Coal | Energy | Climate change | Science & policy | Energy | Issues
Photo: Coal

Coal plant. (Credit:greenstonegirlpix via Flickr.)

The problems with coal

Burning coal to produce electricity seriously affects air quality, human health, wildlife and climate change.

• Coal is a major threat to our climate. Just one 150-megawatt coal-fired power plant can produce more than a million tonnes of greenhouse gas emissions per year. That's about the same as 200,000 cars produce.
• Coal-fired power is the leading source of mercury emissions in North America, which are dangerous to people, fish and wildlife. Fish may have thousands of times more mercury in their systems than is found in the surrounding water due to bioaccumulation. Wildlife species that rely on fish, such as eagles and osprey, also have high levels of mercury. Mercury is known to affect learning ability and neuro-development in children.
• Burning coal also produces large quantities of sulphur dioxide, nitrogen oxides and particulate matter. The Canadian federal government has declared particulate matter to be a toxic substance because it can cause breathing and respiratory problems, irritation, inflammation, damage to the lungs, and premature death.
• Sulphur dioxide in the air can also form into sulphuric acid and mix with rain or snow, creating acid rain. Acid rain can have drastic ecological impacts on lakes by changing the water's acidity, making the lakes uninhabitable for fish, plants and animals.
• Concerns about air pollution have prompted the Ontario government to commit to phasing out coal-fired electricity plants by 2014.

Coal-bed methane

Coal-bed methane (CBM) is similar in composition to natural gas (i.e., mostly methane), but it is found in and around coal seams. CBM is now being aggressively pursued in Canada as traditional supplies dwindle and demand for natural gas increases. The B.C. government is a strong advocate, offering significant tax breaks and policies to encourage exploration and development.

• Because CBM is trapped in rocks deep within the Earth, more work is needed to get it out, leading to greater environmental damage at the source.
• Large quantities of water—sometimes more than tens of thousands of litres per day—are first pumped from the coal seams in order to release the CBM. Pumping this much water (usually from many wells simultaneously) can deplete local water supplies. The water, which may be contaminated, must then be released. Surface disposal is often permitted, which can be harmful because the water is often laden with salts and chemicals that damage vegetation.
• Pumping the water from the seams releases the CBM, but there is no guarantee that it will all be vented up the designated well. CBM can travel through the coal seam and end up in the atmosphere where it acts as a powerful greenhouse gas, or can migrate into nearby water wells or houses, posing health risks to local communities.

http://www.davidsuzuki.org/issues/climate-change/science/energy/coal/

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