Abstract We developed a model describing the photoluminescence spectra from hydrogenated microcrystalline silicon (μc-Si:H). From the model we derived analytical relations between the separation of the quasi-Fermi levels and PL-peak energy and intensity. These relations may be useful when photoluminescence or electroluminescence based methods are applied for characterization of μc-Si:H solar cells and modules. We compared the model with experimental PL spectra from a μc-Si:H solar cell. Our model can consistently explain the relation between the measured PL-peak intensity, energy and the measured open circuit voltage of the μc-Si:H solar cell.