Biomass
State law already includes “trees or other vegetation” in its definition of “renewable energy”. The Legislative Task Force was directed to include “herbaceous crops, trees, agricultural waste, and aquatic plant matter” in its studies.
But when the Legislature passed the a law mandating that utilities build biomass energy sources, it specified “farm-grown closed-loop biomass”: including “poplar, aspen, willow, switch grass, sorghum, alfalfa, and cultivated prairie grass.” It also added a loophole for a northern MN mill burning “biomass residue wood, sawdust, bark, chipped wood, or brush;” and other projects using “waste wood, including chipped wood, bark, brush, residue wood, and sawdust.”
Sierra Club position
- Sierra Club does
not support using whole trees or logging waste (branches, forest floor
material) directly from forests in biomass plants, except those from
privately owned tree farms that did not recently replace natural
forests. This material is needed to replenish soil nutrients, in
ways that do not increase fire risk. Biomass operations often scrape
every stick and blade of grass from the soil, causing erosion and
leaching soils.
We do not oppose using marginal agricultural land for farms of hybrid trees. This type of farming uses less chemicals than corn or soybean agriculture and creates less stream turbidity. The Sierra Club is opposed to use of transgenic trees in plantations or natural forests because of the risks to native trees and ecosystems. - Sierra Club does support use of wood waste from mills. Any “biomass residue wood, sawdust, bark, chipped wood, or brush;” (216B.2424 subd. 5(e)(2)) or “waste wood, including chipped wood, bark, brush, residue wood, and sawdust” (216B.2424 subd. 6(f)) used in biomass plants should be mill waste, not harvested or salvaged from logging operations.
- Where applicable, Sierra Club does not support use of recyclable waste paper in biomass plants or municipal incinerators.
- The Sierra Club notes that crop residues have a role in maintaining soil fertility and structure and their removal for use as a fuel is not without significant impacts. Depriving soil of these nutrients may necessitate greater use of pesticides and chemical fertilizers, potentially canceling any environmental or economic benefit of using agricultural wastes as biomass. The use of pesticides and drainage technologies to grow crops have created significant environmental impacts and fuel use of crop residues would provide market incentives to increase these impacts. Crops grown specifically for fuel would have to be evaluated for their pesticide and soil productivity impacts on a case by case basis.
Contact
Lois Norrgard, Forestry Organizer,