Cleaning It Won't Be Dirt Cheap

The Technology to Scrub Out Carbon Dioxide Is Within Reach, but It Costs Too Much Money and Consumes Too Much Energy
By JEFFREY BALL

Pleasant Prairie, Wis.
Big industry calls it the future. Al Gore suggests it's a fantasy. Whatever the truth about "clean coal," consumers will be paying for it one way or another.
Coal, more than any other fuel, powers the planet. It is the primary source of electricity in dominant economies from the U.S. to China to Germany. In all those places, coal is cheap and, unlike oil, domestically plentiful. Its use is rising, particularly in developing countries that soon will consume more energy than the industrialized world.

Coal's problem is that it is dirty. When burned, it spews out more carbon dioxide than any other fossil fuel. Globally, burning coal to make electricity is the biggest single source of man-made CO2 -- bigger than gasoline-powered cars and trucks. Governments world-wide are advocating massive cuts in greenhouse-gas emissions. It is hard to see how those cuts could materialize without clean coal.
Clean coal refers to the idea of harnessing the black rock's energy while safely disposing of the resulting CO2 rather than sending it skyward. In dueling television commercials, the power industry portrays it as a silver bullet nearly ready to be deployed, while environmental groups allied with Mr. Gore imply it's a smokescreen from a fossil-fuel industry under fire.
Right now, clean coal seems both possible and improbable. The basic elements of clean coal are already in use in small corners of industry. But whether it is broadly and quickly adopted around the world will depend less on science than on economics. Cleaning coal is very expensive.
Home to one of the world's most advanced clean-coal tests, the Pleasant Prairie power plant exposes the hyperbole on both sides of the debate. Fired up three decades ago, the plant has run full-bore ever since, adapting time and again to new environmental rules and still churning out some of the cheapest energy in the nation. It burns some 13,000 tons of coal daily to produce 13% of the electricity consumed by all of Wisconsin.
New rooms of machinery have been added to scrub a swirl of pollutants from the plant's exhaust before it is released into the air. Today, half as much space at the plant is devoted to preventing pollution as to producing power. That has slashed the plant's output of chemicals that cause respiratory disease and acid rain. But it has done nothing to trim the plant's emissions of CO2. This coal-fired power plant is cleaner than it once was, but it still isn't "clean." This plant pours out some 8.6 million tons of CO2 annually -- about as much as 1.7 million U.S. cars.
Is clean coal a real solution to Americas energy problems? WSJ's Jeff Ball goes to Pleasant Prairie, Wisconsin to examine a clean coal plant.
The first step in making coal more climate-friendly is for a power plant to capture most of its CO2. A handful of plants today capture small amounts of the gas for reasons unrelated to climate change. One in Maryland, for example, sells it for making soft drinks and beer, and for freezing food. One byproduct of power generation is steam, and the federal government offers incentives to plants that make more-efficient use of it. Steam is also used to capture CO2.
A year ago, the Pleasant Prairie plant entered this first phase with an experiment to capture its CO2. The machinery for extracting the gas here is three stories tall. But at the 425-acre plant, it seems tiny. Its pipes pull a bit of exhaust from the power plant and then remove the CO2 in a process that involves mixing the gas with ammonia.
So far, the test is grabbing only about 1% of the greenhouse gas the plant coughs out. The method still consumes too much energy, says Sean Black, a manager at Alstom SA, the French company managing the test. "We're just in the beginning of this process," he says.
The second step -- one not yet attempted here at the Wisconsin plant -- is to take the captured CO2 and dispose of it safely, perhaps by burying it. CO2 has been shot underground for decades in places like Texas, where it is injected into aging oil and gas fields to force the remaining fossil fuel up through wells. Some 30 million tons of CO2 are injected into oil and gas wells annually in the U.S., according to federal statistics. That is tiny -- less than 1% of the roughly six billion tons of CO2 the country annually exhales.
Howard Herzog, a leading clean-coal specialist at Massachusetts Institute of Technology, is a technological optimist and a political realist. He believes scientists can find ways to slash power plants' CO2 output just like they figured out how to slash those plants' output of pollutants that foul air and streams. But it will take a lot of money: MIT recommended in a recent study that the U.S. nearly quadruple its clean-coal spending, to $1 billion a year. And that is just for research.

It also will take patience. An anticoal backlash is gathering steam in the U.S., and Mr. Herzog worries it will block all new coal-fired power plants in the country, which could boost electricity prices. A rational compromise, he believes, would be to allow new coal-fired plants to keep their CO2 emissions at the same level as natural-gas-fired plants through the use of cleaning technology. That would amount to an emissions cut of about 50% below the level of a conventional coal-fired plant, while raising the cost of generation by 50%, Mr. Herzog figures. Consumers probably wouldn't see rate boosts that high, he says, because generating costs are only one factor in determining retail electricity rates.
Still, clean coal has proven too expensive before. Earlier this decade, the federal government launched a multibillion-dollar research program intended to build a carbon-free, coal-fired power plant. Last year, when the cost of that program nearly doubled to $1.8 billion, the government effectively shut it down.
The Pleasant Prairie power plant is a monument to the fickleness of the nation's energy priorities -- and to the stubborness of coal. Designed in the wake of sweeping 1970s federal environmental laws, the power plant was the first built by Wisconsin Energy Corp. to burn coal from Wyoming's Powder River Basin rather than from nearby Illinois or Appalachia. One reason is that Western coal is lower than the Eastern variety in sulfur, which forms a pollutant the laws capped.
At the time, Wisconsin Energy intended to build new nuclear plants, too. But Wisconsin effectively banned new nuclear-plant construction in the state. Without an alternative, Wisconsin Energy has run the Pleasant Prairie plant to crank out more power than originally planned. As the federal government has further toughened clean-air standards, the company kept adding pollution-scrubbing equipment to keep the plant alive.
The crackdown on CO2 is just the latest -- and biggest -- regulatory shift prodding more changes to the plant. On a recent frigid morning, in a scene that brought to mind an old whiskey still, one of the shiny pipes for capturing CO2 was shaking and clanging, and steam was pouring out the top. Alstom's Mr. Black said the contraption looked so jury-rigged because engineers had to modify it to resolve problems that cropped up.
That burst of steam could be the industry's last gasp. It also could be a fresh breath from an industry with plenty of life left.
Write to Jeffrey Ball at jeffrey.ball@wsj.com