Nuclear's CO2 cost 'will climb'

By Paul Rincon 
Science reporter, BBC News

Some anticipate a major expansion of nuclear power 

The case for nuclear power as a low carbon energy source to replace fossil
fuels has been challenged in a new report by Australian academics. 

It suggests greenhouse emissions from the mining of uranium - on which
nuclear power relies - are on the rise. 

Availability of high-grade uranium ore is set to decline with time, it
says, making the fuel less environmentally friendly and more costly to

The findings appear in the journal Environmental Science & Technology. 

A significant proportion of greenhouse emissions from nuclear power stem
from the fuel supply stage, which includes uranium mining, milling,
enrichment and fuel manufacturing. 

Others sources of carbon include construction of the plant - including the
manufacturing of steel and concrete materials - and decomissioning. 

The authors based their analysis on historical records, contemporary
financial and technical reports, and analyses of CO2 emissions. 

Experts say it is the first such report to draw together such detailed
information on the environmental costs incurred at this point in the
nuclear energy chain. 

Nuclear impact 
The report is likely to come under close scrutiny at a time when
governments around the world are considering the nuclear option to meet
future energy demands and reduce greenhouse gas emissions. 

Mining companies are likely to have to dig deeper for deposits 

Lead author Gavin Mudd, from Monash University in Australia, told BBC
News: "Yes, we can probably find new uranium deposits, but to me that's
not the real issue. The real issue is: 'what are the environmental and
sustainability costs?' 

New uranium deposits are likely to be deeper underground and therefore
more difficult to extract than at currently exploited sites, said Dr Mudd.

In addition, he said, the average grade of uranium ore - a measure of its
uranium oxide content and a key economic factor in mining - is likely to
fall. Getting uranium from lower-quality deposits involves digging up and
refining more ore. 

Transporting a greater amount of ore will in turn require more
diesel-powered vehicles - a principal source of greenhouse emissions in
uranium mining. 

"The rate at which [the average grade of uranium ore] goes down depends on
demand, technology, exploration and other factors. But, especially if
there is going to be a nuclear resurgence, it will go down and that will
entail a higher CO2 cost," Dr Mudd explained. 

Overall, the report suggests that uranium mining could require more energy
and water in future, releasing greenhouse gases in greater quantities. 

New technology 
Thierry Dujardin, deputy director for science and development at the
Nuclear Energy Agency (NEA), said the analysis made an important
contribution to clarifying the impact of nuclear energy on CO2 emissions.