The price of a residential photovoltaic generation system has been decreasing in Japan because of the inflow of low-priced products from Europe and China. The industry sources are much concerned about the decreasing profit of domestic makers. They say that the average price of a system dropped to 529,000 yen per kW lately, an 8.5% decrease from the previous year. Because a solar battery module accounts for 50% of a photovoltaic generation system in cost, countries capable of building solar modules cheap naturally have a strong competitive edge. However, you need to think about the background of the inflow of foreign products. European countries including Germany reduced the support for the introduction of a photovoltaic generation system. Actually, the world market is estimated to decrease 20% in 2011 from 2010. Then, Japan is a rather promising market because it will enact the system to buy whole amount of renewable energy next year. In a word, the policy to enhance the happiness of Japanese people ends up with the decreasing profit of Japanese makers and makes the domestic economy even worse. What an irony this is.