Update: On July 14, 2011, it would table plans to build a carbon capture and sequestration project at its Mountaineer Plant in West Virginia, which is mentioned in this article.
Coal is pretty amazing stuff. A single fist-size lump of bituminous coal contains about 12,000 Btu--enough energy to power a 75-watt bulb for two days. It's relatively easy to dig out of the ground and dirt-cheap: about one-sixth the cost of oil or natural gas per Btu. Most of the modern industrial world we see around us was built with coal power.
But coal has issues. Each lump can contain large amounts of sooty particulates, sulfur and nitrogen compounds (which cause acid rain), and traces of mercury and other toxic metals. Although coal-fired power plants are cleaner than they used to be, they are still bad news for the environment and human health. A recent study concluded that coal emissions contribute to 10,000 premature deaths in the United States each year. And coal is by far the largest single source of greenhouse gases in the U.S. So it is no surprise that coal has long been the primary target of proposals to cut air pollution and carbon-dioxide emissions.
Until now. Just in time to skirt the various plans to cap or tax CO2, coal is getting rebranded. The new buzzword is "clean coal"--and it's being portrayed as the high-tech, low-emissions fuel of the future. Senators John Kerry, D-Mass., and Lindsey Graham, R-S.C., recently wrote a New York Times op-ed piece calling for the United States to become the "Saudi Arabia of clean coal." U.S. energy secretary Steven Chu has called on his counterparts around the world to promote the "widespread affordable deployment" of clean-coal technology. A current climate bill in the U.S. Senate proposes a complex regime of taxes and subsidies intended to cut America's greenhouse gas emissions by 20 percent by 2020. But the bill effectively gives the coal industry a pass on cutting emissions until "sufficient commercial-scale" clean-coal technology has been deployed. Why try to reduce our dependence on coal today, the reasoning seems to be, when fabulous, guilt-free clean coal is just around the corner?
There's just one problem with this scenario: Coal will never be clean. It is possible to make coal emissions cleaner. In fact, we've come a long way since the '70s in finding ways to reduce sulfur--dioxide and nitrogen-oxide emissions, and more progress can be made. But the nut of the clean-coal sales pitch is that we can also bottle up the CO2 produced when coal is burned, most likely by burying it deep in the earth. That may be possible in theory, but it's devilishly difficult in practice.
Carbon dioxide is not some minor byproduct of coal combustion. Remember your high school chemistry: When coal burns, oxygen from the air combines with the carbon in the coal in an exothermic (heat-releasing) reaction. Because of the addition of oxygen, the resulting CO2 weighs more than the carbon alone--which means that each pound of coal produces about 2.5 pounds of CO2. Keeping that CO2 out of the atmos-phere requires a process known as carbon capture and sequestration (CCS). It works by forcing the exhaust from a power plant through a liquid solvent that absorbs the carbon dioxide. Later, the solvent is heated to liberate the gas, much the way a bottle of soda releases its dissolved CO2 when opened. The CO2 is then compressed to about 100 times normal atmospheric pressure and sent away for storage.
So far, so good. But CCS has two major hurdles. First, it consumes energy--a lot of it. While estimates vary, a coal-fired power plant would have to burn roughly 25 percent more coal to handle carbon sequestration while producing the same amount of electricity. That would mean a vast expansion in mining, transportation costs and byproducts such as fly ash.
But that's the easy part. The harder challenge would be transporting and burying all of this high-pressure CO2. American Electric Power recently began a CCS project at its Mountaineer Plant in West Virginia. The operation captures a few hundred tons of CO2 a day. That's a start--but a typical 500-megawatt power plant produces about 10,000 tons daily. Collectively, America's coal-fired power plants generate 1.5 billion tons per year. Capturing that would mean filling 30 million barrels with liquid CO2 every single day--about one and a half times the volume of crude oil the country consumes. It took roughly a century to build the infrastructure we use to distribute petroleum products. Could we build an even bigger CCS infrastructure of pumps, pipelines and wells quickly enough to hit the ambitious targets the climate bill envisions? Serious plans to engineer--much less finance--such a vast project aren't even on the table.
Here's a final problem: We don't know if the gas will stay buried. We could easily spend hundreds of billions injecting CO2 into the earth only to have it start leaking out again in a few decades. None of this means that CCS is impossible to achieve. But it is a dangerous gamble to assume that it will become technically and economically feasible any time soon.
At the moment, the Senate's climate bill is on the back burner. And many Americans remain dubious about both the causes and the appropriate solutions for global warming. (Recent revelations that several climate scientists apparently tried to squelch legitimate debate certainly don't inspire confidence.) But concern over greenhouse gas emissions will continue, and the pressure to regu-late them is growing. Wouldn't it be a shame if we created a policy that burdens American consumers with higher energy prices and yet does virtually nothing to reduce our CO2 emissions? By embracing the clean-coal myth, that lose-lose scenario may be exactly what we stand to achieve.
Sadly, although it might make little economic or scientific sense, the political logic behind clean coal is overwhelming. Coal is mined in some politically potent states--Illinois, Montana, West Virginia, Wyoming--and the coal industry spends millions on lobbying. The end result of the debate is all too likely to resemble Congress's corn-based ethanol mandates: legislation that employs appealing buzzwords to justify subsidies to a politically favored constituency--while actually worsening the problem it seeks to solve.
The focus on mythical clean coal is particularly frustrating because practical, cost-effective alternatives do exist--and I don't mean just wind and solar power. Natural gas is plentiful in the U.S., and gas-fired power plants produce only about half as much CO2 as coal. Not only that, but once it's ready, the CCS technology envisioned for coal plants would be even more effective if used with natural gas. Tiny gas-fired cogeneration plants in individual homes could also help. Because these mini electrical generating systems use their waste heat to drive the homes' climate control systems, they avoid the huge energy losses involved in making power at distant facilities. This technology exists today. Nuclear power is another proven, low-CO2-emitting option--and despite public fears, U.S. nuclear plants have been paragons of safety compared to the harm done by coal-fired plants.
The cleanest energy option of all is also the closest at hand: conservation. As clean-energy guru Amory Lovins has shown, its almost always -cheaper to save energy than to mine or drill for it. And there are still massive efficiencies to be found almost everywhere energy is used. Boosting incentives for insulation, next-gen LED lights and ultraefficient smart appliances could do more than carbon sequestration to reduce CO2 emissions in the coming decades.
Let's be clear. We should continue research into making coal cleaner--that fuel will be a vital part of our energy mix for decades. But let's not allow clean-coal myths to divert us from real-world energy alternatives that work today.