There are many different types of renewable energy. Most, but not all, are eligible either for the FITs or for the Renewable Heat Incentive.
Renewables covers a very broad range of energy production technologies that are suitable for virtually any type of property – homes, offices, industrial units, schools, hospitals, and so on.
These can be grouped into three categories:
(so are covered by the Renewable Heat Incentive, not the Feed-in Tariffs)
Producing heat and electricity together is call Combined Heat and Power (CHP)
In fact anaerobic digestion (AD) produces biogas which can be used for electricity generation, heat production, combined heat and power or even be fed into the natural gas grid.
There are many factors to consider when choosing which renewable energies will suit your property and requirements.
The main factors for FITs-eligible renewable technologies are discussed here.