Canada has always been on the front line of nuclear innovation ever since the first line of nuclear plant technologies started developing in the 1940s. Today, 16% of Canada’s energy comes from nuclear reactors.
But in recent years, technological advancements and an increasing concern for the environment caused renewables to substantially drop in price per Watt. One of the renewables, solar energy,
seems destined for stardom in the energy industry. But what would be the impact of moving
from nuclear to solar energy in Canada? More importantly, can we compare the long term
environmental footprint of both? This can be answered by looking at the form of waste produced
over time by each energy transformation process.
It is important to note that the main environmental footprint comes from the nuclear waste
produced. This waste is cooled down in water-filled ponds and then stored in containers.
The first potential issue comes from the ponds. The water ponds are usually kept below 50͒C.
Prolonged interruption of the cooling process can result in water boiling and releasing radioactive
elements in the atmosphere. This happened in Fukushima. Even considering the dangers, plants
have been fortified against such dangers and the chances of something going wrong are very
low.   The radioactive waste is usually transferred after some years into containers.
Since large volumes of waste are displaced in thin-walled concrete containers and these containers
need to be carefully fitted underground, there is a chance of the vessel developing cracks, spilling,
or even breaking. 
“Scratches on the canisters open up new surfaces that are vulnerable to
chemical reactions. And that could result in corrosion cracking in the long term.” 
- Tom English and Subrata Chakraborty, Physicists
The canisters are also stored in dry places underground, but the rise of the sea level every year
might affect existing storage locations and force a relocation. Every movement of the canister
can potentially damage it further. Sensors are normally used to detect damage but not all plants
have them installed. Decommissioning nuclear facilities can also result in spills, but, as with all
the risks mentioned, if preparation and safety measures are put in place, the risk is minimized.
The latest pond/container recorded spill dates back to 1979, showing how safe the current
infrastructure is.  
To keep the matter specific, we will focus on photovoltaic cells. Unless damaged, photovoltaic
cells do not produce any waste or pollution during operation.  The critical component of panels
is made of silicon-containing materials. However, 90% of solar panels is actually composed of glass,
with traces of heavy metals and toxic elements.  The main concern with photovoltaic cells is
when they reach the end of their lifetime. There hasn’t been much work done on recycling
decommissioned or broken solar panels. Thus, solar panels are simply disposed of without their
material being recycled.  “[Solar panels] cannot be recycled…due to impurities. Common
impurities…include lead, cadmium and antimony.”- Dustin Mulvaney, Professor of
Environmental Studies, San Jose State University  The cost of recycling solar panels is so
high that it negates the purpose of this resource. A lack of proper recycling has led to disposal
of 250,000 metric tonnes of solar waste worldwide as of 2016, with a projection of 78 million
metric tonnes by 2050.  This waste is not radioactive, but still contains toxic elements that
need to be contained. For instance, cadmium, a carcinogen, can be washed off during rain when
exposed; the runaway water poses a threat to the surrounding soil and nearby population. 
It is very easy for solar panels to break and release their chemicals into the environment.
In regions prone to storms, entire solar farms can be destroyed.
“Leaching [cadmium] from broken panels damaged during natural events — hail storms,
tornadoes, hurricanes, earthquakes, etc. — and at decommissioning is a big concern.”
- Sean Fogerty, Environmental Scientist 
There are many other factors to take into account. The extraction of the Uranium could sometimes
release more carbon dioxide than a nuclear reactor could pay back in its entire lifetime. 
Considering the geographical location of Canada, it may not be as feasible to install solar panels
as it would be in, say, California. However, looking at waste alone, it’s evident that Canada is
not yet ready to implement a sustainable, economical solution for recycling solar waste. On the
other hand, nuclear waste, although not recyclable, is disposed properly such that the toxic waste
is not exposed to the environment. Considering their smaller lifetime, low efficiency, and their
high material consumption, solar energy loses the battle against nuclear (for now). With
technological advancements in the future, solar energy will likely catch up and overtake
nuclear energy; until then, it’s best to stick with our reactors.
For a bit more drops of future:
 GreenMatch, “The Opportunities of Solar Panel Recycling: What Happens to PV Panels When Their Life Cycle
Ends”, United Kingdom, Mar 2019. URL:
https://www.greenmatch.co.uk/blog/2017/10/the-opportunities-of-solar-panel-recycling (Consulted 15/03/2019)
 Verge Science, “88,000 tons of radioactive waste – and nowhere to put it”, San Onofre, Aug 2018.
URL: https://www.youtube.com/watch?v=YgVyPwhkoJs&t=64s (Consulted 14/03/2019)
 Crowley, K., “Are Nuclear Spent Fuel Pools Secure?”, Council on Foreign Relations, Jun 2005.
URL (Consulted 14/03/2019)
 KPBS TV, “Evening Edition Nuclear Waste Interview”, San Diego, Jan 2019.
URL: https://www.youtube.com/watch?v=keJrjGh6NkM&t=250s (Consulted 14/03/2019)
 IAEA, “Radioactive Waste - The Journey to Disposal”, Vienna, Oct 2014.
URL: https://www.youtube.com/watch?v=3QXSkXHDZgU&t=238s (Consulted 14/03/2019)
 A. Wade, IRENA and IEA PVPS (2016) - End-of-Life Management: Solar Photovoltaic Panels. 2016.
 R. L. R. Murray, Nuclear energy: an introduction to the concepts, systems, and applications of nuclear processes.
Boston: Butterworth-Heinemann, 2009.
 T. Tsoutsos, N. rantzeskaki, and V. Gekas, “Environmental impacts from the solar energy technologies,”
Energy Policy, vol. 33, 2005.
 Varun, I. Bhat, and R. Prakash, “LCA of renewable energy for electricity generation systems—A review,”
Renewable and Sustainable Energy Reviews, vol. 13, no. 5, pp. 1067–1073, 2009.