Monday, February 12, 2007

Coal and Electric Power Generation

In an earlier post, I noted that Electric Power Generation was the largest source of CO2 emissions: in the U.S. it accounts for about 40% and worldwide about 38%. This week I'll review the main sources of electric power, some technologies being developed to clean up power generation, and the political challenges that lie ahead. As in previous weeks, I'll argue that while technological developments are vital, the U.S. needs to show leadership in the area of conservation. While the developed world may be slowly waking up to the threat posed by climate change, we need to lead by example and demonstrate to the emerging economies of India and China, that conservation need not translate to slower economic growth.

Electric Power Generation
How does the U.S. generate electricity? Unfortunately, half of the total electric power generated still comes from coal:

(To enlarge a particular image, click on it.) Renewables accounted for a mere 2%! But at least Renewables have grown the fastest, right? Actually, Natural Gas is the fastest growing source of Electricity, while the growth in Renewables was just on par with the growth in Nuclear and Coal:

Does the importance of Coal in the Electric Utility sector explain why the U.S. has not signed on to the Kyoto Protocol? The OECD countries (Europe + North America + Japan + Korea + Austalia +NZ) collectively, rely less on Coal:

Meanwhile, the two most populous countries and their surging economies, are even more heavily dependent on Coal:

Close to 80% of all electricity in China is generated from Coal! But with China (and India) one always needs to factor in their pace of growth. Warning, the statistics cited below are mind-blowing:
China’s soaring economic growth has been headlined in recent years by a single, attention-grabbing statistic: China each year adds new power generating capacity equal to the UK’s entire electricity grid. But China surpassed this benchmark last year, according to new figures released quietly at the end of January by the China Electric Power News, the mouthpiece of the state industry. The paper reported that new power capacity in 2006 had expanded by 102 gigawatts, or roughly equal to the entire capacity of the UK and Thailand combined, or about twice the generating assets of California, the state with the biggest economy in the US.
... Just less than 90 per cent of the new plants are powered by coal, an inevitable result of a rapid build-up in capacity. Hydro power accounted for 10 per cent and new nuclear plants about 1 per cent.
Even if the share of Coal drops to 50% in both China and India, which would be remarkable given their current dependence on coal, their growth rates translates to a lot more Coal powered utility plants over the next decade.

Based on the numbers above, Coal will be a major source of electricity for years to come. More environmentalists are realizing that eliminating coal completely is a difficult proposition:
Like it or not, a future without coal is politically implausible in the near term, says David Hawkins, director of the climate program at the Natural Resources Defense Council: "While as a technical matter we could run the world's economy without coal, as a political matter it is not going to happen fast enough. The fuel's abundance and low cost make it something that most political leaders are unwilling to give up. We must do everything we can to accelerate our use of renewables, but the renewable-energy future is far too slow in coming to put all our eggs in that basket," Hawkins argues. "We have to start reducing greenhouse gases before we phase out fossil fuels."
The problem at least appears manageable: install technology at the Electric Utilities to reduce or eliminate emissions. While one need only deal with a fixed number of locations, it still requires technologies that are expensive to develop and deploy. The U.S. will most likely be at the forefront of "Clean Coal" technologies. America is the "Saudi Arabia of Coal", with 27% of all known coal reserves, and Business Leaders in the U.S. are starting to see the business potential of "Clean Coal".

Clean Coal and Carbon Sequestration
What exactly is "Clean Coal"? To address that question, we need to understand some basic facts about coal. Besides generating CO2 emissions:
... coal is as filthy as it is cheap and abundant. When burned it releases three pounds of sulfur dioxide and four pounds of nitrogen oxide for every megawatt-hour of operation. The nation's plants produce a total of about 48 tons of mercury annually.
One promising form of Clean Coal is:
... integrated gasification combined cycle—a mouthful usually shortened to IGCC. Unlike conventional coal-fired generators, IGCC plants don't actually burn the coal itself; they convert it into gas and burn the gas. This highly efficient process makes it possible to selectively pull out the resulting emissions, including carbon dioxide, which could then be collected and buried rather than released into the air.
... IGCC technology also gives engineers unprecedented control over what happens to the different components of coal after they go into the power plant. In normal coal-fired plants, nearly all the pollutants go up the smokestack, where some of them are captured from the exhaust by scrubbers. Here they never even hit the flame. Conventional plants burn pulverized coal in the air, which contains about 78 percent nitrogen. Since the burning takes place at low pressure, the carbon dioxide is diffuse; isolating it is difficult and expensive. Burning gasified coal in pure oxygen at high pressure concentrates the carbon dioxide, making it far easier to capture.
What happens to the CO2 emissions? Technologies which address this problem fall under the emerging field of Carbon Sequestration:
... In September 2005, the Intergovernmental Panel on Climate Change, a United Nations organization that includes scientists from nearly every country in the world, released a report estimating that 2 trillion tons of carbon dioxide could be stored in old coal mines, abandoned oil and gas fields, and in various other geologic formations around the world. That's a huge reservoir, even compared to the rate at which humans are now burning fossil fuels. "The estimated storage capacity equals about 80 times the total rate at which we make carbon dioxide from everything per year," Robert Socolow, a Princeton University physicist who coheads its Carbon Mitigation Initiative. Coal-power plants account for about 25 percent of that carbon dioxide, so it's 320 years of coal-power emissions."
Three large-scale carbon storage, or sequestration, projects are testing ways to bury carbon dioxide effectively. The world's oldest carbon-sequestration experiment began in the North Sea oil fields in 1996. Statoil, the Norwegian national oil company, extracts carbon dioxide from natural gas and pumps 2,800 tons of it every day 3,000 feet below the North Sea floor, trapping it in sandstone. A 250-foot-thick layer of shale covers the entire sandstone formation, and it seems to be leakproof. Statoil estimates that all the carbon dioxide emissions from every power plant in Europe for the next 600 years could be stored in the formation.
Of course these promising technologies will translate to added costs to the Utility companies. Consumers, Politicians and Business leaders need to put pressure on the Utilities to start investing in these technologies. This is an issue that requires more legislative and media attention. Unfortunately, Clean Coal has nowhere near the amount of media coverage as Corn Ethanol.

Don't Forget About Conservation
I have consistently argued that Conservation is something we in the U.S. must do more of. We need technologies to produce "clean" energy, AND technologies that drastically reduce the amount of energy we use. Ideally, we would combine technological advances with voluntary reduction in consumption. In a previous post, I highlighted the states that consumed the least amount of electricity per capita:

Besides being blessed with great weather, California is also the one state were bipartisan consensus has led to longstanding conservation programs.

Coal Industry Awakens
Exploiting calls for "energy independence", the coal lobby is pushing coal as another domestic fuel source. A recent article in the Wall St. Journal (subscription required) touched on the critical need to consider global climate change as part of any energy solution:
... Greater use of liquid fuels made from coal, the nation's most plentiful energy source, would reduce reliance on imported oil. But making the liquid fuels and burning them in automobile engines would release additional carbon dioxide, a greenhouse gas thought to accelerate climate change, environmentalists say.
... David Hawkins, a climate-change expert for the Natural Resources Defense Council, says the diesel fuel still contains carbon dioxide, which will be released into the air when it is burned in the engines of cars and trucks. "This issue is the classic example of why you need to have an integrated policy on both global warming and energy," he says.
Finally, to understand the importance of coal in the 2008 Presidential Elections, we note that the swing state of Ohio, and Iowa (the home of the first primaries) have a lot of coal reserves:

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