太陽光発電技術の開発・普及に対する支援政策の歴史

抄録

Developing new renewable energy sources, such as solar photovoltaics (PV), is a key to establishing climate-friendly economy. Japan has been one of the centers of research, development, and diffusion (RD&D) of PV since the 1970's. While it is true that Japan was outnumbered by Germany in installed capacity and by US and Chinese companies in production in recent years, Japan still retains an important position in the world PV market. This paper examines the history of public policies for RD&D of PV in Japan, focusing on two kinds of policies, namely, public support for R&D under the Sunshine Program and various market creation policies in the early 1990's. Based on literature survey and interviews with key persons involved, the paper reveals that those support policies played an indispensable role to accelerate RD&D of PV technology. The Sunshine Program provided stable R&D budgets and space for technology learning throughout the 1980's to 1990's, and contributed to the progress of solar cell efficiency and cost reduction. The various market creation policies in the early 1990's also created regulatory and economic conditions that were necessary to commercialize residential PV systems, and became the direct driver to launch the initial PV market.