Generally speaking, you can differentiate between naturally growing markets and incentive driven markets. In the former, low-cost solar water heaters are already an economic alternative for households to produce hot water instead of using fossil fuels or electricity. Some examples are: China, which is the biggest solar thermal market in the world, Cyprus which has one of the highest solar thermal capacities in operation per capita in the world, and Turkey, which is the third biggest market in the world.
In incentive driven markets like Germany, there are grants for households and companies. In Austria there is a nationwide subsidy scheme for hotels and guesthouses and there are grants at a provincial level for household customers.
A third category is markets driven by legal frameworks such as solar obligations. The most famous example is Israel, where the government – because of the oil crisis – passed an obligation applying to all new residential buildings as well as hotels, old people’s homes and boarding schools 29 years ago. Spain followed two years ago with a national solar obligation. In the meantime 15 countries more adapted renewable building laws or solar obligations. You find further news on this issues in the filter section "key pillars", then "policy" and "obligation".
Further information: “Best practise regulations for solar thermal”, Study by the European Solar Thermal Industry Federation (ESTIF), August 2007 http://www.estif.org/fileadmin/estif/content/policies