In Germany solar development owes much of its success to their so-called feed-in law. Here’s a web site that concisely describes how it works: http://www.solarbuzz.com/FastFactsGermany.htm
Here are the basics
- The "Feed-in Law" in Germany permits customers to receive preferential tariffs for solar generated electricity depending on the nature and size of the installation. Under the new tariff structure introduced in 2004, the base level of compensation for ground-mounted systems can be up to 45.7 euro cents/kWh. PV installations on buildings receive higher rates of up to 57.4 euro cents/kWh.
- The Feed-in Law fixes tariffs for approved renewable energy projects for a 20-year period from the plant commissioning and will apply incremental price cuts. Tariffs were initially set at 48.1 cents per kilowatt hour for solar energy, 8.6 cents per kWh for wind, from 9.6 to 8.2 cents per kWh for biomass, 8.4 to 6.7 cents per kWh for geothermal and 7.2 to 6.3 cents per kWh for hydropower, waste and sewage gas.
- Some German states have subsidy programs for PV installations that can be used in combination with the national Feed-in Law.
In other words, the German government subsidizes solar power in order to help it get a firm footing. They do the same, as it says above, for other renewables, but at a reduced rate.
In Japan , the competing cost of conventional electricity is so much higher that it goes a long way to make solar an economically sensible choice.