Industry Profile
Clean coal gasification plants, like this one in Kentucky, could be built in Washington to provide much of the state’s future electricity needs.
Making headway in an environmentally conscious world by Danielle Rhéaume
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or many, coal brings to mind soot-covered faces, dangerous underground mines and a certain coal miner’s daughter. What coal should also bring to mind is its usefulness for generating electricity for many of the appliances and machines that we depend on each day—including the press that printed this magazine, the computer where you check your email each morning, or even the lights hanging over your head as you read this. Without a doubt, coal is difficult to live without. Fortunately, with recent advances in clean coal technology, we shouldn’t have to.
the Clean Air Mercury Rule to permanently cap and reduce mercury emissions from coal-fired power plants for the first time ever. Around the same time, the EPA issued the Clean Air Interstate Rule, a rule meant to dramatically reduce air pollution crossing state boundaries. Together, these rules created a strategy to reduce emissions throughout the United States. They also heralded the call for innovative, energy-efficient and environmentally responsible alternatives for using coal (the source of about half the electricity consumed by Americans) so that it is not eliminated from our menu of energy resources.
The best of fuels, the worst of fuels Coal “is the best of fuels” according to Kenneth Deffeyes, author of Beyond Oil, “because it’s the most plentiful and least expensive U.S. energy source.” Not only does coal account for more than 90 percent of recoverable fossil fuel reserves, it is also estimated that, at current rates of recovery and use, America’s coal reserves should last at least 200 years. Not just that, the energy content of our nation’s coal resources exceeds the sum total of the entire world’s known recoverable oil. This makes the U.S. a veritable Saudi Arabia of coal. However, Deffeyes also described coal as “the worst of fuels,” for a long list of reasons: killer smog, acid rain, atmospheric carbon dioxide, mercury pollution, acid mine drainage, and a choice between hazardous underground mines and surface-disturbing open-pit mines. In 2005, these problems prompted the Environmental Protection Agency to issue
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Burning coal the old-fashioned way Burning coal to generate electricity is a straightforward process. In most coal-fired power plants, chunks of coal are crushed into fine powder before being fed into combustion units and burned. Heat from the burning coal then generates steam that spins one or more turbines to generate electricity, and create—as an undesirable byproduct—the pollution Deffeyes wrote about. Coal has been, and will continue to be, burned like this for years to come, especially in countries with increasing energy demands and few emissions limits, like China or India. However, in the United States, where increased concern for the environment is shaping energy and emissions regulations, cleaner coal technology is making headway and getting attention.
Coal Gasification
The Clean Coal Process
Source: U.S. Department of Energy
Cleaner coal through technology One advance toward cleaner coal-fired energy has been Integrated Gasification Combined Cycle technology. Rather than burning coal directly, gasification breaks down coal — or virtually any carbon-based material — into its basic chemical constituents. In the first step of IGCC, coal is converted into a synthetic gas — or “syngas.” The steam from the gasifier is captured and used for power generation, as the syngas is scrubbed free of pollutants and particles. In the second step, the clean syngas is burned in a combustion turbine used to generate electricity. As this happens, waste heat from the combustion turbine is recovered and used to generate steam, which then feeds a steam turbine generator for additional electrical generation. This process requires less water and produces less waste and air pollution than burning coal the old fashioned way. According to the liberal Progressive Policy Institute, “today’s IGCC plants operate at about 40 percent efficiency compared with the roughly 33 percent efficiency of conventional plants, meaning they burn less coal to yield the same amount of energy and thus emit fewer pollutants. Experts say that future gasification plants should achieve efficiencies of 50 percent and higher.” Energy Northwest, a public agency made up of 19 public utilities in Washington, hoped to build an IGCC plant — the Pacific Mountain Energy Center (PMEC) — on an 80-acre industrial site in Kalama, just south of Longview. The PMEC plant, like most IGCC plants, would have increased efficiency and reduced
pollution from mercury and other pollutants, though it would not have greatly reduced emissions of CO2, which is said to contribute to climate change. Energy Northwest intended to offset emissions by purchasing carbon credits. Carbon credits give monetary value to the cost of polluting the air and create a market for reducing greenhouse emissions.
