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89.7″ · 2,278 mm
44.6″ · 1,134 mm wide · 1.38″ (35 mm) frame · 61.7 lb (28 kg)
Solar panelAXITEC

AXITEC AC-550MBT/144V

144 half-cut cells, bifacial, composite film, cell spaces transparent. Power classes 530–555 W in the CEC list.

CEC listed · Oct 3, 2022UL 61730Bifacial · 70 ± 10%15-yr product + 25-yr performance warranty
Power class
  • Power (STC)550 WCEC nameplate
  • Efficiency≥21.3%datasheet minimum
  • %/°C Pmax−0.35CEC test: −0.372
  • Performance warranty25 yrdatasheet

Power classes

CEC PV Module List (Oct 7, 2026) · AXITEC datasheet · 6 models
ModelPmaxVoc, VIsc, AVmp, VImp, AEfficiencyPTCCEC listed
AC-530MBT/144V530 W49.3013.7241.3112.83≥20.5%495 WOct 3, 2022
AC-535MBT/144V535 W49.4513.7941.4712.90≥20.7%500 WOct 3, 2022
AC-540MBT/144V540 W49.6013.8641.6412.97≥20.9%505 WOct 3, 2022
AC-545MBT/144V545 W49.7513.9341.8013.04≥21.1%510 WOct 3, 2022
AC-550MBT/144V550 W49.9014.0041.9613.11≥21.3%515 WOct 3, 2022
AC-555MBT/144V555 W50.0514.0742.1113.18≥21.5%520 WOct 3, 2022

Build & dimensions

AXITEC datasheets · Cali-Graf calculation

Heat & cold behaviour

AXITEC datasheet · CEC PV Module List (Oct 7, 2026) · Cali-Graf calculation
DatasheetCEC listing test
Pmax coefficient γ−0.35 %/°C−0.372 %/°C
Voc coefficient β−0.29 %/°C−0.287 %/°C
Isc coefficient α+0.05 %/°C+0.038 %/°C
Vmp coefficient≈ −0.40 %/°C—
Operating cell temperatureNMOT 45 °CNOCT 43.4 °C
Vmp coefficient ≈ γ − α (datasheet); used only for the hot-roof voltage estimate.

Away from lab conditions — CEC listing test points

ClassPmax at NOCTVmp × Imp at NOCTPmax at 200 W/m²Low-light efficiency vs STC
530 W405.7 W39.11 V × 10.37 A102 W96%
535 W409.5 W39.26 V × 10.43 A102.9 W96%
540 W413.4 W39.42 V × 10.49 A103.9 W96%
545 W417.3 W39.57 V × 10.54 A104.9 W96%
550 W421.1 W39.73 V × 10.6 A105.8 W96%
555 W424.9 W39.87 V × 10.66 A106.8 W96%
Pmax = Vmp × Imp from the CEC listing; low-light efficiency = Pmax at 200 W/m² ÷ (20% of STC Pmax).

Electrical & strength ratings

AXITEC datasheet
Packaging: 31 per pallet

Bifacial performance

NLR SAM module library · AXITEC datasheet
Rear gain depends on mounting height and ground reflectance; flush roof mounts receive little rear light.

Certifications

CEC PV Module List (Oct 7, 2026) · AXITEC datasheet
UL 61730UL 1703IEC 61730Fire rating Type 1 (UL 61730)

Warranty & degradation

AXITEC datasheet

Inverter compatibility & string sizing

AXITEC datasheet · Cali-Graf calculation · NLR PVWatts v8 · CEC PV Module List (Oct 7, 2026) · inverter datasheets · NLR SAM inverter library · CEC Grid Support Inverter List (Oct 7, 2026)
53.2 V
Voc when cold
per panel
33.8 V
Vmp when hot
per panel
11
Max panels / string
max DC 600 V
2
Min panels / string
MPPT from 60 V
Defaults come from NLR TMY weather (coldest hour, hottest modeled cell). Code calculations (NEC 690.7) use the ASHRAE extreme annual minimum, which is usually colder — enter it above.

String inverters most named in SoCal permits

InverterMax DC inputMPPTWindow sourcePanels per string
Tesla 1538000-xx-y600 V60–480 Vdatasheet2–11
Solis (Ginlong) S6-EH1P10K-H-US600 V80–520 Vdatasheet3–11
Solis (Ginlong) Solis-1P7.6K-4G-US600 V100–500 Vdatasheet3–11
Qcells Q.VOLT H7.6SX498 V234–498 VCEC test window7–9

Microinverters (one per panel)

MicroinverterRecommended module powerMax DC inputMPPTVoc cold / Vmp hotCheckDC/AC
APsystems (Alt Power System) DS3-L265–570 W60 V28–45 V53.2 / 33.8 V✓ Within range0.71
Voltage check against the microinverter datasheets — confirm the pairing on the manufacturer’s module compatibility list. Rows appear only when the panel’s power is inside the microinverter’s recommended module power range.
SolarEdge and other optimizer-based systems size strings by the optimizer rules — use the manufacturer’s designer. Reference inverters: most named in SoCal permits since Oct 2024.

