Anaerobic digestion (“AD”) is the process of using organic materials including food, agricultural wastes, and crops.
These biodegradable wastes are broken down by naturally occurring micro-organisms in the absence of oxygen-producing methane-rich biogas. This biogas is used to produce heat and electricity or upgraded to methane and injected into the gas grid.
The AD process also produces a nutrient-rich substrate that is used as a substitute for chemical fertilisers. A summary of the AD process is shown below.
*CO2 emissions are approximately 90% lower than natural gas. The input organic material utilised in the conversion process absorbs CO2 from the atmosphere as part of the natural carbon cycle.
Biomass power technologies convert renewable biomass fuels into heat and electricity using processes similar to those employed with fossil fuels. At present, the best way of generating electricity from biomass is combustion direct-firing. The wood provided for the combustion direct-firing process is sourced responsibly to offset CO2 being produced from the burning.
Combustion systems for electricity and heat production are similar to most fossil-fuel fired-power plants. The biomass fuels burned in a boiler to produce high-pressure steam. This steam is introduced into a steam turbine, where it flows over turbine blades, causing the turbine to rotate. The turbine is, in turn, connected to an electric generator. The steam flows over and turns the turbine. The electric generator rotates, producing electricity. This is a widely available, commercial technology.