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Building-integrated solar panelErgosun Holdings

Ergosun Holdings Ergosun 17.5W Black

20 cells, BIPV module. Power classes 15–18 W in the CEC list.

CEC listed · Jun 11, 2024UL 61730Building-integrated (BIPV)
Power class
  • Power (STC)18 WCEC nameplate
  • Efficiency≈12.6%calculated from area
  • %/°C Pmax−0.353CEC listing test
  • PTC / STC94.3%PTC 16 W (CEC)

Power classes

CEC PV Module List (Oct 7, 2026) · Cali-Graf calculation · 2 models
ModelPmaxVoc, VIsc, AVmp, VImp, AEfficiencyPTCCEC listed
Ergosun 15 W Black15 W12.001.6510.001.45≈15.0%14 WSep 11, 2026
Ergosun 17.5W Black18 W12.801.8510.001.45≈12.6%16 WJun 11, 2024
≈ efficiency = Pmax ÷ CEC-listed area 0.1 m².

Heat & cold behaviour

CEC PV Module List (Oct 7, 2026) · Cali-Graf calculation
CEC listing test
Pmax coefficient γ−0.353 %/°C
Voc coefficient β−0.347 %/°C
Isc coefficient α+0.052 %/°C
Operating cell temperatureNOCT 40 °C
Vmp coefficient ≈ γ − α (CEC); 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
15 W12 W9.2 V × 1.3 A——
18 W19.9 W8.9 V × 2.24 A——
Pmax = Vmp × Imp from the CEC listing; low-light efficiency = Pmax at 200 W/m² ÷ (20% of STC Pmax).

Inverter compatibility & string sizing

CEC PV Module List (Oct 7, 2026) · Cali-Graf calculation · NLR PVWatts v8
13.8 V
Voc when cold
per panel
8 V
Vmp when hot
per panel
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. β is the CEC-measured coefficient; NEC 690.7 calculations use the datasheet value.
Integrated roof products are wired per the manufacturer’s system design.
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 Angeles1,6762911,7326.08
Palmdale1,8353212,8456.69
Chula Vista1,6963011,8726.11
Huntington Beach1,6432911,5015.89
Riverside1,6963011,8726.21
Santa Clarita1,7243012,0686.28
766Jan766Feb984Mar1,086Apr1,073May1,140Jun1,201Jul1,215Aug1,063Sep937Oct806Nov697DeckWh per month · Los Angeles
PVWatts models a standard roof-mounted module; integrated roof products are not modeled separately.
Estimate for comparison, not a quote: shading, roof orientation and local losses change real output. Roof mount, 20° tilt, south, 14% system losses.

Questions & answers

How efficient is the Ergosun Holdings Ergosun 17.5W Black?

Calculated from the panel area (0.12 m²): about 12.6% for the 18 W class. 18 W over 0.12 m² equals about 146 W per square meter.

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

PVWatts v8 with typical-year weather gives about 29 kWh per year per 18 W panel in Los Angeles and about 32 kWh in Palmdale (20° roof, facing south, 14% system losses).

How much power does it lose on a hot roof?

With γ = −0.353 %/°C, at a 77 °C cell temperature (hottest modeled hour in Palmdale) output is about 18.3% below the STC rating.

Sources

  1. California Energy Commission — Solar Equipment Lists, PV Module List (snapshot Oct 7, 2026).
  2. NLR (formerly NREL) — PVWatts v8, NSRDB PSM v3 typical-year weather for Los Angeles, Palmdale, Chula Vista, Huntington Beach, Riverside, Santa Clarita.
  3. Cali-Graf calculations — formulas and inputs are shown next to each calculated value (efficiency from area, temperature-corrected voltages, string sizing, energy estimates).