Coal: The big challenge for US CO2 emissions

At NRG Energy’s coal-fired electricity plant in Thompsons, Texas, a train from the Powder River Basin coal mines of Wyoming pulls in after a five-day trip from Wyoming, loaded with more than 15,000 tonnes of coal.  It takes eight hours to unload the 130-car trains, and then the next train pulls in.

This plant burns 35,000 tons of coal on a hot day to provide electricity to cool area homes. And bulldozers must constantly shift the coal stockpiled in a giant mound under the hot, noonday sun to prevent combustion as it awaits its turn in the 2,200°F furnace.

Yet burning the coal to make electricity, transporting it 1,500 miles to the power plant and keeping it cool emits enormous amounts of carbon dioxide.

The US government estimates CO2 emissions from coal-fired electricity generation comprise nearly 80 per cent of total CO2 emissions produced by the generation of electricity in the US. Sixty to 80 per cent of coal is, in fact, carbon, making it the most carbon intense of all the fossil fuels. The Environmental Protection Agency has estimated the average US coal plant emits 4.6m metric tons of CO2 each year. And there are 600 coal-fired electricity plants across the country.

Out across the prairies of Wyoming, the scale of the emissions problem can be seen at the world’s biggest coal mine – the North Antelope Rochelle Mine, where workers dig out coal from among the biggest coal seams in the world – as deep as 80 feet and hundreds of feet wide. The chunks are then crushed to mere inches and loaded into trains to carry the coal to power plants across the country on what the industry has made America’s busiest railroad.

Demand is so high for coal, which fuels 50 per cent of US electricity production, that this process never stops. Day after day, workers like Bill Veal, at the Peabody mine, spend 12-hour shifts in their trucks, equipped with water tanks, refrigerators and microwaves to minimize interruptions, filling haul truck after haul truck. This one mine loads 15,500 tons of coal in up to 20 trains a day, rounded into neat piles inside car after car after car. And there are over a dozen mines in the area, known as the Powder River Basin, which supplies 40 per cent of the US’ coal.

Producers focus on CCS

This makes power producers, like NRG, more interested than most about the need for carbon controls. Steve Corneli, NRG’s senior vice president for market and climate policy, puts it this way:

Coal is really an important thing to get right as we address climate change. If we don’t find a way of reducing the carbon, while continuing to use coal, we won’t be successful in preventing climate change.

Gregory Boyce, chairman and chief executive of Peabody Energy, the world’s largest private-sector coal company, points to the cleaning up of other emissions from coal as proof the industry can tackle CO2  emissions, too. During the past four decades emissions such as sulfur dioxide and nitrogen oxides, have been reduced by more than 40 per cent.

Yet, in the time it takes to develop the technology needed to clean the CO2 emitted by coal, emissions will grow with rising demand for the fuel source. The International Energy Agency estimates coal use will grow 61 per cent by 2030. Boyce, therefore, concludes that carbon capture and sequestration is critical.

Duke Energy, a major power producer, has applied for a grant from the US government to fund one of the country’s first demonstrations of carbon capture and storage at a power plant. But it also has gone overseas, signing a memorandum of agreement with China Huaneng Group, that country’s biggest electric utility, to research clean energy solutions.

This move abroad highlights the difficulties power producers are having engaging the US public on the need to find an environmental solution to coal dependency, according to Teri Viswanath, coal analyst at Credit Suisse Research. She notes public resistance to new coal-fired plants has led to cancellations of two-thirds of the 150 planned projects in the US over the past few years, but that has just meant more 50-year-old, heavily polluting plants will remain in production and likely break down, straining electricity supply.  Viswanath says that what concerns her is that the dialogue about coal in the US has stopped.

The public is focused on renewables, but the energy industry believes it also important to increase efficiency and the US’ energy supply with sources such as new nuclear and natural gas supplies, while cleaning up coal. With US energy demand expected to grow 26 per cent from 2007 to 2030, it is often said the US is going to need all the energy it can get.

Storage concerns

Victor Der, principal deputy assistant secretary for Fossil Energy in the Obama Administration, believes the storage issue is the one that needs to be addressed for the long term. He optimistically runs through how it will work. Various technologies exist to capture carbon, and the industry knows how to transport it in pipelines. Partially saline-filled reservoirs are best for storage, as CO2 is almost a liquid when captured. When injected into the reservoir, filled with wet sandstone in saltwater, it will seep into the pore spaces in the formation and over time react with minerals to become solid. These reservoirs are several thousand feet below ground, with an overburden of solid cap-rock 500 to 1,000 feet thick forming a natural seal.

