132 half-cut cells, bifacial, white backsheet. Power classes 475–505 W in the CEC list.
| Model | Pmax | Voc, V | Isc, A | Vmp, V | Imp, A | Efficiency | PTC | CEC listed |
|---|---|---|---|---|---|---|---|---|
| HT66-18X-475 | 475 W | 44.80 | 13.58 | 37.26 | 12.64 | ≈20.0% | 439 W | Aug 11, 2021 |
| HT66-18X-475 {Clr} | 475 W | 44.80 | 13.58 | 37.26 | 12.64 | ≈20.0% | 438 W | Aug 11, 2021 |
| HT66-18X-480 | 480 W | 44.95 | 13.65 | 37.77 | 12.72 | ≈20.2% | 444 W | Aug 11, 2021 |
| HT66-18X-480 {Clr} | 480 W | 44.95 | 13.65 | 37.77 | 12.72 | ≈20.2% | 442 W | Aug 11, 2021 |
| HT66-18X-485 | 485 W | 45.10 | 13.73 | 37.92 | 12.80 | ≈20.4% | 449 W | Aug 11, 2021 |
| HT66-18X-485 {Clr} | 485 W | 45.10 | 13.73 | 37.92 | 12.80 | ≈20.4% | 447 W | Aug 11, 2021 |
| HT66-18X-490 | 490 W | 45.25 | 13.79 | 38.07 | 12.88 | ≈20.7% | 454 W | Aug 11, 2021 |
| HT66-18X-490 {Clr} | 490 W | 45.25 | 13.79 | 38.07 | 12.88 | ≈20.7% | 452 W | Aug 11, 2021 |
| HT66-18X-495 | 495 W | 45.40 | 13.86 | 38.22 | 12.96 | ≈20.9% | 458 W | Aug 11, 2021 |
| HT66-18X-495 {Clr} | 495 W | 45.40 | 13.86 | 38.22 | 12.96 | ≈20.9% | 457 W | Aug 11, 2021 |
| HT66-18X-500 | 500 W | 45.50 | 13.93 | 38.37 | 13.04 | ≈21.6% | 471 W | Aug 21, 2024 |
| HT66-18X-505 | 505 W | 45.70 | 13.99 | 38.52 | 13.12 | ≈21.9% | 476 W | Aug 21, 2024 |
| CEC listing test | |
|---|---|
| Pmax coefficient γ | −0.373 %/°C |
| Voc coefficient β | −0.255 %/°C |
| Isc coefficient α | +0.035 %/°C |
| Operating cell temperature | NOCT 45.9 °C |
| Class | Pmax at NOCT | Vmp × Imp at NOCT | Pmax at 200 W/m² | Low-light efficiency vs STC |
|---|---|---|---|---|
| 475 W | 339.1 W | 35.05 V × 9.67 A | 86.3 W | 91% |
| 475 W | 348.5 W | 35.28 V × 9.88 A | 88.4 W | 93% |
| 480 W | 345.9 W | 35.53 V × 9.74 A | 88 W | 92% |
| 480 W | 355.5 W | 35.77 V × 9.94 A | 90.2 W | 94% |
| 485 W | 349.5 W | 35.67 V × 9.8 A | 88.9 W | 92% |
| 485 W | 359.2 W | 35.91 V × 10 A | 91.1 W | 94% |
| 490 W | 353 W | 35.81 V × 9.86 A | 89.8 W | 92% |
| 490 W | 362.9 W | 36.05 V × 10.07 A | 92 W | 94% |
| 495 W | 356.6 W | 35.95 V × 9.92 A | 90.7 W | 92% |
| 495 W | 366.6 W | 36.19 V × 10.13 A | 92.9 W | 94% |
| 500 W | 367.6 W | 35.26 V × 10.43 A | 98.2 W | 98% |
| 505 W | 371.3 W | 35.39 V × 10.49 A | 99.2 W | 98% |
| Year | Product | Tests |
|---|---|---|
| 2024 | HT66-18X-xxx | DHHSSLID+LETIDPID |
| 2025 | HT66-18X-xxx | MSS |
| Inverter | Max DC input | MPPT | Window source | Panels per string |
|---|---|---|---|---|
| Tesla 1538000-xx-y | 600 V | 60–480 V | datasheet | 2–12 |
| Solis (Ginlong) S6-EH1P10K-H-US | 600 V | 80–520 V | datasheet | 3–12 |
