The Oil and the Glory
The Texas solution: save water and reduce CO2 emissions
Paul Faeth is a senior fellow at CNA, a Washington, D.C.-based research and analysis organization. With climate-change officials from around the world gathered in South Africa for another frustrating round of post-Kyoto talks, we have some interesting news out of Texas: When you conserve water, you can mitigate climate change. Facing its worst single-year drought ...
Paul Faeth is a senior fellow at CNA, a Washington, D.C.-based research and analysis organization.
With climate-change officials from around the world gathered in South Africa for another frustrating round of post-Kyoto talks, we have some interesting news out of Texas: When you conserve water, you can mitigate climate change.
Facing its worst single-year drought ever, Texas is demonstrating synergies that accompany the extensive use of wind power, which requires no water and tamps down the need for water-guzzling coal-powered electric plants. The southwestern U.S. state has the largest installed capacity of wind power in the country — in October, wind production was a record 15 percent of the load, according to the Electric Reliability Council of Texas, the electric-grid operator known for short as ERCOT. That translates to a similar reduction in potential water demand. One finds similar results elsewhere where severe drought has struck, such as China.
The greatest use of freshwater in the U.S. is to cool electric power plants, comprising 41 percent of the total. Most is withdrawn from lakes and rivers. Of today’s two main power production options — coal and gas — gas uses less than half the water, emits almost no air pollution, and releases less than half the carbon dioxide of coal. Wind power, which is expanding quickly across the U.S., uses no water and produces no emissions. By reducing demand, energy efficiency also cuts water use and CO2 emissions.
This calculus will continue to be relevant since winter forecasts call for Texas’ drought to continue into 2012. There are two issues: There is simply not enough water to withdraw for cooling power plants; nor is there sufficient water in rivers and lakes to dilute the hot water coming from them. A similar, 2008 drought in the southeast U.S. brought 24 generators within weeks of shutting down. And last year, high ambient water temperatures forced the Brown’s Ferry plant in Alabama off line for most of the summer. Three months ago, ERCOT warned the state of potential blackouts because of high temperatures and a lack of cooling water.
Texas’ energy and water problems are also driven by population growth. The state had the fifth-highest growth rate in the U.S. from 2000-2010, at 20.6 percent, adding 4.3 million people, according to the 2010 Census. This led to a greater demand for water and power, and a conflict between water users and power providers. Opposition by local farmers and ranchers over water use, for instance, has forced a new coal-fired plant in southeast Texas to change its plans. Conventional cooling would use 8 trillion gallons of water a year; the newly configured plant will use a more costly alternative to cut use to 978 million gallons. Texas already has more coal-fired power plants than any other state, and withdraws more water to cool them. More coal-fired plants are planned, though recent experience has shown that the calculus can change.
As an alternative to coal, Texas could harness the energy-water-climate synergy. The state already has a substantial start by encouraging wind power, and there is potential for more. Another step would be to encourage more energy efficiency, which not only produces "negawatts" as Amory Lovins calls them, but also "negagallons" since reduced energy demand also eliminates the need for water.
The state would also benefit by meeting demand with natural gas rather than coal. Because of its higher efficiency, gas needs much less water for cooling. And, according to the Energy Information Administration, the average cost for new coal is $95 a megawatt-hour, which is still superior to wind’s $97 average cost, but much higher than gas, at $66 a megawatt-hour. Energy efficiency is about $25.
As suggested above, energy and water problems are not confined to Texas. China seems to have the most pressing situation because of persistent drought in the southeast but also because of its rapid economic growth. China’s energy and water use is swiftly expanding, and conflicts between the two are becoming more frequent. Ahead of the Durban climate-change talks, Beijing released an updated version of a white paper outlining how it plansto reduce the greenhouse gas intensity of its economy.
Among its plans, China is moving to dry cooling for coal plants and major increases in hydropower, and has also become the world’s largest manufacturer and consumer of renewable technologies. Its 12th Five-Year Plan includes a 130GW target for total installed wind capacity, more than two-and-a-half times the expected U.S. amount. China’s wind capacity will then roughly equal the plan’s target for added hydro-electric capacity. While China is moving to slow the increasing rate of water consumption and CO2 emissions, it does not appear that the government has made the connection between the two.
Other dry regions of the globe are certain to face these same challenges in the decades ahead. Among them may be drought-stricken east Africa. Broader use of energy supply options that meet demand while simultaneously reducing water use and greenhouse gas emissions will become an essential strategy.
Paul Faeth can be reached at firstname.lastname@example.org