Environmental costs: In a new study, scientists question the sustainability of nuclear power because of anticipated declines in high-grade uranium ore. Above is Australia's Ranger uranium mill in Kakadu National Park.
Credit: Gavin M. Rudd
SYDNEY: The case for nuclear power as a sustainable alternative energy source is challenged by new evidence that greenhouse gas emissions from uranium mining are increasing.
An Australian report, detailed this week in the journal Environmental Science and Technology argues that the availability of high-grade uranium ore will deplete over time making the fuel more environmentally and economically expensive to extract.
The find adds to existing concerns about nuclear energy, such as the problems of disposing of radioactive spent fuel and whether uranium processing leads to the proliferation of nuclear weapons.
Increasing environmental cost
"Commonly in the mining industry, as higher grade ores are mined, lower grade deposits become economic - but this is at increasing environmental costs such as more energy, water, greenhouse emissions, tailings and waste rock," said lead author Gavin Mudd of Monash University in Melbourne.
The 'grade' of uranium refers to how much of the element is found in the ore, an important economic factor in mining. High-grade uranium is easier to process than low-grade, and less expensive to extract, however as this is used up, the industry must turn to lower grades.
For the study, Mudd and co-author Mark Diesendorf, an environmental scientist at the University of New South Wales in Sydney, reviewed existing data on uranium mining, milling, enrichment and fuel manufacture from across the world. This included historical figures showing when most mining had occurred, contemporary financial and technical reports, and CO2 emissions reports.
The goal of the research was to evaluate the true economic and environmental costs of uranium mining. "We wanted to know what the environmental cost regarding mineral production is in terms of greenhouse emissions, water, and energy, and we found that all of these things do increase over time," said Mudd.
"Important contribution"
He noted that, as the quality of uranium ores decrease, more trucks and other equipment are needed to refine them, which wastes more energy and resources. "This is the first time we've put numbers to this concept, rather than it being an anecdotal idea," said Mudd, "There were real numbers available, so it was time to get those numbers together."
Jim Falk, a professor at the University of Melbourne who specialises in the political, economic and cultural impacts of nuclear technology, said that the study is "an important contribution to the debate over climate change and nuclear power."
"The amount of uranium which can be utilised without creating excessive greenhouse gas emissions – and using excessive water – may be rather more limited than has been suggested," said Falk, who was not one of the study's authors. "The potential role of nuclear power, is likely to be also limited by such considerations."
Nevertheless, Falk noted that while critics argue that nuclear energy industry generates large quantities of CO2 (sometimes calculated to be as much for a nuclear power station as an equivalent gas power station) it still generates much less than a coal-burning power plant.
"Fear campaign"
Not everyone agrees with the outcome of the report, however. Michael Angwin, the executive director of the Australian Uranium Association, an industry trade group based in Melbourne, called uranium depletion a "common myth" that amounts to nothing more than a "fear campaign."
Angwin said that the quantity of available uranium is directly related to exploration, and that as exploration increases, new uranium sources will be uncovered. And according to Angwin, Australian uranium exploration is on the rise – between 2006 and 2007 A$114 million was spent on it. He also noted that as technologies get more sophisticated, efficiency will increase, so that the same amount of uranium ore today will create a larger amount of power in the future.
To bolster these claims, the U.N.'s International Atomic Energy Agency (IAEA) reported in March of this year that known uranium resources recently increased by 17 per cent. But this figure was largely a reassessment due to expanded drilling at existing sites, Mudd said, rather than exploration at new sites.
Mudd agreed that there was a connection between exploration and known reserves, but argued that exploration is getting more difficult in that it requires increasingly deep drilling. The more significant issue is the declining grade of new uranium deposits, he said.
Uranium deposits
What about the new deposits found in Canada, the US, Africa?
What?
Okay, this is a common myth promulgated by people looking for any reason to oppose nuclear power. They didn't look at data about carbon emissions from mines and then say, "Oh, my God, look at all that carbon!" They heard first that nuclear was claimed to be carbon free, then they looked at life cycle carbon costs and found this to be untrue, and then they looked at how much carbon is used in mining etc. Then, based on the original false claim for the carbon free status of nuclear they throw these arguments forth. Can anyone find out what the life cycle cost of a photo voltaic cell is per unit electrical output to see if it is sustainable? How about coal mining with its mountain top removal and vast open pit mines and then transport of billions of tons across continents and oceans? I don't have the figures, but this doesn't seem credible, even going after the low grade ores given the enormous energy output of a vastly lower mass of fuel. Compared to coal, there is more carbon used in mining it than uranium, and then you burn it where the vast share of its carbon cost comes in, by orders of magnitude. Once uranium is mined and processed thats pretty much it. Also this article ignores the fact that Thorium is a viable alternative to Uranium in PWRs, pebble bed reactors and molten salt reactors and it is 3 to 4 times more abundant than uranium in the earth's crust. Was this written by someone employed by the coal industry?
Economic Feasability
Uranium ore only has market value and value follows grade. As long as reactors are a cheaper means to producing electric power, ore has value. Once we produce electricity from desert/solar, solar/voltaic, hydro, wind and wave power to a point where electricity drops in price or nuclear power is too expensive to compete, then the Uranium 'ore' becomes a valueless mineralogical phenomenon again.
Because radioactivity is a human health concern, and there are other means to produce electricity that are safer, we should pursue the safer means, shouldn't we?
Yes, but are they practical?
