This grass blog has focused mainly on the practical aspects of stoves, boilers, and developing a market for grass combustion. The previous posts show a common acceptance of a certain beauty and simplicity integral to growing and using a fuel so appropriate to upstate rural New York, but we have not paid much attention to the underlying systems. For me, one of these dynamic subsystems is soil, a topic that takes high priority – not only because harvested biomass subtracts from the soil – but also because part of the rationale for biomass is carbon neutrality which is mediated between plant photosynthesis, soil, decay, and the atmosphere. Soil is important because, like fossil fuels, its replacement takes place over geological time. It takes 200 to 1000 years to rebuild topsoil naturally to a depth of barely one inch. And, like so many agricultural endeavors, combusting biomass is a low-profit transaction – low profit at both the point of raw material sales and of densified finished product. So – as has happened to agriculture in so many places – the temptation is always to produce on a larger scale in order to increase profit.
I am not a soil scientist and this brief summary of soil ecosystems comes from a more expanded discussion in a book called Nature’s Services edited by Gretchen Daily and published by Island Press in 1997. Some of the ecosystem services listed that soil supplies are
- Participation in the hydrological cycle where certain characteristics of soil (ie organic content) in combination with growing plants protect it from erosion and transpire water back into the atmosphere.
- Retention and delivery of nutrients to these plants. This also depends on soil organic matter, as well as species diversity both in plants and soil bacteria.
- Disposal of wastes and dead organic matter through decomposition, recycling and diverse microbial species closely related to 2) above
- Participation in the regulation of the biogeochemical cycles – particularly carbon and nitrogen, which are very interdependent, vary in different climates and seasons, and are not completely understood.
It is almost impossible to put a price on these services, but estimates are always in the billions of dollars. A new school of economics, Biophysical Economics, formed as a response to energy and environmental events of the 1970s, uses thermodynamics and the study of energy flows as additional explanation for economic systems. These economists recently had their annual meeting in, of all places, the State University of New York’s College of Environmental Science and Forestry in Syracuse (2009). Ecological Economics, another non-main-stream economic school of thought, which sees human economy as a subsystem of a complex global ecosystem, has developed from Biophysical Economics.
All this is important because standard classical economics, based only on the laws of human supply and demand, does not sufficiently explain the kind of thinking that must be the basis for biomass energy. The “profit” in biomass energy must recognize the synergistic effect on the community and the value of ecosystem services to be profitable. The real agricultural battle is not between food and fuels, but between food, fuels, and the health of the environment. Unless humans learn to do the equivalent of tithing back to the ecosystem we will overuse it. In my opinion, biomass, in order to really make sense, must be more than just a part of alternative energy but also a part of alternative economics, a revolution in what capitalism encompasses.