— Paul Hawken, The Ecology of Commerce
Every day we hear about topics like sustainable growth and sustainable building, but what does it really mean to be “sustainable?” The economist Herman Daly has suggested three simple rules to help define sustainability:
- For a renewable resource –– soil, water, forest, fish –– the sustainable rate of use can be no greater than the rate of regeneration of its source. (Thus, for example, fish are harvested unsustainably when they are caught at a rate greater than the rate of growth of the remaining fish population.)
- For a nonrenewable resource –– fossil fuel, high-grade mineral ores, fossil groundwater –– the sustainable rate of use can be no greater than the rate at which a renewable resource, used sustainably, can be substituted for it. (For example, an oil deposit would be used sustainably if part of the profits from it were systematically invested in wind farms, photovoltaic arrays, and tree planting, so that when the oil is gone, an equivalent stream of renewable energy is still available.)
- For a pollutant, the sustainable rate of emission can be no greater than the rate at which the pollutant can be recycled, absorbed, or rendered harmless in the environment. (For example, sewage can be put into a stream or lake or underground aquifer sustainably no faster than bacteria and other organisms can absorb its nutrients without themselves overwhelming and destabilizing the aquatic ecosystem.)
- Concentrations of substances extracted from the Earth’s crust;
- Concentrations of substances produced by society; or
- Degradation by physical means.
- And in that society, people are not subject to conditions that systematically undermine their capacity to meet their needs.
- Stored deposits: In a sustainable society, nature is not subject to increasing concentrations of potentially toxic materials that have been “liberated” from where they were stored as deposits inside the Earth’s crust. Mankind has been refining natural substances, such as mercury, lead, and radioactive materials, in unnatural concentrations. These substances that were previously bound into stable, durable matrices, such as bedrock or coal, are now accumulating in the biosphere, where they are metabolized into living organisms at ever increasing concentrations. Nothing disappears from our world, and everything that is not bound into a solid, stable matrix eventually disperses into the ecosystem.
- Synthetic compounds and other unnatural material byproducts of society: In a sustainable society, nature is not subject to increasing concentrations of unnatural synthetic compounds. If this condition is not met, eventually the concentrations of these substances will reach concentration levels where irreversible changes begin to occur, with potentially dire consequences. The solution is to proactively substitute more common compounds, or ones that break down easily, for certain persistent and unnatural compounds, and for society to use substances efficiently. Remember that even using less of a toxic compound (improved efficiency) will still add up over time to too much of a bad thing, if this compound decomposes slower than the rate at which it is inserted into the biosphere.
- Physical degradation of ecosystems and natural resources: We must draw our resources from well-managed ecosystems. Our health and prosperity depend on the capacity of nature to restructure our wastes into new resources. Human activities need to work in harmony with the cyclic principles of nature.
- Human needs: Unless basic human socioeconomic needs are met worldwide through fair and efficient use of resources, it will be difficult to coordinate efforts and cooperation to meet conditions one, two, and three on a global scale. In a sustainable society, human needs are met worldwide.
Matthew Stein is the author of the highly praised book When Technology Fails (Chelsea Green 2008) a comprehensive manual on sustainable living skills. As the owner of Stein Design & Construction, he has built hurricane resistant, energy efficient and environmentally friendly homes. The mechanical engineering side of his firm specializes in product design and development. Among other things, Mat has designed consumer water filtration devices, photovoltaic roofing panels, medical bacteriological filters, emergency chemical drench systems, computer disk drives, and portable fiberglass buildings. In recognition of his expertise, Stein has appeared on numerous radio and television programs and is a repeat guest on Fox News, Lionel, Coast-to-Coast AM, and the Thom Hartmann Show. He has also written several articles on the subject of sustainable living and is a guest columnist for the Huffington Post. Stein is a graduate of the Massachusetts Institute of Technology (MIT) where he majored in Mechanical Engineering. He is an active mountain climber and serves as a guide trainer for blind skiers with the Ski for Light cross-country program. Stein currently resides with his wife Josie in the High Sierra Mountains near Lake Tahoe, California.