Forest Biomass Supply Chains in Ireland: A Life Cycle Assessment of GHG Emissions and Primary Energy Balances

The demand
for wood for energy production in Ireland is predicted to double from 1.5
million m3 over bark (OB) in 2011 to 3 million m3 OB by
2020. There is a large potential for additional biomass recovery for energetic
purposes from both thinning forest stands and by harvesting of tops and
branches, and stumps. This study builds on research within the wood-for-energy
concept in Ireland by analysing the energy requirements and greenhouse gas
emissions associated with thinning, residue bundling and stump removal for
energy purposes. To date there have been no studies on harvesting of residues
and stumps in terms of energy balances and greenhouse gas emissions across the
life cycle in Ireland. The results of the analysis on wood energy supply chains
highlights transport as the most energy and greenhouse gas emissions intensive
step in the life cycle. This finding illustrates importance of localised
production and use of forest biomass. Production of wood chip, and shredded
bundles and stumps, compares favourably with both other sources of biomass in
Ireland and fossil fuels.