Clean Electricity From Coal
Coal is a low cost, secure and abundant long-term fuel source on the planet. There are billions tones of coal reserves in the world, capable of generating more energy than oil, natural gas and oil sands combined.
Clean Coal Technologies For Clean Electricity
Coal-fired power plants are used by all countries in the world as one of the main source of electricity. It is estimated that 40% of global electricity is generated by coal. In countries such as China, Australia, Poland and South Africa, coal provides more than 75% of electricity. However, along with producing energy, burning coal releases harmful emissions, making coal-fired power plants one of the biggest sources of carbon emissions.
Clean coal is an umbrella term used to promote the use of coal as an energy source with technologies developed to reduce environmental impact. There are several technologies available now to reduce the environmental impact of coal energy generation. These technologies apply to various stages in the coal power plants with the purpose of reducing the amount of carbon emissions. One technology involves the chemical washing of minerals and impurities from coal. Another technology is the treating of flue gases with steam to remove sulfur dioxide. Carbon capture and storage technologies are to capture the carbon dioxide from the flue gas.
Cleaning Coal For Clean Electricity
Coal cleaning uses air and water to clean coal that was originally too dirty to burn. There are also related technologies to clean coal from acid rain, mercury and smog-causing agents. Acid rain causes sulfur dioxide at the smoke stack, thus reduce the energy efficiency of coal.
Coal Gasification For Clean Electricity
The main technology for turning coal into electricity without dumping excessive carbon dioxide into atmosphere is to “cook” the coal into a fuel gas: Carbon is removed while remaining hydrogen is burnt in a turbine. This technology uses a combination of heat, steam and pressure to turn the coal into a gas.
Through this process, carbon dioxide is being separated. Only clean hydrogen is burnt to make electricity and carbon dioxide is not released into the air. This clean coal plant could cut carbon dioxide emissions by as much as 90 percent.
Opponents note that carbon capture and storage technology has yet to be used or proven on such a large scale and that it may not be successful. There are also concerns that pumping sequestered CO2 into oil and gas wells to help make the fuels easier to pump out of the ground will lead to further consumption of fossil fuels, and CO2 emissions, thus adding to global warming.
Carbon Capture And Storage
In coal gasification process, it is theoretically possible to inject carbon captured back into the ground right on site. However, there are great concerns about the projected high costs of the process; the human health dangers of large, rapid releases of carbon dioxide back into ground and the global warming risk posed by small levels leakage over long periods.
In the past few decades, significant gains have been made in controlling sulphur dioxide, nitrogen oxides and mercury in the coal power plant. However, carbon dioxide remains a significant challenge for electrical utilities around the globe. Clean coal technologies are capable of bringing the resulting emissions of coal-fired electricity to near zero.
