  We derive exact analytical solution of the Shockley-Queisser (SQ) model and
present all photovoltaic (PV) characteristics in compact and convenient form
via the Lambert W function. We show that the SQ condition of chemical of
equilibrium between photocarriers and emitted phonons leads to a new
thermodynamic relation between the maximal conversion efficiency and the
photo-induced chemical potential. Also, we consider kinetics of PV conversion
and establish relation between the photocarrier collection time and
photocarrier lifetime. We consider photonic and electronic requirements for
approaching of SQ limit in semiconductor PV devices and highlight a role of
photon reabsorption.
