Nuclear power generates electricity using the extreme heat created by splitting - fissioning - uranium atoms in a reactor. The heat changes water to steam, which turns a turbine connected to an electricity generator. To learn more about the process, have a look at this video.
Nuclear power generates a lot of electricity in Ontario, and a fair amount elsewhere in Canada. Most of Canada's nuclear power plants are in Ontario, but a few are in New Brunswick and Quebec. Another key point: Canada has the largest uranium deposit in the world.
What benefits make nuclear such a popular electricity source in Canada? And what are its drawbacks and negative environmental impact?
Nuclear power does not cause greenhouse gas emissions or air pollution
- During electricity generation, nuclear power does not release GHGs or air pollutants.
It's a reliable source of electricity
- Nuclear power is a non-intermittent source, so it can supply electricity constantly and reliably.
There are abundant supplies of uranium
- There are uranium deposits around the world, and only a small amount of uranium is needed to generate electricity in a nuclear power plant.
- Canada is the world's largest producer of uranium. Look at this World
Nuclear Association map to see the location of Canada's deposits.
Nuclear power has relatively little impact on the local environment during electricity generation
- Nuclear power generation results in a fairly low level of water pollution and land disruption under normal circumstances.
Drawbacks and Environmental Impact
There is no safe disposal of nuclear waste
- Nuclear power creates extremely harmful radioactive waste (used uranium), and there is no safe disposal method for it.
- The current method of dealing with nuclear waste is to put it in a canister and submerge it in a pond constructed for this purpose, or to contain it in a concrete cylinder. After 40 or 50 years, when its radioactivity begins to decay, the waste is buried underground. Look at this CBC report for a discussion on where Canada might bury its nuclear waste.
- Nuclear waste has a radioactive half-life of 250,000 years, which means that it remains extremely dangerous until the end of that period, posing grave risks to humans and the environment if exposed.
There are serious issues of safety and exposure during nuclear electricity generation
- Today's nuclear power plants employ improved technologies and stricter safety regulations, greatly reducing the risk of future accidents, but there is still the potential for serious catastrophe. In the past, nuclear accidents have resulted in death, serious illness, and extreme environmental damage, and their impact continues for generations. The worst accident was at the Chernobyl nuclear power plant in the Ukraine. See this BBC report for details on the damage and deaths it caused.
- Nuclear power plants routinely emit low level radioactivity that may pose cancer risks for nearby communities.
- Plants can also leak other hazardous materials.
Mining and transporting uranium is destructive
- Mining uranium is a dangerous process, exposing humans and the environment to radioactivity.
- Mining uranium contributes to water pollution and land damage. Mining disrupts, even destroys, the area being mined.
- The mining process results in both the deliberate routine release and accidental spill of contaminated water, leading to the potential poisoning of nearby waterways and threatening the local environment and human residents.
- GHGs are associated with the entire production cycle of nuclear power.
The construction of generation plants requires fossil fuels that
release GHGs, and the same is true when the uranium in those plants is
mined, enriched, and transported.
Nuclear power operations involve large quantities of water, as well as thermal discharge
Uranium is a non-renewable resource
- Huge amounts of water are needed for cooling the plant during operation, and to create steam to turn turbines.
- Water used for cooling is released back into the environment after cycling through the plant. This alters the temperature of the local body of water and
may harm or kill aquatic life. This is called thermal discharge.
- It doesn't take a lot of uranium to generate electricity, and plants need to be refueled only once a year, but there is a finite amount of uranium on the planet. Once it's gone it's gone.
Nuclear power plants are very expensive and take a long time to complete
- For example, the Darlington Nuclear Plant in Ontario cost $15
billion and took over ten years to build.
- Nuclear waste disposal is also extremely expensive. Canada estimates that it will need as much as $24 billion to dispose of its nuclear waste.
For more information:
Centre for Energy (2010). What is nuclear power? Available here.
David Suzuki Foundation (2010). Nuclear. Available here.
Natural Resources Canada (2009). Uranium/ Nuclear Energy. Available here.
U.S. Energy Information Administration. Energy Kids: Uranium (nuclear). Available here.
U.S. Environmental Protection Agency (2010). Nuclear Energy. Available here.
World Nuclear Association. Overview of Nuclear Energy. Available here.