Among environmental groups, Greenpeace has a reputation for being hostile to technologies like genetically modified foods and nuclear power, as well as of often saying poorly justified and hyperbolic things about them. As a civil servant, I remember learning never to trust figures or claims found only in a Greenpeace report, but to seek corroboration from someone a lot more credible like the Pembina Institute.
A comment in an article from today about premier elect Doug Ford promising to keep the Pickering Nuclear Generating Station open to 2024 provides a case in point:
“If an accident happened at this station, which we don’t want to happen, it would be way worse than Chernobyl or Fukushima,” said Shawn Patrick Stensil, a spokesperson for Greenpeace Canada.
This is nonsense. Chernobyl had a design massively less safe than any western nuclear power station, and as a consequence the release of radioactivity was far greater than from the three nuclear meltdowns in the General Electric boiling water reactors at Fukushima Daiichi. Those meltdowns happened because a tsunami swamped the emergency diesel generators needed to run pumps to cool fuel rods after an emergency shutdown, and because the on-site electrical distribution system was destroyed by the tsunami. Barring an asteroid impact, nothing comparable is possible at Pickering. Even if a colossal disaster caused similar damage to the plant, the situation would not be comparable to the devastation in Sendai after the tsunami and either emergency power to the pumps or emergency cooling water to the reactor cores would prevent any meltdown. Following Fukushima, North American nuclear operators pre-positioned emergency equipment precisely to deal with such a station blackout.
When environmentalists choose to use fear as a motivator, it’s natural to extend it to hyperbole when people aren’t giving you the reaction you want. It’s also easy to unthinkingly buy into frightening claims when they correspond to your existing ideological viewpoint and preferred policy positions. Such emotional reflexes, however, cannot be allowed to drive our public policy choices when deciding how to address climate change. It may be that nuclear power is not a cost-effective climate change solution, or that the Pickering station doesn’t make sense to keep running. Baseless comparisons to the world’s worst nuclear disasters, however, obscure rather than clarify the issue.
If you haven’t read many of the technical details but you want to be able to comment intelligently about the Fukushima Daiichi disaster, I highly recommend this presentation:
The Fukushima Nuclear Reactor Accident: What Happened and What Does It Mean?
BACKUP AND ULTIMATE HEAT SINKS IN CANDU REACTORS FOR PROLONGED SBO ACCIDENTS
In a pressurized heavy water reactor, following loss of the primary coolant, severe core damage would begin with the depletion of the liquid moderator, exposing the top row of internally-voided fuel channels to steam cooling conditions on the inside and outside. The uncovered fuel channels would heat up, deform and disassemble into core debris. Large inventories of water passively reduce the rate of progression of the accident, prolonging the time for complete loss of engineered heat sinks.
The efficacy of available backup and ultimate heat sinks, available in a CANDU 6 reactor, in mitigating the consequences of a prolonged station blackout scenario was analysed using the MAAP4-CANDU code. The analysis indicated that the steam generator secondary side water inventory is the most effective heat sink during the accident. Additional heat sinks such as the primary coolant, moderator, calandria vault water and end shield water are also able to remove decay heat; however, a gradually increasing mismatch between heat generation and heat removal occurs over the course of the postulated event. This mismatch is equivalent to an additional water inventory estimated to be 350,000 kg at the time of calandria vessel failure. In the Enhanced CANDU 6 reactor ∼2,040,000 kg of water in the reserve water tank is available for prolonged emergencies requiring heat sinks.
Nuclear power is safest way to make electricity, according to study
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Making electricity from nuclear power turns out to be far less damaging to human health than making it from coal, oil or even clean-burning natural gas, according to numerous analyses. That’s even more true if the predicted effects of climate change are thrown in.
Compared with nuclear power, coal is responsible for five times as many worker deaths from accidents, 470 times as many deaths due to air pollution among members of the public, and more than 1,000 times as many cases of serious illness, according to a study of the health effects of electricity generation in Europe.
“The costs of fossil fuels come out quite high, while the costs for nuclear generally come out low,” said Anil Markandya, an economist at the University of Bath in England and scientific director of the Basque Centre for Climate Change in Spain, who co-authored the study published in the Lancet in 2007.
Canada’s nuclear regulator overlooked dubious data when renewing Pickering plant’s licence, documents show
Pickering nuclear plant needed to avoid energy blackouts, Ontario minister says | The Star
https://www.thestar.com/politics/provincial/2022/09/29/ontario-eyes-plan-to-keep-pickering-nuclear-station-open-for-another-30-years.html