Consequences” by Donald N. Dewees, Ontario Hydro at the Millennium
ISBN 0-7735-1426-0&9, McGill - Queen’s University Press, Montreal, 1996, pp
Professor Dewees has initiated a broad review of the environmental
consequences of nuclear energy in comparison with coal-fuelled generation. He
has looked at the full range of the fuel cycle from the point where fuel comes
from the ground to decommissioning of plants.
The opening tone, even the title, of Professor Dewees' study faintly suggests
a presumption that nuclear power is unfairly bearing a lesser share of social
and environmental costs than coal-based electricity. However, as he proceeds
through his step-by-step review he finds, in fact, that health and environmental
costs of nuclear generation are probably very low relative to this competitor.
He has found widely varying information on the costs associated with
accidents, largely based on the major difference in estimates of, and actual,
consequences of accidents at the Three Mile Island and Chernobyl reactors. He
concludes that these costs have little effect on the cost of electricity in
Ontario, as design differences between the Chernobyl and CANDU reactors result
in much reduced probability and consequence of major CANDU accidents.
Professor Dewees is less convinced that decommissioning and spent fuel
disposal costs will be as low as current nuclear industry estimates. He points
out that no Canadian reactors have been completely decommissioned. Canada has no
spent fuel disposal facility. He believes that lack of practical experience with
these activities poses a risk that actual costs will turn out to be greater than
estimated. I can add only a little to the comments of Keith Dinnie and Stephen
Allen on these issues.
The environmental assessment of the Canadian spent fuel disposal concept is
getting underway in 1995. Technical and economic issues have been thoroughly
studied. A good measure of practical experience has been gained through the
development of research facilities. A huge amount of information is available to
the public. I repeat, for the reader, Professor Dewees' reference to a
document that provides a window to this information.
I speculate that when this concept is fully evaluated in this public forum that
the nuclear industry may be accused of spending too much money on a simple
Professor Dewees cites lack of experience with decommissioning as a basis for
projections that decommissioning costs will exceed estimates made by the nuclear
industry. I believe the reports he has reviewed do not fully reflect Canadian
experience with decommissioning of reactors and other nuclear facilities. In
addition to the experience with Gentilly 1, cited by Professor Dewees,
decommissioning has commenced at the Douglas Point and NPD reactors in Ontario.
Additional information on these projects, and others, is available from the
In view of this experience base, it seems unlikely cost overruns would be as
great as the factor of 5 considered by Professor Dewees. Even with such a large
cost overrun, Professor Dewees indicates the cost of decommissioning would not
greatly increase the cost of electricity generated by nuclear power stations.
Professor Dewees mentions the potential externality effects from carbon
dioxide emissions, which are expected by many climate experts to lead to global
warming. The information he cites pays scant attention to costs which may be
incurred. Erik Haites raised a concern that proliferation of independent power
producers might make the control of carbon dioxide emissions more difficult. I
would also like to remind participants of this issue and introduce some
illustrations which show the contribution nuclear electricity is making to the
reduction of carbon dioxide emissions in Canada.
Figure 1 provides information on the basic cycle of life on earth. Our
planes, trains, automobiles, and power plants are becoming a significant part of
earth's life based on processing and circulation of carbon containing materials.
The information presented shows that annual carbon dioxide from fossil fuels is
several percent of that estimated to be processed annually by earth's plant
Figure 2 shows the strong correlation between our use of fossil fuels and
levels of carbon dioxide measured in the atmosphere.
Nuclear energy releases no carbon dioxide to the atmosphere during plant
operation. Figure 3 shows the location of 32 CANDU and related reactors
operating throughout the world. Eight more are under construction. Replacement
of high carbon content fossil generation by one large CANDU can reduce Canada's
carbon dioxide generation by as much as 1%.
The solid line of figure 4 shows Canada's total carbon dioxide emissions from
1950 to 1990. The dashed line diverging from the top indicates the extent of
emissions had we not followed the nuclear option for electricity generation and
had chosen the carbon-based fossil fuel option. This indicates Canada's 22
nuclear plants are reducing carbon dioxide about 15% from what might have been.
This is equal to the magnitude of carbon dioxide emission reduction Canada has
proposed in response to international concern with respect to global warming.
In closing I should just like to say I am pleased you are contemplating
changes of regulations required to ensure competitive, efficient, and safe
electricity supply in the 21st century. The need to develop regulations which
realistically reflect all environmental costs is emphasized by several of the
contributors to this volume. Professor Dewees' preliminary assessment indicates
that nuclear energy does not carry with it significant external environmental
costs. Should the costs associated with carbon-dioxide-induced global warming
turn out to be significant, carbon-dioxide-free nuclear energy will flourish.
Energy of Canada, "Summary of the Environmental Impact Statement on the
Concept for Disposal of Canada's Nuclear Fuel Waste," AECL 10721 COG-93-11,
Denault and L. de Pabrita, "Gentilly 1 Nears Static State," Nuclear
Engineering International (August 1985).
Pratapagirl, et al, "Cost Estimate for Decommissioning a CANDU 6 MKI
Nuclear Generating Station," CNA/CNS
Annual Conference, Ottawa, Ontario,June 4-7,1989.
 B. Gupta,
"Progress of Decommissioning Projects in Canada," Nuclear Decom '92:
Decommissioning of Radioactive Facilities, Institute of Mechanical
Engineers, London, February 17-19, 1992.