http://www.nature.com/climate/2008/0810/full/climate.2008.99.html
Nuclear energy: assessing the emissions
*Kurt Kleiner reports on whether nuclear power deserves its reputation
as a low-carbon energy source.
*
For decades nuclear power has been slated as being environmentally
harmful. But with climate change emerging as the world's top
environmental problem, the nuclear industry is now starting to enjoy a
reputation as a green power provider, capable of producing huge amounts
of energy with little or no carbon emissions^1
<http://www.nature.com/climate/2008/0810/full/climate.2008.99.html#B1> .
As a result, the industry is gaining renewed support. In the United
States, both presidential candidates view nuclear power as part of the
future energy mix. The US government isn't alone in its support for an
expansion of nuclear facilities. Japan announced in August that it would
spend $4 billion on green technology, including nuclear plants.
But despite the enthusiasm for nuclear energy's status as a low-carbon
technology, the greenhouse gas emissions of nuclear power are still
being debated. While it's understood that an operating nuclear power
plant has near-zero carbon emissions (the only outputs are heat and
radioactive waste), it's the other steps involved in the provision of
nuclear energy that can increase its carbon footprint. Nuclear plants
have to be constructed, uranium has to be mined, processed and
transported, waste has to be stored, and eventually the plant has to be
decommissioned. All these actions produce carbon emissions.
Critics claim that other technologies would reduce anthropogenic carbon
emissions more drastically, and more cost effectively. "The fact is,
there's no such thing as a carbon-free lunch for any energy source,"
says Jim Riccio, a nuclear policy analyst for Greenpeace in Washington
DC. "You're better off pursuing renewables like wind and solar if you
want to get more bang for your buck." The nuclear industry and many
independent analysts respond that the numbers show otherwise. Even
taking the entire lifecycle of the plant into account nuclear energy
still ranks with other green technologies, like solar panels and wind
turbines, they say.
Life studies
Evaluating the total carbon output of the nuclear industry involves
calculating those emissions and dividing them by the electricity
produced over the entire lifetime of the plant. Benjamin K. Sovacool, a
research fellow at the National University of Singapore, recently
analyzed more than one hundred lifecycle studies of nuclear plants
around the world, his results published in August in /Energy Policy/^2
<http://www.nature.com/climate/2008/0810/full/climate.2008.99.html#B2> .
From the 19 most reliable assessments, Sovacool found that estimates of
total lifecycle carbon emissions ranged from 1.4 grammes of carbon
dioxide equivalent per kilowatt-hour (gCO_2 e/kWh) of electricity
produced up to 288 gCO_2 e/kWh. Sovacool believes the mean of 66 gCO_2
e/kWh to be a reasonable approximation.
"The fact is, there's no such thing as a carbon-free lunch for any
energy source."
Jim Riccio
The large variation in emissions estimated from the collection of
studies arises from the different methodologies used - those on the low
end, says Sovacool, tended to leave parts of the lifecycle out of their
analyses, while those on the high end often made unrealistic assumptions
about the amount of energy used in some parts of the lifecycle. The
largest source of carbon emissions, accounting for 38 per cent of the
average total, is the "frontend" of the fuel cycle, which includes
mining and milling uranium ore, and the relatively energy-intensive
conversion and enrichment process, which boosts the level of uranium-235
in the fuel to useable levels. Construction (12 per cent), operation (17
per cent largely because of backup generators using fossil fuels during
downtime), fuel processing and waste disposal (14 per cent) and
decommissioning (18 per cent) make up the total mean emissions.
According to Sovacool's analysis, nuclear power, at 66 gCO_2 e/kWh
emissions is well below scrubbed coal-fired plants, which emit 960 gCO_2
e/kWh, and natural gas-fired plants, at 443 gCO_2 e/kWh. However,
nuclear emits twice as much carbon as solar photovoltaic, at 32 gCO_2
e/kWh, and six times as much as onshore wind farms, at 10 gCO_2 e/kWh.
"A number in the 60s puts it well below natural gas, oil, coal and even
clean-coal technologies. On the other hand, things like energy
efficiency, and some of the cheaper renewables are a factor of six
better. So for every dollar you spend on nuclear, you could have saved
five or six times as much carbon with efficiency, or wind farms,"
Sovacool says. Add to that the high costs and long lead times for
building a nuclear plant about $3 billion for a 1,000 megawatt plant,
with planning, licensing and construction times of about 10 years and
nuclear power is even less appealing.
http://wiki.answers.com/Q/What_is_the_carbon_footprint_of_nuclear_energy
Natalia
On 24/02/2013 8:29 PM, Ray Harrell wrote:
How about farming? The Pol Pot alternative?
REH
-----Original Message-----
From: [email protected]
[mailto:[email protected]] On Behalf Of michael gurstein
Sent: Sunday, February 24, 2013 9:18 PM
To: 'RE-DESIGNING WORK, INCOME DISTRIBUTION, EDUCATION'
Subject: Re: [Futurework] Washington State nuclear waste leak
Carbon based energy sources?
M
-----Original Message-----
From: [email protected]
[mailto:[email protected]] On Behalf Of D & N
Sent: Monday, February 25, 2013 12:05 AM
To: [email protected]
Subject: Re: [Futurework] Washington State nuclear waste leak
To what?
N.
On 24/02/2013 12:52 PM, michael gurstein wrote:
I'm not sure... depending on how you strike your frame of reference,
nuclear would seem to possibly be the least worst least risk
alternative...
