pvlib.pvsystem.pvwatts_dc(g_poa_effective, temp_cell, pdc0, gamma_pdc, temp_ref=25.0)[source]

Implements NREL’s PVWatts DC power model 1:

\[P_{dc} = \frac{G_{poa eff}}{1000} P_{dc0} ( 1 + \gamma_{pdc} (T_{cell} - T_{ref}))\]
  • g_poa_effective (numeric) – Irradiance transmitted to the PV cells in units of W/m**2. To be fully consistent with PVWatts, the user must have already applied angle of incidence losses, but not soiling, spectral, etc.

  • temp_cell (numeric) – Cell temperature in degrees C.

  • pdc0 (numeric) – Nameplate DC rating.

  • gamma_pdc (numeric) – The temperature coefficient in units of 1/C. Typically -0.002 to -0.005 per degree C.

  • temp_ref (numeric, default 25.0) – Cell reference temperature. PVWatts defines it to be 25 C and is included here for flexibility.


pdc (numeric) – DC power.



A. P. Dobos, “PVWatts Version 5 Manual” http://pvwatts.nrel.gov/downloads/pvwattsv5.pdf (2014).