pvlib.pvsystem.pvwatts_ac

pvlib.pvsystem.pvwatts_ac(pdc, pdc0, eta_inv_nom=0.96, eta_inv_ref=0.9637)

Implements NREL’s PVWatts inverter model 1.

\[\eta = \frac{\eta_{nom}}{\eta_{ref}} (-0.0162\zeta - \frac{0.0059}{\zeta} + 0.9858)\]

\[P_{ac} = \min(\eta P_{dc}, P_{ac0})\]

where \(\zeta=P_{dc}/P_{dc0}\) and \(P_{dc0}=P_{ac0}/\eta_{nom}\).

Parameters

• pdc (numeric) – DC power.

• pdc0 (numeric) – Nameplate DC rating.

• eta_inv_nom (numeric, default 0.96) – Nominal inverter efficiency.

• eta_inv_ref (numeric, default 0.9637) – Reference inverter efficiency. PVWatts defines it to be 0.9637 and is included here for flexibility.

Returns

pac (numeric) – AC power.

References

1

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