M
-----Original Message-----
From: [email protected]
[mailto:[email protected]] On Behalf Of D & N
Sent: Sunday, February 24, 2013 7:02 PM
To: RE-DESIGNING WORK, INCOME DISTRIBUTION, EDUCATION
Subject: Re: [Futurework] Washington State nuclear waste leak
This has been suggested, from time to time, by those who cannot hazard
a guess as to potential for harm. The real message is--don't create it
at
all.
Natalia
On 24/02/2013 9:45 AM, michael gurstein wrote:
One thing I've always wondered is why no one seems to have suggested
just sending it off into space?
M
-----Original Message-----
From: [email protected]
[mailto:[email protected]] On Behalf Of Keith
Hudson
Sent: Sunday, February 24, 2013 1:43 PM
To: RE-DESIGNING WORK, INCOME DISTRIBUTION, EDUCATION; pete
Subject: Re: [Futurework] Washington State nuclear waste leak
At 09:12 24/02/2013, Pete wrote:
(PV) I disagree, in as much as problems at Hanford do not reflect
anything about the current state of nuclear technology.
Hanford is not a commercial power station, it is a federal research
establishment and part of the weapons infrastructure The closest
Canadian equivalent would be Chalk River, but there is really no
equivalent as we made no attempt to refine isotopes for weapons in
Canada.
(KH) Our equivalent in the UK is Sellafield with scores of waste
tanks (some
leaky) contaning radioactive liquids of long half-life that should
have been sequestered decades ago. One of the reasons why a solution
has not yet been found is the poor quailty of scientists and
engineers attracted to a career in nuclear projects. Whereas, 70
years ago, it took dozens of the world's most brilliant physicists to
construct the nuclear bomb, today, most UK universities (201 out of
203) eschew teaching nuclear engineering because they can't attract
students of any calibre. Our Nuclear Inspectorate has been under
strength.
(PV) But Chalk River was a reasearch institute active during the
early years of exploring nuclear energy, and it also has great
warehouses full of hazardous materials.
We have learned much from the activities in these projects, and no
one today would consider storing nuclear wastes as liquids in tanks,
certainly not from power plants, which shouldn't produce such material.
Canadian heavy water reactors, which I might remind you, can run
quite happily on what is considered the spent fuel of a US light
water reactor, typically run on unenriched uranium, which requires
no exotic processing to prepare, and when spent, in a CANDU reactor,
it is really quite spent, and can be prepared as a solid waste block
encapsulated in glass, and stored underground in the same mines from
which it was extracted, nested in gravel beds in the Canadian
Shield, where there is zero risk of groundwater contamination nor
exposure via earthquakes or whathaveyou.
(KH) I didn't know the above, but the point is taken -- apart from "zero"
risk.
(PV) I don't have any really strong opinions about the adoption of
nuclear energy one way or the other, but most criticisms I hear of
the industry just aren't up to speed with the current state of the
technology. Pointing at 60 year old mistakes as a reason to dismiss
the current technology makes no sense.
(KH) One 60 year-old mistake is that no insurance corp has yet agreed
to cover nuclear reactors. Another fact of the last 60 years is that
no civil engineering firm that has been all too eager to design and
build a reactor has yet agreed to run them and to supply electricity
at the price stated on the tin (that is, the low price that
politicians keep on telling us is the real price) -- or indeed to run
them at all. What's more -- considerably more -- is that the cost of
sequestering radioactive wastes year after year, or rather century
after
century, has never yet been estimated and published.
(Even glassified blocks, buried at very deep level has to be
inspected regularly so that its safety for hundreds of generations of
humans is
assured.) The long and the short of both of the above facts is that
nuclear power has had to be subsidised before, during, and after
construction. We've never been given the true costs of
nuclear-generated
electricity.
Keith
-Pete
On Sun, 24 Feb 2013, Keith Hudson wrote:
It was good to read this because I think it comes just at the right
time to permanently affect new build in the advanced countries. The
news of these leaks comes on top of the realization of universal
shale gas and ought
now to
finally stop the bleatings (and false propaganda) of the wannabe
power
station
constructors (who, be it noted, are not the slightest bit
interested in running them once built).
Keith.
At 21:56 23/02/2013, Natalia wrote:
Most of you have probably read this by now. Given what this news
reveals, how can more new builds of such plants be justified?
http://www.cbsnews.com/8301-201_162-57570857/wash-state-governor-6-u
n
d
erground-nuclear-tanks-leaking/
Natalia
_______________________________________________
Futurework mailing list
[email protected]
https://lists.uwaterloo.ca/mailman/listinfo/futurework
_______________________________________________
Futurework mailing list
[email protected]
https://lists.uwaterloo.ca/mailman/listinfo/futurework
_______________________________________________
Futurework mailing list
[email protected]
https://lists.uwaterloo.ca/mailman/listinfo/futurework
_______________________________________________
Futurework mailing list
[email protected]
https://lists.uwaterloo.ca/mailman/listinfo/futurework
_______________________________________________
Futurework mailing list
[email protected]
https://lists.uwaterloo.ca/mailman/listinfo/futurework
_______________________________________________
Futurework mailing list
[email protected]
https://lists.uwaterloo.ca/mailman/listinfo/futurework
_______________________________________________
Futurework mailing list
[email protected]
https://lists.uwaterloo.ca/mailman/listinfo/futurework
_______________________________________________
Futurework mailing list
[email protected]
https://lists.uwaterloo.ca/mailman/listinfo/futurework
_______________________________________________
Futurework mailing list
[email protected]
https://lists.uwaterloo.ca/mailman/listinfo/futurework
_______________________________________________
Futurework mailing list
[email protected]
https://lists.uwaterloo.ca/mailman/listinfo/futurework
_______________________________________________
Futurework mailing list
[email protected]
https://lists.uwaterloo.ca/mailman/listinfo/futurework
