If trees are replanted after harvesting, woody biomass is proven to give lower carbon emissions than coal and it makes sense to phase in a few more plants. Wood currently is not as efficient as coal and co-firing is still being explored with 15% co-firing showing promise. Waste wood biomass groups talk about branches, bent trees that can’t be used for lumber, bark, and shavings as their fuel source. This wood would otherwise rot in the forest or in a woodpile and produce the same amount of carbon as burning it for energy.
Semi-truck transportation of wood to the plant location is energy intense which is why biomass plants source the majority of the fuel within a 60-mile radius, others propose up to 200 miles Better engine efficiency would go a long way in making woody biomass transportation more feasible and efficient.Another source of carbon is the soil the trees are harvested from. Soil holds more carbon than trees because the soil has been there longer. Every tree before the current one has decayed leaving its carbon to be absorbed by the soil. New York Forestry Service did a study comparing carbon emitted from soil versus carbon absorption by newly planted trees and found the soil emits carbon faster than trees can absorb it. This means there won’t be adequate carbon sequestration if the soil is disturbed emitting more carbon than the new trees can sequester. On top of that, the newly harvested trees would be burned for fuel releasing even more carbon. Making a net increase in atmospheric carbon.
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