The Energy Saving Opportunity Scheme (ESOS) was introduced by the Government in response to a European Union directive on energy reporting. The aim of the scheme is to reduce the UK’s carbon emissions by making it compulsory for large businesses to identify energy saving measures.

The Feed-in Tariff (FiT) is a government subsidy paid for renewable electricity generation and is a fixed payment per kilowatt-hour (kWh) of electricity generated. The rate paid varies by technology and also by size of project, with small to medium scale installations receiving higher rates.

The technologies eligible for FiTs are wind, solar photovoltaics (PV), hydro, anaerobic digestion and domestic scale micro-CHP.

The tariff levels reduce by gradual amounts each year (in line with expected technology cost reductions). This is called 'degression'.