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The Environment Canada Policy Research Seminar SeriesWhat Would a Sustainable World Look Like? Dematerialization vs. Detoxification
Environmental sustainability is notoriously difficult to define. For our purposes, it should be defined in terms of the quantity and toxicity of material and energy throughputs, combined with an appraisal of human preferences. Sustainability has been measured via the Ecological Footprint. If, for a given area, human energy and materials use and waste release exceeds the former natural system's energy use and waste assimilative capacity, then we have overshot the area's Ecological Footprint, and the situation is not sustainable. Calculations of our Ecological Footprint have developed countries using resources and producing waste at a rate several times that at which their physical areas would warrant. Dematerialization, reducing flows of energy and material for a given level of well-being, is where most of our efforts on the environmental front have been concentrated over the last few decades. Much of this dematerialization can be accomplished through energy and materials efficiency gains, while lifestyle changes in consuming habits are much more difficult to effect. Detoxification focuses on the kind, rather than the amount, of flows on the assumption that the quantity of energy and material flows do not matter as long as they are environmentally benign. This can be accomplished through biomimicry - by matching human energy and material flows with natural flows. It may also be possible to surpass natural bioproduction and natural bioassimilative capacity. The Turpan Depression, an area of the Western Chinese province of Xinjiang, is desertic and about 150 metres below sea level, yet supported several ancient cities with populations of 10 to 20 thousand. How did these barren areas support such cities? The secret lies in the underground tunnels, or Karez, that run for forty kilometres from the Bogda mountains into the Turpan Depression, bringing the water that sustained the rich agricultural production of cities such as Jioahe. These cities dramatically overshot the natural bioproduction of their environment. According to Ecological Footprint analysis, these cities were unsustainable. They lasted, however, for more than two thousand years. Human enhancement to natural bioproduction can be accomplished by adding water, improving soil fertility, genetic engineering, using fossil fuels (stored bioproduction) or by using solar energy directly through wind power, small hydropower or photovoltaics. These kinds of human enhancements of the natural assimilative capacity are sustainable, but only as long as the "beyond nature" use of energy and materials is not toxic. One of the most important emerging opportunities for detoxification is the decarbonation of fossil fuels. Rather than a dream of the distant future, fossil fuel decarbonation is something that is happening today, albeit on a small scale. In the North Sea Sleipner gas field, the carbon dioxide content of natural gas must be reduced from 9% to 2.5% before it can be sent to market. Instead of venting it to the atmosphere as is done traditionally, the separated CO2 is being injected into a saline aquifer located below the ocean floor. Although more research is required, geologists believe that the CO2 will be stable and without negative effects. Decarbonation of fossil fuels with concomitant sequestration of CO2 is already technically possible. Oxygen blown gasification of fossil fuels followed by a water gas shift will produce pure hydrogen gas, which burns cleanly to produce inert water, and pure CO2 , which can then buried in deep aquifers, old oil and gas reservoirs, or perhaps used to displace methane from coal beds. Estimates of global capacity for sequestering this CO2 range from 500 to 1000 years, which coincides nicely with estimates of global fossil fuel supplies. Decarbonation of fossil fuels will likely be less expensive than using renewable sources of energy, without the perceived risks associated with nuclear power. The hydrogen gas produced could be used to generate electricity by combustion or with hydrogen fuel cells, resulting in zero toxicity at the end-use stage. Assessing the possibility of a non-toxic fossil fuel strategy for the future involves asking the question, what will/should humans want. The markets and wants of people living in developed countries must be assessed in concert with the overwhelming needs of five billion people in the developing world. A sustainable future may entail a combination of dematerialization and detoxification, but the pressing needs of developing nations have led to some policy shift towards detoxification. In the context of the environmental sustainability debate, the Ecological Footprint constraint is morally attractive, but not thermodynamically or physically accurate. We may not be as constrained by natural bioproductive and assimilative capacity as we would like to think we are. Strong forces are pushing us towards the detoxification strategy, but should we want that? Both the dangers and the benefits need to be carefully considered. BiographyMark Jaccard is associate professor and Director of the Energy and Materials Research Group in the School of Resource and Environmental Management at Simon Fraser University. He received his PhD at the Institute of Energy Economics and Policy at the University of Grenoble in 1987. Dr. Jaccard has been Professor in the School of Resource and Environmental Management since 1986. He served as Chair and CEO of the B.C. Utilities Commission from 1992-1997, while on leave of absence from university. He was a member of the Intergovernmental Panel on Climate Change from 1993-1996 for the production of the IPCC's Second Assessment Report. Since 1997 he has served as an international member of the China Council for International Cooperation on Environment and Development. He has advised governments, business and NGO's throughout the world and has chaired several task forces and inquiries in areas such as electricity market reform, gasoline pricing and greenhouse gas emission policies. List of articles and reports by Dr. Mark JaccardCompiled in support of an Environment Canada Policy Research Seminar, held in Hull on January 19, 2001.
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