter-agnostic AC coupling. Its OSHPD seismic certification (AC 156 / OSHPD / IEEE 693-2005 high, per the aPower 2 datasheet's compliance table — the same standard used for California hospital facilities) is also a notable, if underreported, compliance data point for anyone weighing CA-specific installation standards. The tradeoff: the mandatory aGate controller adds cost, and the unit itself is the largest and heaviest of the three at 357 lb.
Head-to-head spec comparison, per manufacturer datasheet (Tesla energylibrary.tesla.com 2025; Enphase DSH-00010-11.0-EN 2025-05-06; FranklinWH aPower 2 datasheet, nameplate model aPower X-20, franklinwh.com, rev. 2025-12-16)
| Spec | Tesla Powerwall 3 | Enphase IQ Battery 5P | FranklinWH aPower 2 |
|---|---|---|---|
| Usable capacity per unit | 13.5 kWh | 5.0 kWh | 15 kWh |
| Continuous output | 5.8 / 7.6 / 10 / 11.5 kW (field-selectable) | 3.84 kVA @240V | 10 kW |
| Peak output | Up to 11,500 VA | ~7.68 kVA (3-sec) | 15 kW (10-sec) |
| Coupling | Integrated hybrid inverter (DC), or AC-coupled via Backup Gateway 2 | 100% AC-coupled, 6 embedded microinverters | AC-coupled, any existing inverter |
| Max system size | 7 units (4 PW3 + 3 Expansion), 94.5 kWh | 8 units w/ PCS controller, 40 kWh | 15 units per aGate, 225 kWh (120/240V only) |
| Warranty term | 10 years | 15 years or 6,000 cycles | 15 years, 60 MWh throughput cap |
| Capacity retention guarantee | 70% at 10 years | Over 60% at 15 years | Not published |
| Weight (single unit) | 291 lb | 174 lb | 357 lb |
| Required companion hardware | Backup Gateway 2 (for AC-coupled mode) | IQ Combiner / System Controller | aGate controller (mandatory) |
| Installed price range (installer-quoted estimates, not manufacturer list price) | $12,000-$16,500 single unit | $6,000-$10,000 single unit | $15,000-$20,000 incl. aGate |
When this is the wrong move
Skip all three, at least on a cash or loan purchase, if you're buying storage purely to chase a federal tax credit — Section 25D ended December 31, 2025, with no phase-down, and it applies equally to every brand here. None of these batteries restores that credit.
Skip SGIP as a reason to move fast. As of this research (selfgenca.com, checked 2026-09-05), General Market, Small Residential, Equity Resiliency, Non-Residential Storage, and the San Joaquin Valley residential budget are all closed to new standard applicants. The only live path is the income-qualified AB 209 track within Residential Solar and Storage Equity, and even there just the publicly-owned-utility (POU) segment shows Open status — the rest of that same track is waitlist or closed. That's a narrow exception, not a reason to rush.
Skip Enphase's 5P if your home needs more than 40 kWh of backup or draws heavy simultaneous loads — you'll need so many units that labor cost per kWh delivered gets worse than a single larger box, and the per-unit continuous output (3.84 kVA) won't start large single loads without stacking units.
Skip FranklinWH if your service is 208V and you were counting on the 225 kWh scaling figure — the datasheet caps 208V installs at 2 units per aGate, a very different ceiling.
Skip any of these if you're on a publicly owned utility (LADWP, SMUD, MID, Anaheim, Roseville, Lodi, Imperial ID, Turlock ID) and were told NEM 3.0 export-rate pressure makes a battery urgent — those utilities set their own net-metering terms and aren't subject to CPUC NEM 3.0, so the urgency argument that applies to PG&E, SCE, and SDG&E customers doesn't automatically apply to you.
Frequently asked questions
Which of these three batteries has the longest warranty?
Enphase's IQ Battery 5P and FranklinWH's aPower 2 both carry 15-year warranties, longer than Tesla Powerwall 3's 10-year term. But term length isn't the whole story: Enphase guarantees over 60% capacity retention at 15 years, Tesla guarantees 70% at 10 years, and FranklinWH has not published a capacity-retention percentage for its 15-year term in its datasheet or in any verified secondary source as of this writing. A longer term with an unpublished retention guarantee isn't automatically the stronger warranty — ask FranklinWH's installer directly for that number in writing before you compare it head to head with the other two.
Can I get a federal tax credit for any of these batteries in 2026?
Not on a cash or loan purchase. The Section 25D Residential Clean Energy Credit, which gave homeowners 30% back on battery storage, was repealed by the One Big Beautiful Bill Act and ended for property placed in service after December 31, 2025 — nine years ahead of its original 2034 sunset, with no phase-down. This applies identically to Tesla, Enphase, and FranklinWH. The only remaining route to any ITC-equivalent value in 2026 is third-party ownership (a lease or PPA), where the leasing company — not you — claims the separate Section 48E commercial credit and may or may not pass savings through in your lease rate.
Is SGIP still worth applying for with any of these batteries?