Der confidently notes that there is naturally occurring CO2 underground, and it has been there millions of years. And the US is not along: Australia and several European countries are also doing research, and they share ideas through the Carbon Sequestration Leadership Forum. The oil industry has for years pumped CO2 into the ground to force out oil. But it has not attempted to safely transport carbon in large volumes all over the country and sequester it indefinitely. Analysts say doing so might cause earthquakes or even result in dangerous leakages that require laws to regulate and apportion blame.

Cost concerns

Even if it can be done without negative repercussions, there is no guarantee carbon capture and sequestration technology will become commercially available at an economic price, providing for its widespread adoption. Nonetheless, it seems that has become the best hope for the US government.

So scientists in Obama Administration are researching the carbon capture and sequestration process, modelling the impacts of capturing and storing the CO2 underground in drained oil and gas fields, saline formations and coal seams that cannot be mined. The US Energy Information Administration predicts if no action is taken, the US will emit approximately 7,550m tons of CO2 per year by 2030, increasing 2005 emission levels by more than 14 per cent.

Here to stay

The industry estimates the Wyoming basin has 100-150 more years worth of production, based on today’s technology. And there are other basins across the country, giving rise to government estimates of several hundred years worth of coal still to be recovered in the US – the Saudi Arabia of coal as the world’s biggest resource holder with 27 per cent of the world’s known coal reserves.

Addressing emissions from coal is a global issue: while the US has big reserves of coal China is the biggest user. Looked at globally, coal produces a little over a quarter of the world’s energy and nearly 40 per cent of its greenhouse gas emissions, according to Blackout, by Richard Heinberg, senior fellow of the Post Carbon Institute in California. Der notes that the magnitude of the demand for electricity on a global basis makes it difficult to move away from coal.

Yet Howard Herzog, senior research engineer at the MIT Energy Initiative, fears the government is going to miss the opportunity to get a handle on carbon emissions from coal before going to Copenhagen for the Climate Change Summit in December. He says that coal is the issue that must be dealt with.

The Obama Administration has said it wants to reduce carbon emissions 80 per cent by 2050, reaching a consensus on July 8 with other G8 countries – Britain, Canada, France, Germany, Italy, Japan and Russia. It also agreed to work with other countries to cut global emissions in half. Yet Herzog questions how that goal will be met:

There’s a real gap between hitting that goal and the policies they’re putting place. As long as it’s free to put CO2 in the atmosphere, no one is going to take it out of the chimney and put it into the ground. You need to change that behavior.

Congress does not appear prepared to take a strong enough stance at this point. The Waxman-Markey climate bill now under consideration in the Senate, devotes $60bn to taxing power distributors to fund carbon capture and sequestration demonstration projects and gives 10-year breaks, as enticements, to those that do capture and sequester most of their emissions.

However, only coal-fired power plants licensed after 2015 will be forced to adhere to emissions standards of 1,100 pounds of CO2 per megawatt-hour. And those licensed after 2020 will be capped at 800 pounds of CO2 per megawatt-hour. That means none of the 15 coal plants being built today, or the 600 already in operation, will be under those restrictions as the US undergoes the largest build-out of new coal in the past 20 years.

Nonetheless, Herzog says, if Waxman-Markey passes as is, that would be a significant step, as existing coal plants would still be subject to a carbon price, and incentives for carbon capture and sequestration in the bill would encourage some to retrofit.

Seventy per cent of the US’ coal fleet came online before 1980, so a third of the units operating today are more than 40 years old and do not have top of the line environmental controls. In fact, 38 per cent of the capacity that is over 40 years old lacks equipment to control emissions of even sulphur dioxide or even nitrogen oxide. Yet there is widespread pessimism that any such carbon legislation will be passed anytime soon.

In the meantime, mandating energy efficiency measures would go a long way toward helping to curb carbon emissions. Yet some say efficiency is not being pursued more aggressively. Herzog sums it up:

This is a real hard sell. I don’t think the general populace sees the urgency.

Will any of these measures will be forced, one wonders, in time to have a real effect?

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