MIT: Slow growth of nuclear could harm climate efforts

The rate of deployment of new nuclear power plants around the world has been much slower than needed in order to combat climate change, the Massachusetts Institute of Technology (MIT) said in an update of its in-depth study on the future of nuclear power.
K.S.Parthasarathy



WNN
Energy And Environment
MIT: Slow growth of nuclear could harm climate efforts
21 May 2009

The rate of deployment of new nuclear power plants around the world has been much slower than needed in order to combat climate change, the Massachusetts Institute of Technology (MIT) said in an update of its in-depth study on the future of nuclear power.

The 2003 edition of the Future of Nuclear Power report said "that in order to make a serious contribution to alleviating global climate change, the world would need new nuclear plants with a total capacity of at least a terawatt [1000 gigawatts] by 2050."

In its updated study, MIT says, "Since the 2003 report, interest in using electricity for plug-in hybrids and electric cars to replace motor gasoline has increased, thus placing an even greater importance on exploiting the use of carbon-free electricity generating technologies."

It added, "With regard to nuclear power, while there has been some progress since 2003, increased deployment of nuclear power has been slow both in the United States and globally, in relation to the illustrative scenario examined in the 2003 report."

MIT noted, "While the intent to build new plants has been made public in several countries, there are only few firm commitments outside of Asia, in particular China, India, and Korea, to construction projects at this time. Even if all the announced plans for new nuclear power plant construction are realized, the total will be well behind that needed for reaching a thousand gigawatts of new capacity worldwide by 2050."

In its updated study, MIT says that, compared to 2003, "the motivation to make more use of nuclear power is greater, and more rapid progress is needed in enabling the option of nuclear power expansion to play a role in meeting the global warming challenge." It added, "The sober warning is that if more is not done, nuclear power will diminish as a practical and timely option for deployment at a scale that would constitute a material contribution to climate change risk mitigation."

Construction costs up

The latest study noted that, "Since 2003 construction costs for all types of large-scale engineered projects have escalated dramatically. The estimated cost of constructing a nuclear power plant has increased at a rate of 15% per year heading into the current economic downturn. This is based both on the cost of actual builds in Japan and Korea and on the projected cost of new plants planned for in the United States. Capital costs for both coal and natural gas have increased as well, although not by as much. The cost of natural gas and coal that peaked sharply is now receding. Taken together, these escalating costs leave the situation [of relative costs] close to where it was in 2003."

According to MIT's study, the overnight capital cost of constructing a nuclear power plant is $4000 per kilowatt (kW), in 2007 dollars. This compares with a figure of $2000/kW, in 2002 dollars, given in the original 2003 study.

The updated study says that, applying the same cost of capital to nuclear as to coal and gas, nuclear came out at 6.6 c/kWh, coal at 8.3 cents and gas at 7.4 cents, assuming a carbon charge of $25 per tonne of CO2 on the latter.



[The updated study can be downloaded from MIT's website]

Will this development help countries which have difficulties in getting electric power due to the peculiarities of geography?
K.S.Parthasarathy



WNN
New Nuclear
Assembly of Russian floating plant starts
20 May 2009

A ceremony has been held to mark the start of the assembly of the world's first floating nuclear power plant in St Petersburg, Russia. Construction had earlier been transferred from Severodvinsk.


The keel was originally laid for the first floating plant - the Akademik Lomonosov - at the Sevmash shipyard in Severodvinsk in April 2007. However, in 2008, Rosatom said that it was to transfer its construction to the Baltiysky Zavod shipbuilding company in Saint Petersburg because Sevmash was inundated with military contracts.



Click to enlarge
Five floating reactors could go to Gazprom to power oil and
gas extraction in Kola and Yamal, with four more used in
northern Yakutia in connection with mining operations. Seven
or eight units could be produced by 2015. (Click to enlarge)


A contract was signed on 27 February 2009 between Rosatom and the Baltiysky Zavod shipyard for completion of the plant. The contract was valued at almost 10 billion roubles ($315 million). A new keel has now been laid at Saint Petersburg for the first floating plant. As part of the contract, Baltiysky Zavod will receive the incomplete floating plants started by Sevmash.

The first plant will house two 35 MW KLT-40S nuclear reactors, similar to those used in Russia's nuclear powered ice breakers, and two generators, and will be capable of supplying a city of 200,000 people. OKBM will design and supply the reactors, while Kaluga Turbine Plant will supply the turbo-generators.



