The nationwide output energies of photovoltaic (PV) modules were estimated using the meteorological data in the Japan Meteorological Agency (JMA) and the performance of PV modules. Global tilted irradiance (GTI) is needed to estimate the output energy of PV modules. However, the available measured data are typically restricted to global horizontal irradiance (GHI) in the JMA. In this study, GTI was estimated from GHI using the separation methods. The optimum installation angle estimated using the software released by New Energy and Industrial Technology Development Organization was used as a tilt angle at each location. The output energies of four PV modules (multicrystalline silicon, amorphous Si, a-Si/microcrystalline silicon tandem, and a-Si/a-SiGe/a-SiGe triple junction) were estimated. Nationwide output energies in Japan were estimated using the performance of each PV module and estimated GTI. The output energies were estimated considering module temperature and solar spectrum distribution. The results indicate that the method of using performance and meteorological data is useful for estimating the output energies of the PV modules around Japan. (C) 2013 Elsevier Ltd. All rights reserved.