Clean Coal

Clean Coal

Clean coal is the name attributed to coal chemically washed of minerals and impurities, sometimes gasified, burned and the resulting flue gases treated with steam, with the purpose of almost completely eradicating sulphur dioxide, and reburned so as to make the carbon dioxide in the flue gas economically recoverable. 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' , with no specific quantitative limits on any emissions, particularly carbon dioxide.

The burning of coal, fossil fuel, is believed to be one of the principal causes of anthropogenic climate change and global warming. The concept of clean coal as a solution to climate change and global warming is claimed to be "greenwash" by some environmental organisations such as Greenpeace. Emissions and wastes are not avoided, merely transferred from one waste stream to another. The Australian of The Year, renowned scientist and author Tim Flannery has been reported as saying "Coal can't be clean".

There are no coal fired power stations in commercial production which capture all the carbon dioxide emissions and the process is theoretical and experimental or subject of feasibility or pilot studies. It is has been estimated that it will be 2020 to 2025 before any commercial scale clean coal power stations (coal burning power stations with Carbon capture and sequestration) commercially viable and widely adopted. This time frame is of concern because there is an urgent need to mitigate greenhouse gas emissions and climate change to protect the world economy according to the Stern report. Even when CO2 emissions can be caught, there is considerable debate over Carbon capture and storage.

The byproducts of clean coal 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 sulphur dioxide (SO2), nitrogen oxides (NOx) and particulate (PM) emissions from the coal burning process, carbon dioxide (CO2) emissions and radionuclides will be more difficult to address. Technology does exist to capture and store CO2 but they have not been made available on a large-scale commercial basis due to high economic costs.

Potential uses of clean coal
The primary example of clean coal is the proposed US FutureGen plant — planned to be a near zero-emissions coal-fired power plant, but which is years away from commercial operation (expected 2012) and whose commercial viability is unknown.

It is also believed that some process similar to the natural gas fuel cell or microbial fuel cell (charged from biomass or sewage) may be practical using coal as fuel. These technologies are used mostly for stationary fuel cells as charging is slow. A large power plant in a coal mine might be the most energy efficient approach and require the least transport of coal to the users and the return of the coal chute and the use in homes may be possible in some places. Especially if home sewage or natural gas lines can be tapped as well by an improved fuel reformer technology such as that used already to convert methanol or gasoline to the natural gas form.

Support and opposition
Clean Coal has been mentioned by United States President George W. Bush on several occasions, including his latest 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.".

In Australia, clean coal is often referred to by Opposition Leader Kevin Rudd as a possible way to reduce greenhouse gas emmissions. Current Prime Minister John Howard, however, believes that nuclear power is a better alternative, as clean coal technology may prove to be economically unfavourable.

Despite the supportive comments from U.S. President Bush about clean coal, the White House has only granted $18 million (USD) to develop zero-emission coal-fired power plants over the next decade out of a $388 billion omnibus spending bill.

In addition, some prominent environmentalists (such as 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". Complaints focus on the environmental impacts of coal extraction, the prohibitively high costs to sequester carbon, and uncertainty of how to manage end result pollutants and radionuclides. (Credit: Wikipedia).


Environmentalists and the Environment


Carbon Trading

Clean Energy

Tim Flannery