In the UK the Renewable Obligation Orders provides the mechanism for subsidies for electrity made form renewable sources.
Larger generators over 5MW generally obtain a subsidy through Renewable Obligations Certificates or ROCs which are traded with electricity suppliers.
Feed in Tariffs or FITs were introduced in 2010 and provide owners of smaller new British renewable installations (less than 5MW) guaranteed tariffs for their electricity. This power can come from wind, hydro, solar photovoltaic (PV), or gas created by anaerobic digestion of biomass (AD) (other than landfill or sewage). The tariff you will get (pence/kWhr) depends on the size and type of your generator. Wind projects for example in the 500kW to 1.5MW band will provide a 2010/11 FIT of 9.4p/kWhr. In addition there is an export tariff for the actual electricity you sell.
Most new projects under 50kW are required to be installed and accredited by the Micro-generation Certification Scheme (MCS) to get a feed-in-tariff. This is normally single house and small commercial projects.