The Akademik Lomonosov was originally destined for the Archangelsk industrial shipyard, which is near to Severodvinsk in northwestern Russia, but the vessel is now destined for Vilyuchinsk, in the Kamchatka region in Russia's far east.


Baltiysky Zavod is to complete the floating plant in 2011. It should then be ready for transportation by the second quarter of 2012 and is set to be handed over to Energoatom by the end of 2012. Rosatom is planning to construct seven further floating nuclear power plants in addition to the one now under construction, with several remote areas under consideration for their deployment. Gazprom is expected to use a number of the floating units in order to exploit oil and gas fields near the Kola and Yamal Peninsulars.

Speaking at the ceremony, Sergey Obozov, director general of Energoatom, said that construction of a second floating plant may start in the autumn of 2010. He said, "We already have agreement with the authorities of Chukotka to station the plant in Pevek."

Bacteria with a built-in thermometer

Enigmatic features of tiny creatures
Parthasarathy



[ Public release date: 20-May-2009


Contact: Dr. Bastian Dornbach
bastian.dornbach@helmhotz-hzi.de
49-053-161-811-407
Helmholtz Association of German Research Centres
Bacteria with a built-in thermometer
Researchers at the Helmholtz Center demonstrate how bacteria measure temperature and thereby control infection

Researchers in the "Molecular Infection Biology group" at the Helmholtz Centre for Infection Research (HZI) in Braunschweig and the Braunschweig Technical University could now demonstrate for the first time that bacteria of the Yersinia genus possess a unique protein thermometer – the protein RovA - which assists them in the infection process. RovA is a multi-functional sensor: it measures both the temperature of its host as well as the host's metabolic activity and nutrients. If these are suitable for the survival of the bacteria, the RovA protein activates genes for the infection process to begin. These results have now been published in the current online edition of the PLoS Pathogens science magazine.

Yersinia can trigger various different diseases: best well-known is the Yersinia pestis type which caused the Plague in medieval times. This led to the death of around a third of Europe's population. The Yersinia enterocolitica and Yersinia pseudotuberculosis species cause an inflammation of the intestines following food poisoning: the bacteria infect the cells of the intestines, leading to heavy bouts of diarrhoea. The Yersinia bacteria contain invasin as a surface protein to help them penetrate the intestinal cells. The immune cells quickly identify this so-called virulence factor as a danger and launch an immune response. To avoid this, the bacteria quickly lose the invasin soon after entering the body. The germs then adapt their metabolism and feed on the nutrients prepared by the host cells. They also produce substances which kill off the body's defence cells, such as phagocytes. Little was known about how Yersinia is able to regulate these individual stages of infection until now.

Researchers at the HZI, led by Petra Dersch, have now identified how these mechanisms work. The RovA protein plays a key role. The protein reads the temperature for the bacteria. Depending on the environment of the bacteria, this protein either contains the factors required for the infection to begin or else adapts to life within the host. "The functioning of RovA in this way is unique among bacteria," says Petra Dersch.

If inhabiting an environment of around 25°C, the protein RovA ensures that the Yersinia bacteria form invasin as a surface protein. This ensures that the Yersinia can penetrate the intestinal cells immediately upon reaching the 37°C intestine via food. In this warm environment, the RovA alters its form and de-activates the gene for invasin production. Without invasin on their surface, the Yersinia bacteria are invisible to the body's immune system. In its new form, the RovA can now activate other genes in the bacteria to adapt the Yersinia metabolism to that of the host.

Until now, little was known about RovA and the fact that it reacts to temperature. Researchers were presented with a puzzle: "We have long been searching for the mechanisms which regulate RovA activity," says Petra Dersch. "It was therefore all the more surprising to discover that RovA controls various processes by acting as a thermometer and as such is self-regulating". At the end of the process, the RovA is responsible for its own decomposition. If the initial stages of infection prove successful, the Yersinia bacteria no longer need the RovA: in its modified form at 37°C, enzymes in the bacteria can attack and break down the RovA.

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Original article: Herbst K, Bujara M, Heroven AK, Opitz W, Weichert M, et al. 2009 Intrinsic Thermal Sensing Controls Proteolysis of Yersinia Virulence Regulator RovA. PLoS Pathog 5(5): e1000435. doi:10.1371/journal.ppat.1000435