Recent advances in solar photovoltaic activities in Japan an new energy strategy toward 21 century

摘要

The current state of the art in recent progress of Japanese photovoltaic (PV) activities is overviewed. Firstly, a brief discussion is given on "the 3E Trilemma" which is the most important issue for the 21st century's civilization life. Secondly, a new strategy for the renewable energy promotion so called -Fundamental Principle to promote New Energy Developments and Utilization-, and its action planning for PV technology up to year of 2010 are introduced. Some new strategies with tangible actions such as tax reduction, government financial support of 1/2 subsidy of PV system developments for public facilities namely as "PV Field Test Experiments", and a 1/3 subsidy for the private solar house as "PV Solar House Plan" are demonstrated. Thirdly, recent R&D efforts in the field of solar cell efficiency improvement technology are reviewed together with progress of some new technologies such as multi-bandgap stacked solar cells, utilization of new materials; microcrystalline silicon (μc-Si), CIGS etc. In the final part of paper, a prospect of future industrializations of the photovoltaics is discussed, then possible new roles to contribute to the global environmental issues by the PV system developments are introduced with some live technologies in progress, such as ashing of pollutant gas, cleaning of water and "greening" the desert, etc.