At present, most of Bord na Móna’s biomass is used for co-firing. Co-firing refers to the dilution of energy peat with biomass materials. This mix is then fired to produce heat, which in-turn produces electricity.
Sustainability is top of our agenda when considering biomass types and sources. We look at the full carbon lifecycle of the biomass we use. Great time and effort has been taken to measure carbon emissions at every step of the supply chain, including harvesting, processing, and transportation.
We have been co-firing with biomass at our Edenderry Power Plant since 2008, and have increased our use of biomass every year since then. In 2015, our biomass procurement and supply reached a record 320,000 tonnes. Already, this increased use of biomass has produced impressive results, with Bord na Móna’s carbon footprint reduced substantially over the past five to six years.
Sustainable forests have a number of by-products, including sawdust, bark from felled trees, and trees that are too small for milling. These by products are milled and mixed together to produce a type of sawdust. This is then compressed under tremendous pressure to produce pellets or briquettes. In this form, the biomass can be transported easily.
The term energy crops refers to vegetation which is grown to be later processed into electricity or fuel. This source of biomass is not as common as the previous examples set out above, but may become more popular in time. If Ireland’s demand for sustainable sources of biomass increases in the future, energy crops may have an important role to play. The most common forms of energy crops include woody vegetation like willow and grassy forms like miscanthus, also known as elephant grass.