Greenhouse Gas Emissions
What is the Greenhouse Effect?
Naturally occurring gases in the atmosphere help regulate the earth's temperature by trapping solar radiation. This is known as the greenhouse effect. Human activities such as agriculture and the burning of fossil fuels (coal, oil and gas) produce additional greenhouse gases, which are accumulating in the atmosphere. Scientists believe the build up of these gases is causing an "enhanced" greenhouse effect, which could cause global warming and climate change.
The major greenhouse gases include water vapour (the most important), carbon dioxide (the second most important), methane, nitrous oxide, hydroflourocarbons, perflourocarbons, and sulphur hexaflouride.
Coal and Greenhouse Gas Emissions
Greenhouse gases from coal (mining and power generation) globally contribute around 25 per cent to the enhanced greenhouse effect. In Australia, around 90 per cent of coal's greenhouse gas emissions arise from power generation.
Coal is just one of many sources of greenhouse gases generated by human activity. Others include oil and natural gas, agriculture, land clearing and waste disposal.
Reducing Greenhouse Gas Emissions
Meeting the needs of an increasingly energy hungry world, while at the same time reducing emissions of greenhouse gases, is one of the major challenges facing humanity in the 21st Century.
Rapidly increasing world energy demand will ensure that coal remains a vital energy source for electric power generation and the metallurgical industries for many decades.
Australian producers are working hard to reduce emissions of greenhouse gases associated with mining operations. Major sources of greenhouse gas emissions associated with coal mining are fuel used in the actual mining operations, CO2 emissions from electricity, steel and cement production, and coal-seam methane released when coal is extracted.
It is not the use of coal, but how coal is used that must be the focus for action.
To meet growing global demand, coal production is projected to rise by almost 60 per cent by 2030. Around 90 per cent of this increase comes from rapidly developing economies. For example, China will almost double its output, India’s production more than doubles, and Russian production jumps by nearly 75 per cent.*
Ceasing the use of coal and other fossil fuels in order to cut greenhouse gas emissions is simply not a realistic option for the foreseeable future.
One of the most promising long-term solutions for reducing global greenhouse gas emissions from power generation is carbon capture and storage technology. It involves capturing the carbon dioxide (CO2) from large, stationary sources such as coal-fired power plants, compressing it for transport to an injection site, and then storing it safely and permanently deep underground.
Improvements in mining efficiency, tree planting associated with the rehabilitation of exhausted mine sites, and increased capture and use of coal-seam methane, are some of the strategies being employed to reduce fugitive emissions from mining operations.
Research and development is the key to reducing or eliminating greenhouse gas emissions from mining and use of coal.
As with most other areas of human endeavour, the technology associated with coal is dynamic, not static. The pace and range of research into coal-based greenhouse solutions is accelerating.
Advances in technology, particularly in the area of CCS, will ensure that the coal plants of tomorrow will be very different from those of today.
To learn more about low-emissions coal technology, visit www.newgencoal.com.au.
*(Source: International Energy Agency, World Energy Outlook 2008)