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The presidential candidates keep talking about the evils of China's new coal plants and "clean coal technology" as a savior. What's the real story?

Published October 20, 2008 10:22AM (EDT)

Dear Pablo,

I keep hearing that China is currently building around one coal-fired power plant per week. Even the presidential candidates repeat it. Is it true? Do you know any sources for it? The candidates also keep talking about "clean coal." What's the story with that?

Good question. I have heard various figures from various sources, and some say the number is actually higher. According to John Ashton, the top climate change official at the U.K. Foreign Office, "China is now building about two power stations every week." Joel Blum, the John D. MacArthur Professor of Geological Sciences at the University of Michigan, says, "Coal-burning plants are being built in China at an alarming rate -- something like two per week."

In the vice-presidential debate, Joe Biden claimed, "China is building one to three new coal-fired plants burning dirty coal per week. It's polluting not only the atmosphere but the west coast of the United States. We should export the technology by investing in clean coal technology." So if foreign officials, college professors and even presidential campaigns are citing this figure, there must be something to it, right? Well, unfortunately, no one cites a firsthand source.

So let me go straight to the numbers. A simple way to estimate an actual number is to start by extrapolating the coal energy use by China to estimate the current annual demand growth. According to the U.S. Energy Information Administration, "at the end of 2005, China had an estimated 299 gigawatts of coal-fired capacity in operation." The administration also reports that "coal use in China's electricity sector is projected to increase ... at an average rate of 4.1 percent per year." At this rate, China now uses 337.3 gigawatts of coal-fired electricity and will be adding 13.83 gigawatts in the coming year. One gigawatt is equivalent to the capacity of a typical nuclear power plant!

Next we need to assume that the average coal plant in China is 300 megawatts (or 0.3 gigawatts), which is smaller than the standard size of a coal-fired power plant in the United States. (The average capacity of coal plants currently under construction in the U.S. is 570 MW.) By dividing 13.83 by 0.3, we find that China will need to build 46 plants in the next year! This comes out to almost one per week. While these numbers don't directly support the claims made in the media, there is evidence that that the average size of coal-fired power plants is smaller in China. If they averaged 140 megawatts each, the demand would indeed be around two per week. So, despite the lack of a firsthand citation, it looks like the statements you have heard are true.

What's also true is that the extensive use of coal by the Chinese for electricity generation befouls their air and affects air quality on the west coast of the United States. China's impact on climate change is global. In the U.S., we enjoy relatively stringent air quality requirements yet mercury emissions from coal-fired electricity are 48 tons annually! With China's widespread use of coal, and with its lack of air quality legislation and enforcement, the amount of mercury being spread around the globe is alarming.

But China is not the only country expanding its use of coal for electricity generation. So are we. Currently in the U.S., 29 coal-fired power plants are under construction, according to the National Energy Technology Laboratory. While the construction of several coal-fired power plants has been halted by courts because of environmental concerns, such unprecedented moves are not yet widespread enough to push the U.S. toward reducing coal emissions. Every new coal-fired power plant that we build will be on line for many years, and the cost of retrofitting them with new pollution control technologies may be prohibitive. This is why former vice president and climate crusader Al Gore has called for a moratorium on all new coal-fired power plant construction.

So does the solution really lie in "clean coal technology," as both presidential campaigns keep saying? As nice as it sounds, clean coal is an oxymoron of epic proportions, promoted by the coal industry, a sort of Orwellian doublespeak meant to introduce the notion that coal can be environmentally friendly.

If we apply the word "clean" to mean a decrease in the amount of criteria air pollutants, or emissions that result in locally unhealthy air quality, then, yes, clean coal is possible. This is achieved with the use of chemical processes, steam reformation and scrubbers to reduce the amount of sulfur dioxide, mercury and particulate emissions from the smokestack. What clean coal does not do is remove any carbon dioxide, the primary culprit behind climate change, from the emissions. This can be achieved only with carbon capture and sequestration technology, in which the greenhouse gas is piped into depleted natural gas fields and locked away indefinitely. Unfortunately this technology increases the cost per unit of coal-based electricity to erase its advantage over wind power, even with subsidies. So if you want clean air and a stable global climate, don't fall into the clean coal technology trap.

By Pablo Plastic

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