Erratum to “Maximum Efficiencies of Indoor Photovoltaic Devices”

In the above paper (ibid., vol 3, no. 1, pp. 59-64, Jan. 2013), there is an error in the scale of Fig. 1. The corrected figure should appear as presented here. The correct maximum efficiency following the detailed balance model is close to 30% for a halogen lamp and for an incandescent bulb, respectively, and a bandgap close to the one of Germanium. The fluorescent tube reaches 50%, and the white RGB LED and the Phosphor LED achieve 64% and 57%, respectively. The maximum photovoltaic efficiency is 72% when irradiated by a sodium discharge lamp.