Wood pellets and chips result in a 65-100%+ reduction in greenhouse gas (GHG) emissions compared to heating oil, according to the Biomass Thermal Energy Council (BTEC).
The figures were highlighted in a study by the BTEC and Life Cycle Associates titled ‘Life Cycle Analysis of Renewable Fuel Standard Implementation for Thermal Pathways for Wood Pellets and Chips’.
The 65-100+ reduction in GHG emissions from wood pellets and chips exceeds the targeted 60% GHG reduction requirement for cellulosic biofuels, replacing heating oil under the Environmental Protection Agency’s (EPA) Renewable Fuel Standard (RFS) programme. The study was conducted under a grant issued by the US Department of Agriculture’s (USDA) Forest Service.
“It has long been known that using wood fuels for heat reduces GHG emissions by displacing the use of conventional fossil fuels, like heating oil and natural gas,” said Peter Thompson, BTEC’s deputy director.
“This new study quantifies the GHG advantages of wood fuels for the record and highlights the avoided emissions from the resource’s alternative fates.”
The use of fossil fuels for thermal energy (heating, cooling, industrial process) is an “overlooked one-third” of the US’s energy use, according to Dan Wilson, vice-president of Wilson Engineering Services and former BTEC chair.
“Low-value biomass residues are often treated as wastes with very poor carbon fates, require extremely little processing to become thermal energy, and are shown to have very low carbon intensity (CI) scores,” said Wilson.
“Opening the RFS up to some of the most efficient pathways to replace heating oil and other fossil fuels used for heating and transportation would be a major win for rapidly and drastically reducing carbon emissions.”
Lew McCreery, forest products technologist of the USDA Forest Service, Eastern Region State, and Private Forestry, commented: “Maintaining markets for wood processing residues supports the effort of keeping forests as forests across the country.
“Use of these manufacturing residues for renewable energy is such a market. Their use for energy displaces fossil fuels and avoids fates which have substantially greater climate impacts.”
Since wood pellets and wood chips meet the GHG reduction targets under the RFS, are often made from waste biomass sources from forest product mills, forest residue, fire hazard reduction, and culling of insect-infested dead trees, and have significantly lower CI compared to heating oil and natural gas, the study recommends that the EPA re-evaluates the RFS and considers creating a pathway for the thermal conversion of biomass into thermal energy.