CCS technology “If coal is to have a future as a major fuel in the twentieth century and beyond, this is what it might look like: smokestacks effective-
ly turned upside down, shooting CO2 into subterranean rock formations rather than up into the sky,” wrote Craig Canine, in a feature article for OnEarth magazine — a publication of the liberal Natural Resources Defense Council. The benefit to IGCC plants is that separating and capturing CO2 from a syngas stream is far more straightforward and affordable than it is with conventional plants. Once CO2 is captured, it can be transported and stored underground in a process called Carbon Capture and Storage (CCS). When CO2 is
The ancient origins of coal Coal is a combustible sedimentary rock made mostly of carbon and hydrocarbons. Its energy comes from the energy stored by plants that died and were trapped under layers of water and dirt hundreds of millions of years ago. By the time it’s ready for mining, the heat and pressure from the top layers have turned the primitive plants into hard, black coal. If the coal is buried less than 200 feet underground, it can be gathered through surface mining. Surface mining is done with huge earth-moving machines and costs considerably less than underground mining. To remove coal from deep beneath the ground, miners ride an elevator down a shaft—sometimes up to 1,000 feet deep—where they use machinery, muscle and explosives to remove the coal. After being mined, the coal is cleaned, processed and transported to market via barge, ship, truck, pipeline or train. Whenever possible, coal-fired electric power plants are built near coal mines to lower transportation costs. In 2005, U.S. coal mines produced a record 1.1 billion short tons of coal. Most of it came from Wyoming, followed by West Virginia, Kentucky, Pennsylvania and Texas—the top coal-producing states.
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sent underground, it is believed to combine well with basalt and form calcium carbonate, which is solid like limestone. CO2 is also useful for recovering more oil from otherwise “tapped” oil fields. Because of this, enhanced oil recovery presents an affordable opportunity to sequester carbon, since recovered oil revenues help to offset the sequestration costs, while also reducing the need for oil production elsewhere. In late November, the Energy Facility Site Evaluation Council suspended the Kalama PMEC plan, stating that Energy Northwest’s application did not meet recent statutes of ESSB 6001, also known as the Climate Change bill. This bill codifies the governor’s clean-energy development and greenhouse-gas reduction goals. According to EFSEC, statutes within this bill require “new facilities generating more than 1,100 pounds of greenhouse gases per megawatt-hour of electricity to sequester greenhouse gases to this level or below.” Furthermore, any application pending on the date that the law became effective “must include a carbon sequestration plan.” EFSEC called the PMEC proposal a “plan to make a plan” and stated that “it does not identify steps it will take to implement sequestration ... It proposes that eventually, at some indefinite future time, it will seek to develop a specific plan for accomplishing the purposes of the statute.” EFSEC also stated that the plan is fundamentally flawed, because “it asks the council to invalidate the statute.” Also, they determined that Energy Northwest “must make specific plans for specific actions to achieve a specific goal — geologic or other approved sequestration of greenhouse gases — and receive from the governor a site certification agreement before it can ask for relief by the purchase of [carbon] offsets.” Though the PMEC plan is suspended, Energy Northwest may later propose a natural-gas-fueled powerplant with pre-fitting for possible later IGCC operation.
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“Suspension of the plan sends a chilling, likely unintended, message to future developers of power plants and other facilities considering investing and risking millions or billions of dollars in the regional economy,” said Energy Northwest spokesman Brad Peck. As Energy Northwest adjusts its PMEC plans, the Wallula Energy Resource Center (WERC) has applied for a site study with EFSEC. This privately-funded plant would be located in western Walla Walla County. According to the project’s Web site, IGCC and CCS technology used at WERC “will enable it to generate approximately 700 megawatts of electricity with very low CO2 emissions that meet or beat standards recently mandated by West Coast state governments.” If all goes as planned, WERC would like to begin construction in the fall of 2009 and commission the plant four years later, in the fall of 2013. WERC’s progress is largely dependent on the success of CCS testing currently underway in the basalt-rich ground beneath the Wallula site. If these tests show that CO2 stored there doesn’t migrate and escape into the atmosphere, then development of WERC will surely move forward with support from many — including many coal-reluctant environmentalists.
Coal’s new image Technological advances in coal technology stand to change not only public opinion about coal, but they may very well serve to unite those previously divided by environmental concerns. Those who related coal to pollution and undesirable environmental consequences are beginning to see coal’s cleaner, healthier image while others are looking forward to more affordable energy sources. This is exciting news for Washington, where advances in coal technology are setting an example for other states and, in a greater sense, the rest of the world.