Expected production in Southern California

NLR PVWatts v8 · Cali-Graf calculation
CitykWh / kW / yrkWh / panel / yrkWh / system / yrSun, kWh/m²/day
Los Angeles1,67692211,9836.08
Palmdale1,8351,00913,1206.69
Chula Vista1,69693312,1266.11
Huntington Beach1,64390411,7475.89
Riverside1,69693312,1266.21
Santa Clarita1,72494812,3276.28
782Jan783Feb1,005Mar1,110Apr1,096May1,165Jun1,227Jul1,241Aug1,085Sep957Oct823Nov712DeckWh per month · Los Angeles
Estimate for comparison, not a quote: shading, roof orientation and local losses change real output. Roof mount, 20° tilt, south, 14% system losses.

Compare with similar 550 W panels

CEC PV Module List (Oct 7, 2026) · Kiwa PVEL Scorecard · datasheets · building permits
PanelPmaxEfficiencyγ Pmax (CEC)Voc, VIsc, ASizePVEL (product / brand)SoCal permits (series)
AXITEC AC-550MBT/144V550 W≥21.3%−0.37249.91489.7 × 44.6 in——
JA Solar JAM72D30-550/MB550 W≈21.8%−0.33049.914—product 2023, 20243
LONGi LR5-72HBD-550M550 W≥21.5%−0.35449.813.9988.8 × 44.6 inproduct 20261
Canadian Solar CS6W-550MB-AG550 W≈21.4%−0.32449.61489.2 × 44.6 inproduct 20241
Same fields from the same sources for every row; ≈ efficiency is calculated from the listed area. Comparable series: other brands, same product group, power range covering this class.

Documents

manufacturer documents

Questions & answers

How efficient is the AXITEC AC-550MBT/144V?

The AXITEC datasheet guarantees at least 21.3% module efficiency for the 550 W class (up to 21.5% for 555 W). 550 W over 2.58 m² equals about 213 W per square meter.

How much energy does one panel produce in Los Angeles or Palmdale?

PVWatts v8 with typical-year weather gives about 922 kWh per year per 550 W panel in Los Angeles and about 1,009 kWh in Palmdale (20° roof, facing south, 14% system losses).

How much power does it lose on a hot roof?

With γ = −0.35 %/°C, at a 77 °C cell temperature (hottest modeled hour in Palmdale) output is about 18.1% below the STC rating.

How many panels fit on one string?

With the Tesla 1538000-xx-y (max DC 600 V, MPPT from 60 V, datasheet) in Los Angeles the calculator gives 2–11 panels per string (Voc at 2 °C = 53.2 V, Vmp at 74 °C cell = 33.8 V). Final design must follow the inverter manual and NEC 690.7.

Does it work with APsystems (Alt Power System) DS3-L microinverters?

Voltage check against the APsystems (Alt Power System) datasheet: Voc when cold 53.2 V vs max input 60 V; Vmp when hot 33.8 V vs MPPT low 28 V; recommended module power 265–570 W. Confirm on the microinverter maker’s compatibility list.

What does the warranty cover?

15 years on the product and 25 years on performance (manufacturer datasheet).

How big and heavy is it?

89.7 × 44.6 × 1.38 in (2,278 × 1,134 × 35 mm), 61.7 lb (28 kg).

Is it bifacial?

Yes, bifaciality 70 ± 10%. Rear gain depends on mounting height and ground reflectance.

Sources

  1. California Energy Commission — Solar Equipment Lists, PV Module List, Inverter List (snapshot Oct 7, 2026).
  2. AXITEC — datasheet AXIworldbipremium bifacial 144 cells asemmbled in US.
  3. AXITEC — datasheet AXIworldbipremium bifacial 144 cells.
  4. LONGi — manufacturer datasheet “LR5-72HBD Suitable for distributed projects Advanced module technology delivers superior”.
  5. Canadian Solar — datasheet BiHiKu6 BIFACIAL MONO PERC CS6W-520|525|530|535|540|545|550MB-AG.
  6. AXITEC — document library on the manufacturer’s website (links above).
  7. Kiwa PVEL — PV Module Reliability Scorecard, Top Performer lists.
  8. NLR (formerly NREL) — System Advisor Model CEC module and inverter libraries (version 2026.7.3).
  9. NLR (formerly NREL) — PVWatts v8, NSRDB PSM v3 typical-year weather for Los Angeles, Palmdale, Chula Vista, Huntington Beach, Riverside, Santa Clarita.
  10. Inverter datasheets — APsystems (Alt Power System), Solis (Ginlong), Tesla (manufacturer documents).
  11. Building permits — Southern California permit portals. Equipment matched from permit descriptions.
  12. Cali-Graf calculations — formulas and inputs are shown next to each calculated value (efficiency from area, temperature-corrected voltages, string sizing, energy estimates).