"There are other means to produce electricity that are safer, we should pursue the safer means, shouldn't we?"
Yes, but your premise is false. Wind and solar are not real alternatives to nuclear because they are not a stable base load. Humans can control when a nuclear reactor will be running (99% of the time, there are some unplanned shut downs). Wind power can be controlled by humans precisely 0% of the time.
Pumped storage is the only cost effective electricity storage mechanism. But that still costs a lot, especially if you want to have the entire grid rely on it. There are some various battery technologies being tossed about, but ultra-scale implementation of them would be expensive.
That said, renewable power can supplement good base load sources. But there are limits of usefulness. 20% penetration seems to be the agreed upon maximum.
Concentrated solar does have some nice potential though, especially for you guys down in Australia (assuming Kangaroos don't poop on the panels and smear them all up whilst jumping over them). It's expensive, but it is actually dependable as a base load source since the heat can be stored and used at night.
wind energy
with wind you can't control it but you wouldn't really need to, sure the wind might blow north one day then the next day it could blow south. you cant control it but you don't need to, the wind mills correct them selfs and still store the energy.
Nothing's safer
Radioactivity in large enough amounts is a human health concern, but this doesn't prevent people from spending large amounts of time in high-flying aircraft. Nuclear energy-related doses to nuclear workers are much lower than increased cosmic ray doses, due to altitude, to airline workers.
Uranium currently is less than three percent as costly as natural gas -- 30 cents per mmBTU versus $11-plus for gas. Safety concerns about the former are not genuine; those expressing them, if they live near reactor sites or mines, don't move away. Some of them live in houses they shouldn't be able to afford.
Paper is actually a glowing endorsement of pro-nuclear claims
The paper opens with "The central thesis of pro-nuclear advocates is the lower carbon intensity of nuclear energy compared to fossil fuels". I don't know if the authors intended this, but Mudd and Deisendorf's paper is actually a glowing endorsement of the pro-nuclear "central thesis". The critical figures for comparing the greenhouse intensity of different energy sources is grams of CO2 per kWh or electricity produced using the fuel source in question (e.g. coal, gas, uranium). The authors stop at grams of CO2 per tonne of U3O8 produced but do not take the next step. However, if you convert the authors figures to CO2 emitted from mining operations per kWh of electricity produced from the mined U3O8 you get figures that range from about 0.2-1.2 gCO2 per kWh (with an absolute upper figure of 6 gCO2 per kWh if you use the author's scenario of all of Olympic Dam's energy usage going to uranium production).
So, what do these figures mean? The relevant figure for coal is about 200-250 gCO2 per kWh. Therefore the CO2 emissions from uranium mining is a tiny fraction of this, as always claimed by pro-nuclear advocates. The other relevant figure for a full-energy chain analysis of the nuclear fuel cycle is somewhere between 4 gCO2 per kWh up to around 10 gCO2 per kWh (with a few authors on this subject claiming up to 60 gCO2 per kWh). Either way, the CO2 emissions from the mining operations detailed in Mudd and Deisendorf's paper, even allowing for increases with low grade ores, fit right into the accepted range of CO2 emissions from nuclear as determine by the many full-energy chain analyses.
Re: Paper is actually a glowing endorsement of pro-nuclear claim
Great analysis. I glanced over the article and assumed the study was probably off the mark, I suppose I shouldn't be surprised that it's simply the media mis-representing the results of the study. I'm sure their bias is anti-nuclear.
Uranium... what will happen...
What will happen in a hundred or so years when we find a real good and proper use for uranium?
In stead of digging it all up, processing it in such a way that we can use it to destruction and depleting the world's useful uranium resources to negligible levels, why not save some for when we have a 'real' need and a 'real' use for it.
We know nuclear power is a waste of good resource and we know that renewable resources can easily be harnessed.
Uranim is no different to fossil fuels in so much as its abundance is similarly finite.
So why the hell use up all of something that we one day may be able to handle properly and that we may (again one day) find forms an inescapably essential part of the future of mankind? In other words, imagine... when faster than light travel becomes possible and it is found that uranium is the perfect, if not only, catalyst required to create amenable conditions... will we have any left... or will we have just consumed all the stuff that we could have then used had our ignorance and greed not gotten the better of us in the 21st century.
We should stop living like there is no tomorrow.
We know nuclear power is a
We know nuclear power is a waste of good resource and we know that renewable resources can easily be harnessed.
Uranim is no different to fossil fuels in so much as its abundance is similarly finite.
So why the hell use up all of something that we one day may be able to handle properly and that we may (again one day) find forms an inescapably essential part of the future of mankind? In other words, imagine... when faster than light travel becomes possible and it is found that uranium is the perfect, if not only, catalyst required to create amenable conditions... will we have any left... or will we have just consumed all the stuff that we could have then used had our ignorance and greed not gotten the better of us in the 21st century.
What if it turns out indium used in solar panels is that catalyst? Besides, the waste we're currently burying is more highly concentrated than the ore originally mined. In a hundred years we'll almost certainlly re-open Yucca mountain and reprocess that waste. Nuclear waste is not "waste" the way CO2 gas is.
Uranium can also be economically extracted from the ocean (one thing all of these studies ignore because it's not been done "commercially" - no surprise, it doesn't make economic sense yet). When it comes down to it the studies that are saying we are running out of uranium all have the motive of either promoting a closed fuel cycle or environmentalists who hate nuclear power.