Losing Water Water Shortages Are a Major Problem for Future Energy Projects May 14, 2013 | Ethan Goffman | water, renewable energy, energy, water footprint watering crops Agriculture is just one of many competitors for limited water supplies. cleanwaterfund.org It’s easy to get obsessed with climate change as the predominant environmental issue and to neglect the complex interactions of deforestation, biodiversity loss, human population growth, ozone depletion and numerous other factors. One key factor is water, upon which we all depend not just for drinking, but for agriculture, cleaning, energy generation and ecosystem sustenance. The Thirsty Triangle: The Water Footprint of Energy Trade Between China, Canada, and the United States, a recent forum at the Woodrow Wilson Institute, reminded participants of H2O’s omnipresent role, suggesting that the water footprint could become as important as the carbon footprint for future energy projects. Michael Hightower of Sandia National Laboratories called greenhouse gas emissions “a very narrow indicator,” and suggested water will be part of a complex of factors for future decision making, that “we need to look at systems.” Using water footprinting as a major guidepost dramatically changes our energy future. Energy currently accounts for 8% of freshwater withdrawals. As aquifers are drawn down around the planet, conflict is growing around competing uses, and one of the uses is energy. Indeed, “water is becoming the Achilles heel of energy development,” said Hightower. He also emphasized how water availability will be affected by climate change, which is leading to a 10-20% reduction in precipitation. Furthermore, he worried about the cumulative impact of “droughts, floods, frequent storms and snowcover shrinkage.” In the United States, he explained, we maxed out our surface-water potential around 1980 and have moved to groundwater, yet water tables are shrinking. How Energy Systems Use Water—Lots of Water Energy development, then, will be dependent on water availability, which is regional and local. The current explosion of activity in the United States involving hydraulic fracturing (or fracking) will become much less tenable, as each drill site requires three to five million gallons of water. Since all water use is local, extraction will depend heavily on where a particular fracking site is located, how much water is available, and what other uses are competing for that water. Because shale reserves are greatest in areas facing water scarcity, Hightower pointed out, fracking’s future may be dim. Still, the use of brackish water rather than fresh could, to an extent, counteract that limitation. Nuclear plants, too, use a tremendous amount of water per kilowatt hour, about twice as much as coal (depending on plant size and other factors), putting their future at risk. Biofuel use may be even more limited, as this crop-based energy source, like all agriculture, has an enormous water footprint. Another surprising result of the water dependency of contemporary forms of energy generation is the large amount needed for concentrated solar plants, planned for use in the southwestern part of the U.S., as these are water cooled in an extremely dry region. (Not mentioned at the forum is the possibility of technological changes, such as the use of an alternative agent to water for fracking, biofuels grown in otherwise unusable water, or air-cooled concentrated solar). Examining the water footprint, then, substantiates the need for more investment in most forms of renewables, particularly wind, but also solar photovoltaic. Steve Renzetti, Professor of Economics at Brock University, discussed the water situation in Canada, which uses a vast amount of hydroelectricity. He pointed out some good news, namely that water use is getting more efficient; water intensity has declined steadily since 1990. For example, water use per unit of agricultural output has fallen due to technological improvements. The same is true for oil and gas extraction. Nevertheless, Canada’s overall water demand is projected to increase. From 2005 to 2030, a 100% increase in water use for energy is expected, with a 50% increase for agriculture. However, because energy generation and agriculture are currently only 1% and 10% of water use respectively, the overall increase is relatively small. To further increase efficiency, Renzetti suggested a modest fee for water use, since water withdrawal today is largely free. Another huge problem is pollution, often due to agricultural runoff; Renzetti called nonpoint source pollution “a devil to regulate.” Lake Winnepeg, notably, has been so choked with algal blooms that Renzetti described it as “probably North America’s biggest untold environmental disaster.” Significant water degradation also comes from air pollution rained downed upon waterways, for instance from heavy metals, much of it from coal. Renzetti stressed the need for better baseline data and more regulation of nonpoint sources. While the first two presentations covered North America, Qingwei Sun of Greenpeace China, discussed the water footprint as it pertains to the coal that powers China’s manufacturing boom. Indeed, the country is responsible for about half of global coal use, a key factor in the continuing rise in global greenhouse gas emissions despite the lingering recession. The majority of China’s coal reserves are in the northwest, the most arid part of the country, which contains 83% of China’s coal reserves but only 25% of its water. Indeed, major coal producing provinces such as Inner Mongolia and Shanxi have used up their government-allocated water quotas and may experience insufficient water in five years. The forum slighted trade issues, important for the “virtual water” included in any import or export product. That is, each export of, say, potatoes, represents the amount of water needed to produce that commodity. Areas with excess water can thus “virtually” sell that water to areas with a deficit. Instead, the forum mainly discussed water use in a vacuum, as if each individual country had only its own water to depend on. Selling Coal—And Coal’s Water Footprint An exception is the selling of coal to China. This also means selling the water footprint of that coal. One would expect a growing amount of coal from North America, and coal imports into China are indeed surging, although currently the vast majority comes from other countries, specifically Indonesia. Nevertheless, American coal companies, which have been losing business to natural gas, are gearing up to replace it with exports to China. This could make opposing such exports the next big environmental issue in the United States. Yet Sun personally believes major shipment of North American coal to China will not happen, since Beijing is financing the construction of new north-south transport facilities, along with water pipelines, to keep its own coal flowing internally. This certainly makes sense in view of the export-oriented policy of China, which seems loathe to become dependent on other countries. Still, the question remains whether the variety of demands for water will make it harder for China to continue exploiting its own coal at such an enormous rate. Perhaps it will be forced to turn to North America? On the other hand, China’s severe pollution, and the protests it is spurring, may push it to convert to renewable energy at an even faster rate than is currently the case, or even to slow its rate of growth and lead the country to seek a new definition of development. It is at least conceivable that China will become a proponent of development based on quality-of-life and long-term sustainability. The water footprint, then, seems likely to channel future energy decisions, although local management and new technology can offset some of these limitations. Yet, to me at least, the issue of scale seems likely to force wiser management of water resources than of carbon emissions. Not only does suffering from excessive water use occur much sooner, but the same locations that make unwise decisions will suffer most from those decisions. Although we can expect some water shortage disasters at local, and even national levels, overall, circumstances are likely to compel relatively wise management of water. Climate change, by contrast, is a true tragedy of the commons, causing harm at a distance in both time and space. Of course, we will have to monitor and manage our water supplies with increasing care, but climate change still seems to me the more dangerous long-term problem, a seductive thief stealing our future. - See more at: emagazine/blog/losing-water/#sthash.Hk0jDIr2.dpuf
Posted on: Tue, 30 Jul 2013 13:15:28 +0000
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