Nick Trevethan, PlanetArk 13 Dec 07;
SINGAPORE - Nuclear power's claim to be the answer to global warming is being questioned by reports suggesting mining and processing of uranium is carbon intensive.
While nuclear power produces only one 50th of the carbon produced by many fossil fuels, its carbon footprint is rising, making wind power and other renewable energies increasingly attractive, according to environmental groups and some official reports.
The nuclear industry has come under fire over safety concerns for decades, but a growing recognition of the threat of climate change has put a renewed focus on the amount of greenhouse gas emissions produced throughout the energy chain.
"Nuclear is a climate change red herring," said Ben Ayliffe, Senior Climate and Energy Campaigner at Greenpeace. "There are safer, more reliable alternatives, like energy efficiency and renewables as part of a super-efficient decentralised energy system."
While the earth's crust still has large resources of uranium -- 600 times more than gold -- much of the highest grade orebodies are already being exploited, forcing miners to develop more technically challenging or lower grade resources.
That means uranium mining requires much more energy.
CARBON COST
One example is Cameco's Cigar Lake project in Saskatchewan, which has been plagued with setbacks caused by floods at the underground mine, which may one day supply over 10 percent of the world's mined uranium.
The problems have forced Cameco to push back the production start to 2011 from 2007, and analysts this week said further delays out to 2012 or 2013 were likely.
"The potential is that nuclear will increase its carbon footprint due to the lower grade ores that remain," Tony Juniper of Friends of the Earth said on the sidelines of a UN climate change conference in Bali.
The carbon cost at Rio Tinto's Ranger uranium mine Australia has also risen. The mine produced 17.7 tonnes of carbon dioxide equivalent per tonne of uranium oxide in 2006, from 13 tonnes in 2005, a Rio Tinto spokeswoman said.
She added that part of the rise was due to bad weather which restricted access to high grade ore, as well as an expansion in capacity, and the company was trying to reduce emissions again.
Uranium output at the mine was 4,748 tonnes last year, resulting in around 84,000 tonnes of carbon dioxide. Rio produced some 28.3 million tonnes of carbon across its business.
Despite these industry figures, Clarence Hardy, secretary of the Australia Nuclear Association and president of the Pacific Nuclear Council, says the environmental groups are wrong in their assumptions and that nuclear power is relatively clean.
"Carbon dioxide emissions from the nuclear cycle are very low. They are not zero, but they are low compared to fossil fuels and they are even low compared to hydro," he said.
URGENT SOLUTIONS
Over the life of a nuclear power plant, carbon emissions are between 10 and 25 grams of C02 per kilowatt, as little as one 100th of that of a coal-fired plant, Hardy added.
"Even wind and solar have higher C02 emissions than the entire nuclear fuel cycle from mining through to waste management," Hardy said, arguing that large volumes of steel and concrete -- both energy-intensive products -- were required for those products.
But UK data paints a different picture.
A UK Parliamentary Office of Science and Technology document on carbon emissions puts nuclear's footprint was around 5 grams of CO2 per kilowatt, similar to the figure for offshore windpower at 5.25 grams and above onshore wind at 4.64 grams.
Scientists at the conference in Bali said the world needed urgent solutions and emissions needed to peak within the next 10 to 15 years.
But building a nuclear reactor typically takes decades.
"Even if we started scaling up nuclear power tomorrow we couldn't do that because it would take longer than that to get a serious impact from new reactors," Juniper said.
"The real answer is more renewable, sustainable energy and greater energy efficiency."