| Solis (Ginlong) Solis-1P7.6K-4G-US | 600 V | 100–500 V | datasheet | 4–12 |
| Qcells Q.VOLT H7.6SX | 498 V | 234–498 V | CEC test window | 8–10 |
| Microinverter | Recommended module power | Max DC input | MPPT | Voc cold / Vmp hot | Check | DC/AC |
|---|---|---|---|---|---|---|
| Enphase IQ8X-80-M-US | 320–540 W | 79.5 V | 43–60 V | 47.7 / 30.3 V | ✗ Not a match: module voltage below MPPT range | 1.28 |
| APsystems (Alt Power System) DS3-L | 265–570 W | 60 V | 28–45 V | 47.7 / 30.3 V | ✓ Within range | 0.62 |
| Enphase IQ8A-72-2-US | 295–500 W | 60 V | 32–45 V | 47.7 / 30.3 V | ⚠ Works; below MPPT at peak heat | 1.39 |
| City | kWh / kW / yr | kWh / panel / yr | kWh / system / yr | Sun, kWh/m²/day |
|---|---|---|---|---|
| Los Angeles | 1,676 | 813 | 11,380 | 6.08 |
| Palmdale | 1,835 | 890 | 12,460 | 6.69 |
| Chula Vista | 1,696 | 823 | 11,516 | 6.11 |
| Huntington Beach | 1,643 | 797 | 11,156 | 5.89 |
| Riverside | 1,696 | 823 | 11,516 | 6.21 |
| Santa Clarita | 1,724 | 836 | 11,706 | 6.28 |
| Panel | Pmax | Efficiency | γ Pmax (CEC) | Voc, V | Isc, A | PVEL (product / brand) | SoCal permits (series) |
|---|---|---|---|---|---|---|---|
| Shanghai Aerospace Automobile Electromechanical HT66-18X 485 | 485 W | ≈20.4% | −0.373 | 45.1 | 13.73 | product 2024, 2025 | — |
| SEG Solar SEG-495-BTD-BG | 495 W | ≈25.3% | −0.290 | 39.9 | 15.82 | product 2023, 2024, 2025, 2026 | 8 |
| Qcells Q.PEAK DUO XL-G10.d 485 | 485 W | ≥20.9% | −0.340 | 53.64 | 11.29 | product 2023 | 6 |
| AXITEC AC-450MH/144V | 450 W | ≈21.2% | −0.380 | 50 | 11.47 | — | 1 |
Calculated from the panel area (2.37 m²): about 20.4% for the 485 W class. 485 W over 2.37 m² equals about 204 W per square meter.
PVWatts v8 with typical-year weather gives about 813 kWh per year per 485 W panel in Los Angeles and about 890 kWh in Palmdale (20° roof, facing south, 14% system losses).
With γ = −0.373 %/°C, at a 77 °C cell temperature (hottest modeled hour in Palmdale) output is about 19.3% below the STC rating.
With the Tesla 1538000-xx-y (max DC 600 V, MPPT from 60 V, datasheet) in Los Angeles the calculator gives 2–12 panels per string (Voc at 2 °C = 47.7 V, Vmp at 74 °C cell = 30.3 V). Final design must follow the inverter manual and NEC 690.7.
Voltage check against the APsystems (Alt Power System) datasheet: Voc when cold 47.7 V vs max input 60 V; Vmp when hot 30.3 V vs MPPT low 28 V; recommended module power 265–570 W. Confirm on the microinverter maker’s compatibility list.
Yes. Rear gain depends on mounting height and ground reflectance.
HT66-18X-xxx was a PVEL Top Performer in 2024, 2025 (DH, HSS, LID+LETID, MSS, PID).