For nearly every California homeowner, no — as of September 5, 2026, per selfgenca.com's own program-metrics page, General Market, Small Residential Storage, Equity Resiliency, Non-Residential Storage Equity, and the San Joaquin Valley residential budget are all listed Closed to new standard applicants. The one live opening is narrower than it sounds: within the income-qualified Residential Solar and Storage Equity track, only the AB 209 segment for customers of publicly owned utilities (POU) shows Open status — the AB 209 non-POU segment and the ratepayer-funded segment are both Waitlist or Closed. If you're not an income-qualified POU customer in that specific track, don't factor SGIP into your budget.
What happens to my battery's warranty if my installer goes out of business?
The manufacturer's warranty on the battery itself — Tesla, Enphase, or FranklinWH, all backed directly by the manufacturer rather than the installer — should remain valid regardless of the installer's solvency. What doesn't survive is any separate workmanship warranty the installer wrote on top of it. This is directly relevant in 2026: Freedom Forever filed Chapter 11 on April 15, 2026 and was converted to Chapter 7 liquidation by court order on August 7, 2026, and Sunnova's legacy portfolio (Chapter 11, June 2025) is now run by SunStrong and not writing new contracts. If either company installed your system, get any workmanship-warranty status in writing from whoever services it now.
Which battery is easiest to add onto an existing solar system?
It depends on what you already have. If your existing array uses Enphase microinverters, the IQ Battery 5P retrofits without an AC-coupling adapter. FranklinWH's aPower 2 is the most inverter-agnostic option — it AC-couples to essentially any existing solar inverter, which makes it the most flexible retrofit for a mixed or unknown-brand array. Tesla Powerwall 3 can also be added AC-coupled to an existing separate inverter via Backup Gateway 2 (which supports up to 10 AC-coupled Powerwalls), but its integrated hybrid inverter is really built for new solar installs, not retrofits.
How much do these batteries actually cost installed in California?
None of the three manufacturers publishes consumer list pricing, so every number below comes from installer and industry blog estimates, not a manufacturer price sheet — treat these as directional ranges, not quotes. Powerwall 3 runs roughly $12,000-$16,500 installed for a single unit in California, with additional units around $10,000 each before incentives. Enphase's 5P shows a wide spread across sources, roughly $6,000-$10,000 installed per unit. FranklinWH's aPower 2, including the mandatory aGate controller, runs roughly $15,000-$20,000 installed. Get a written, itemized quote from your installer rather than budgeting off any of these ranges.
The bottom line
Powerwall 3 is the strongest default for a new solar-plus-storage build, with an integrated hybrid inverter and configurable output up to 11.5 kW continuous. Enphase's IQ Battery 5P is the clear pick if you already own Enphase microinverters or want distributed, no-single-point-of-failure architecture in a smaller footprint. FranklinWH's aPower 2 wins on raw per-unit output (10 kW continuous, 15 kW peak) and inverter-agnostic retrofitting, at the cost of a mandatory controller and no published capacity-retention number. None of the three restores the federal tax credit that expired December 31, 2025, and SGIP is closed to nearly every new California applicant — the one live opening is a narrow income-qualified track, not a regional exception. Get every pricing, warranty, and workmanship-coverage claim in writing before you sign — especially given how many installers have gone bankrupt in the past two years.
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Sources
Rates and incentive programs change. Each figure above traces to one of these.
- Tesla Powerwall 3 Datasheet — Powerwall 3 capacity, output, coupling, scalability, efficiency, warranty headline, dimensions
- Enphase IQ Battery 5P Data Sheet (DSH-00010-11.0-EN-2025-05-06) — IQ Battery 5P capacity, output, architecture, warranty, dimensions, API integration claim
- Enphase Support FAQ — IQ Battery 5P system scalability (4 units/20kWh without PCS, 8 units/40kWh with PCS)
- FranklinWH aPower 2 Datasheet (nameplate model aPower X-20, SKU APR-10K15V2-US, rev. 2025-12-16) — aPower 2 capacity, output, cycle life, warranty term, aGate requirement, and seismic (AC 156 / OSHPD / IEEE 693-2005) plus other compliance certifications
- SelfGenCA Program Metrics — SGIP program status by category including San Joaquin Valley (Closed) and the AB 209 POU segment (Open), checked 2026-09-05
- One Big Beautiful Bill Act / Section 25D repeal coverage — Federal residential battery/solar tax credit expiration December 31, 2025
- PV Magazine USA — Freedom Forever files Chapter 11 bankruptcy — Freedom Forever Chapter 11 filing date, April 15, 2026
- Law360 Bankruptcy Authority — Freedom Forever Ch. 7 Shift OK'd With Reporting Terms — Freedom Forever Chapter 7 conversion motion (July 31, 2026) and signed court order (August 7, 2026)
- IndexBox — Freedom Forever Bankruptcy: What 150,000 Solar Homeowners Need to Know — Freedom Forever lifetime installation count (~150,000), cited here as company history, not a confirmed count of bankruptcy-affected customers