Clean coal technology

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Clean coal is a term used to describe methods and technologies intended to reduce the environmental impact of using coal as an energy source. These efforts can include chemically washing minerals and impurities from the coal, Gasification, treating the flue gases with steam to remove sulfur dioxide, and other proposed technologies to capture the carbon dioxide from the flue gas. The coal industry uses the term "clean coal" to describe technologies designed to enhance both the efficiency and the environmental acceptability of coal extraction, preparation and use[1], with no specific quantitative limits on any emissions, particularly carbon dioxide.

The burning of coal, a fossil fuel, has been shown to be one of the principal causes of anthropogenic climate change and global warming, according to the United Nations Intergovernmental Panel on Climate Change.[1] The concept of clean coal is said to be a solution to climate change and global warming by coal industry groups, while environmental groups maintain that it is greenwash, a public relations tactic that misrepresents coal as having the potential to be an environmentally acceptable option. Greenpeace[2] is a major opponent of the concept because emissions and wastes are not avoided, but are transferred from one waste stream to another. The 2007 Australian of the Year, paleontologist and environmental activist Tim Flannery made the assertion that "Coal can't be clean".[3]

It is has been estimated that it will be 2020 to 2025 before commercial-scale clean coal power stations (coal-burning power stations with carbon capture and sequestration) are commercially viable and widely adopted.[4] This time frame is of concern to environmentalists because of their belief that there is an urgent need to mitigate greenhouse gas emissions and climate change, according to the Stern report. Even when CO2 emissions can be caught, there is considerable debate over the necessary carbon capture and storage that must follow.

Byproducts

The byproducts of coal combustion are very hazardous to the environment if not properly contained. This is seen to be the technology's largest challenge, both from the practical and public relations perspectives.

While it is possible to remove most of the sulfur dioxide (SO2), nitrogen oxides (NOx) and particulate (PM) emissions from the coal-burning process, carbon dioxide (CO2) emissions and radionuclides [5] will be more difficult to address. Technologies do exist to capture and store CO2, but they have not been made available on a large-scale commercial basis due to the high economic costs.[6] For this reason renewable energy sources may be a more cost-effective and environmentally friendly alternative.

Potential cost of clean coal

In Carbon capture and storage under "Cost of CCS" lifetime costs for natural gas, pulverized coal and IGCC with and without carbon capture are detailed.

A 2003 study conducted by the International Energy Agency (IEA) on Greenhouse gases, found that the cost of building a shell-designed IGCC that doesn't capture carbon could cost $1,371 per kW. A comparable system that captures carbon could cost $1,860 per kW."[7]

Support

In the United States, Clean Coal has been mentioned by United States President George W. Bush on several occasions, including his 2007 State of the Union Address. Bush's position is that clean coal technologies should be encouraged as one means to reduce the country's dependence on foreign oil. Senator Hillary Clinton has also recently said that "we should strive to have new electricity generation come from other sources, such as clean coal and renewables."[8]

In Australia, clean coal is often referred to by Prime Minister Kevin Rudd as a possible way to reduce greenhouse gas emissions.[2] The previous Prime Minister John Howard has stated that nuclear power is a better alternative, as clean coal technology may not prove to be economically favorable.[9]

A clean coal carbon dioxide sequestering plant called Futuregen was planned to be built in Mattoon, Illinois to go online by 2013 as a demonstration and to add to United States energy production.[10] However, after the Illinois site was announced, Energy Secretary Samuel Bodman reversed the decision and US Federal government withdrew funding. [11] The project is now in doubt although there is still support for by industry backers and members of Congress.

Criticism

Prominent environmentalists, including Dan Becker, director of the Sierra Club's Global Warming and Energy Program, believe that the term clean coal is misleading: "There is no such thing as 'clean coal' and there never will be. It's an oxymoron."[12]

I say this based on my experience as the former head of the TVA, which bought and burned more than 30 million tons of coal a year. I was deeply involved in the strip mining, underground mining, trucking, and most importantly, the burning of huge quantities of coal. No one who has been deeply involved with coal can rightfully say it is clean.

— S. David Freeman in "Winning Our Energy Independence: An Energy Insider Shows How"

Complaints focus on the environmental impacts of coal extraction, high costs to sequester carbon, and uncertainty of how to manage end result pollutants and radionuclides.

There are other forms of clean and renewable energy such as solar, wind and hydroelectric which are supported by many of the environmentalist groups and campaigns.

Critics of the planned power plants assert that there is no such thing as "clean coal" and that the plant will still release large amounts of pollutants compared to renewable energy sources such as wind power and solar power. They also point out that the continuing construction of coal-powered plants (whether or not they use carbon sequestration techniques) encourages unsustainable mining practices for coal, which can strip away mountains, hillsides, and natural areas. They also point out that there can be a large amount of energy required and pollution emitted in transporting the coal to the power plants. Some people contend that sequestration technology has yet to be used or proven on such a large scale and that it may not be successful, lead to unexpected geological instability, contaminate groundwater supplies, and that sequestered CO2 may eventually "leak" up through the ground. There are also concerns that plans to possibly pump some of the sequestered CO2 into certain oil and gas reserves to help make the fuels easier to pump out of the ground will lead to increased concentrations of CO2 in potential fuel supplies which would have to be burned off during the refining process, thus adding to global warming.[13]

Based on the predicted combustion of 12,580 million tons worldwide during the year 2040, cumulative releases for the 100 years of coal combustion following 1937 are predicted to be[3]: 828,632 tons of Uranium and 2,039,709 tons of Thorium.

See also

Notes and references

  1. ^ AustralianCoal.com.au - Clean Coal Overview
  2. ^ GreenPeace.org - Clean Coal Myths and Facts
  3. ^ Herald Sun, Melbourne Australia February 14, 2007 04:30pm
  4. ^ David Brockway, Chief of the Energy Technology Division, CSIRO, quoted by Crikey.com.au 20 Feb 2007
  5. ^ ORNL.gov - Coal Combustion: Nuclear Resource or Danger?
  6. ^ BBC.co.uk - Clean coal technology: How it works
  7. ^ Parliamentary Office of Science and Technology (2005). "Cleaner Coal" (PDF). Retrieved 2007-04-23.
  8. ^ Remarks of Senator Hillary Rodham Clinton to the Cleantech Venture Forum VIII
  9. ^ NineMSN.com.au - Interview: John Howard February 11, 2007
  10. ^ http://www.csmonitor.com/2007/1219/p02s01-usgn.html accessed=11 July 2008
  11. ^ http://www.ens-newswire.com/ens/jan2008/2008-01-31-03.asp accessed=11 July 2008
  12. ^ Grist.org - Coal Position
  13. ^ ‘Clean coal’ push concerns environmental activists

External links

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