Biomass is a renewable energy alternative to fossil fuels, burning wood and other organic matter in place of coal or oil. Most biomass heating systems burn wood pellets, chips or logs to generate heat, either directly or via a central heating or hot water system. In May 2019, the UK went an entire fortnight without using coal-fired generation, the first time in over 100 years. Biomass-fired former coal stations played a substantial role in this.
Biomass represents a significant reduction on carbon emissions compared to burning fuel oil or coal, but some emissions are still generated. As such, there is some controversy over the label clean energy when applied to biomass. Biomass is typically also limited by the amount of fuel available, with boilers requiring large storage hoppers and regular deliveries of new fuel to continue to operate. This can often prove impractical for many businesses.
Biomass was classed as carbon neutral when the UK, as a member of the EU at the time, laid out a commitment to achieving a 20% increase in renewable energy by 2020 back in 2009. Currently, around half of energy across the EU classed as renewable comes from biomass. The Drax power station in North Yorkshire, which has been converted from coal to biomass, provides around 5% of the UK’s total energy demand. Every two hours, the equivalent of an entire freight train of wood pellets is burnt by the plant.
Critics of biomass have stated that its carbon neutral credentials have been overstated, and even that it is a more carbon intensive fuel source than coal. This is largely due to the argument that it takes between 44 and 104 years for new trees to grow and remove the equivalent amount of carbon from the atmosphere that was generated by the biomass process.