Learn from failure.
Japan had been leading solar cell market both in production and implementation till 2004. Sharp had been No.1 producer for a long time. But in 2007, it gave up No.1 position to Q Cells, a German company.
Everyone would know that Germany is heavily invested in renewables. They introduced feed-in-tariff which boosted German solar power market. And it's not only Germany - a lot other countries are pursuing renewable energy as policy goal.
A lot of countries, except for one country that once boasted World's No.1 solar cell technology and market - Japan.
There is no sign that Japan will start investing seriously in renewable energy as policy, at least as earnestly as other countries. Consequently, it is losing its ground on such a promising field and its leadership role in the market. How sad.
This shows that technology won't spur on its own; policy direction and support (including incentives and regulatory changes) really matters for this kind of paradigm shift.