In two of my recent posts:
1.Renewable and Alternative Energy Sources Ranked_Review of solutions to global warming, air pollution, energy security_Information Overload Mastered, (09 March 08).
2.Solutions to global warming, air pollution, and energy security reviewed _Parametres used to classify and rank_Follows previous post (21Feb 09).
I introduced readers to Mark Z. Jacobson's strong pitch, in his "Review of solutions to global warming, air pollution, and energy security", in favour of "renewable energy sources" his 1st and 2nd choices, termed, Tiers 1 and 2. followed by his less favoured 3rd choices, Tier 3, which includes alternatives energies; coal-fired power with the "elusive" carbon capture and sequestration (Coal-CCS) , and the experienced and successful Nuclear route. Both coal without CCS and Nuclear are current main and acknowledged alternative power supplier respectively. By the same, both are major users of high-temperature corrosion resistant alloys and as a very early retired specialist in the later fields, I -and colleagues- shall come back, with some delight, to talk about what the metallurgists, materials scientists and engineers can hope to bring to humanity's energy-climate plight which is unlikely to miraculously disappear.
At present, it is the latter 3rd choice, tier 3, in particular Nuclear, which will be considered here thanks to Benjamin K. Sovacool, a research fellow at the National University of Singapore, who recently analyzed more than one hundred life-cycle studies of nuclear plants around the world, his results published in August in Energy Policy (ref1.).
The life-cycle-assessment (LCA) evaluates 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.
The Good News:
From the 19 most reliable assessments, Sovacool found that estimates of total life-cycle carbon emissions ranged from 1.4 grammes of carbon dioxide equivalent per kilowatt-hour (gCO2e/kWh) of electricity produced up to 288 gCO2e/kWh.
Sovacool believes the mean of 66 gCO2e/kWh to be a reasonable approximation.
and according to his analysis,
-nuclear power, at 66 gCO2e/kWh emissions is well below
-scrubbed coal-fired plants, which emit 960 gCO2e/kWh, and
-natural gas-fired plants, at 443 gCO2e/kWh.
However, nuclear emits twice as much carbon as solar photovoltaic, at 32 gCO2e/kWh, and six times as much as onshore wind farms, at 10 gCO2e/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.
The Bad News-Work To Be Done (TBD)?
Over and above the already extensive ranking of the nuclear route there remains many serious concerns about the risks caused by uranium mining (eg radon gas levels on miners), and waste disposal both from the mining operations on miners and locally exposed populations-cradle side or to local populations on the end waste "grave side" if I may use the expression. A rapid Google Search turns-up an impressive list of concerns. however at the time of this post, again a scientific pointer is given by BK Sovacool in his paper on bird mortality or rather avian mortality (birds, bats...etc) (Ref. 2 below) which surprisingly ranks wind the least harmful to avian species followed by nuclear and worse of all coal power generation. (personal communication by Mark Z. Jacobson.)
NB. in both references there is strictly no reference to "Superman or woman! " This is perhaps a lesson in it's self!
References:
1."Valuing the greenhouse gas emissions from nuclear power: A critical survey" [pdf].
2. Contextualizing avian mortality: A preliminary appraisal of bird and bat fatalities from wind, fossil-fuel, and nuclear electricity [abstract]
A newly developed website has made understanding science, its processes, it's interactions and it's wide reach, a relatively simple, very attractive and enjoyable task. Although the site has been designed by teachers and lectures for teachers and includes elementary teaching resources, I firmly believe that the site will prove highly significant in clarifying the scientific method not as a linear process but as a system of interactions. It is, not only, a timely reminder and support for all professional in the science industry: a must for all scientists technologists, engineers including science communicators, be they scientists or laymen, but also to the general public, intrigued often worried by the influence of the scientific industry, its technology and engineering on their daily lives.
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