03/12/2009 02:19 pm ET | Updated May 25, 2011

What is Sustainability? Sustainability Primer Part 2

"We have the capacity and ability to create a remarkably different economy, one that can restore ecosystems and protect the environment while bringing forth innovation, prosperity, meaningful work, and true security. The restorative economy unites ecology and commerce into one sustainable act of production and distribution that mimics and enhances natural processes."
--Paul Hawken, The Ecology of Commerce

[Author's Note: This is the second part in a series based upon excerpts from Edition II of When Technology Fails: A Manual for Self-Reliance, Sustainability and Surviving the Long Emergency] 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.)

From looking at Daly's definition of sustainability, we see that few things in our modern world are actually built, processed, or manufactured sustainably, including what is generally referred to as "sustainable building", and that we have a long ways to go towards actually making our modern word sustainable. Building a sustainable world is not easy, but it is doable! More on this subject in the next part of my Sustainability Primer.

Green tip for the day: Fix it instead of throwing it "away." When an item is manufactured, far greater inputs in the form of energy and raw materials go into making most items than meets the eye, and far more waste is generated in manufacturing and refining these raw materials than the item that sits in front of you. For example, according to a UN University study, 1.8 tons of raw materials are used to manufacture the average PC, and most of these materials are dumped somewhere as waste. So, when you repair an item rather than throwing it "away," you are reducing your consumption and ecological footprint on the planet. It often seems hardly worth your time to sew a split seam on an item of clothing, upgrade a computer, or repair an appliance, but fixing something yourself, or spending a few bucks for someone else to fix it, is one more way of Doing the Right Thing. The exception to this rule is when the item is an old energy hog, such as a refrigerator that is more than ten years old, or a gas guzzling car. In these cases, the energy wasted by the old appliance or car over its lifetime is far more energy than what goes into making a newer and much more efficient replacement.

Matthew Stein is the author of When Technology Fails: A Manual for Self-Reliance, Sustainability, and Surviving the Long Emergency from Chelsea Green. For more information, visit and