Woodchips and pellets reduce GHG emissions by 65-100% – BTEC study finds
Solid biomass fuels – wood pellets and woodchips – result in a 65 to over 100 percent reduction in greenhouse gas (GHG) emissions in comparison to fossil heating oil, a new study released by Life Cycle Associates, LLC and the Biomass Thermal Energy Council (BTEC) finds. This exceeds the targeted 60 percent GHG reduction requirement for cellulosic biofuels replacing heating oil under the US Environmental Protection Agency’s (EPA) Renewable Fuel Standard (RFS) program.
The study “Life Cycle Analysis of Renewable Fuel Standard Implementation for Thermal Pathways for Wood Pellets and Chips”, prepared by Life Cycle Associates, under contract with Technology Transition Corporation, on behalf of the Biomass Thermal Energy Council (BTEC), 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 greenhouse gas emissions by displacing the use of conventional fossil fuels, like heating oil and natural gas. This new study quantifies the GHG advantages of wood fuels for the record and highlights the avoided emissions from the resource’s alternative fates, said Peter Thompson, BTEC Deputy Director.
Life Cycle Associates analyzes the energy and environmental impacts of fuels and energy systems and has completed numerous life cycle analysis studies, including those to establish fuel pathway carbon intensities (CI) for the California Low Carbon Fuel Standard (LCFS).
The benefits of avoiding agricultural burning or composting emissions are often overlooked in discussions about biomass energy, said Stefan Unnasch of Life Cycle Associates and Technical Manager of the analysis project team.
Since wood pellets and wood chips meet the GHG reduction targets under the RFS, are often made from waste biomass sourced from forest product mills, forest residue, fire hazard reduction, and culling of insect-infested standing dead trees, and have a significantly lower carbon intensity (CI) compared to heating oil and natural gas, the study recommends that EPA reevaluate the RFS and consider creating a pathway for thermal conversion of biomass to thermal energy.
Maintaining markets for wood processing residues supports the effort of keeping forests as forests across the country. The use of these manufacturing residues for renewable energy is such a market. Their use for energy displaces fossil fuels and avoids alternate fates which have substantially greater climate impacts, said Lew McCreery, Forest Products Technologist of the USDA Forest Service, Eastern Region State, and Private Forestry.
Currently, the EPA RFS2 does not include a fuel pathway for woody biomass as a heating fuel; however, this Rule includes numerous pathways that use biomass, including forest residues, as feedstock to produce liquid biofuels which replace fossil fuels.
If biomass-based thermal energy were included under the RFS2, it could generate a D3 Renewable Identification Number (RIN), valued in the study at US$1.50/RIN. For 1 MMBtu on an HHV-basis or 77 000 Btu on an LHV-basis, this would generate 12 RINs or US$312 per (short) ton of biomass (dry basis).
The use of fossil fuels for thermal energy (heating, cooling, industrial process) is an overlooked one-third of our energy country’s energy use. 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 scores. Opening the RFS up to some of the most efficient pathways to replace heating oil and other fossil fuels used for both heating and transportation would be a major win for rapidly and drastically reducing carbon emissions, said Dan Wilson, VP of Wilson Engineering Services and former BTEC Chair.