Refuse Derived Fuel
What exactly is RDF? Is it a secondary product or a waste? And is it available on the open market as a cheap renewable fuel?
RDF is refuse-derived fuel and it is produced as an output from materials recycling facilities (MRFs). It is composed of treated residual waste that is not suitable for recycling.
Although the residual waste has been through a treatment process, the manufacture of RDF does not qualify as recovery and the RDF is still classified as waste. Unlike secondary fuels based on waste solvents, it does not have such a high calorific value as fossil fuels and cannot be used as a direct replacement for them. Instead, it is burned in energy from waste (EfW) plants. RDF is regulated in the same way as any other waste and can only be burned in an installation that complies with the requirements for waste incinerators, taken from the EU Industrial Emissions Directive.
Energy from waste can be classified as either disposal by incineration or recovery (code R1), based on whether its primary purpose is to produce energy or dispose of waste. The Waste Framework Directive distinguishes between disposal and recovery using a formula based on the efficiency of the plant. Defra explains this as follows.
The R1 formula calculates the energy efficiency of the municipal solid waste incinerator and expresses it as a factor. This is based on the total energy produced by the plant as a proportion of the energy of the fuel (both traditional fuels and waste) that is incinerated in the plant. It can only be considered recovery if the value of this factor is above a certain threshold. It is important to note that the calculated value arrived at via the R1 formula is not the same as power plant efficiency, which is typically expressed as a percentage.
