The production of biogas is performed by the producer, using either the anaerobic digestion or gasification processes. The biogas is then upgraded to a higher quality of biomethane for gas injection.
Propane may be required to be added by the producer to raise the energy content of the gas.
The biomethane must then be sold to a shipper before it is injected into the grid. Ofgem can provide a list of licensed shippers.
Once the biogas has been upgraded to biomethane it will be transferred to National Grid’s network entry facility. From here the gas will be metered and the quality monitored. Odorant will also be injected to give the characteristic ‘gas’ smell.
Once these stages have been completed the gas can be injected into the distribution network for transportation.