Monthly Archives: May 2018

TESLA UK: Some remarks on the use of batteries in the network.

1) The Tesla project in the United Kingdom is apparently identical in size to the one that Tesla put into service at the end of 2017 in South Australia to stabilize the network. It is mainly used for primary adjustment and works very well because of the rapid response of the batteries. Beyond reasons of network security, the interest of these batteries can also be economic if they make it possible to substitute for the primary adjustment provided by controllable means which, therefore, can operate in base at 100% of their power (and not 95%) to improve their production and profitability. It’s a question of comparative costs,

2) That being said, it is essentially the power that is interesting in this case, hence the type of design 100 MW but only 129 MWh capacity, which allows only to spend very short spikes, less than 1 hour (because the batteries can not be completely discharged),

3) To pass for example the winter tip of 19 h in France, which has a roughly triangular evolution shape amplitude of about 5 GW (or a little more) and whose base has a duration of about 2h30 it would effectively have a useful storage capacity of 6 to 7 GWh. Available capacity with current PSP, but which would be much more expensive with batteries. That being said, occasionally replacing some peak TACs of 400 MW by a few batteries of the same power capable of storing 1 to 2 hours of energy can probably provide a partial solution which could be interesting to quantify comparative profitability, knowing that also avoids CO2 emissions. But this does not make sense as long as the current PSP and TACs are sufficient.


TESLA batteries in Australia: storage or anti-blackout?

Translation :

788 x16 Powerwall batteries at 5000 USD, or about 63 MUSD, just in batteries + infrastructure and cooling.

Nearly 100 MUSD!

The price is obviously interesting, but it is difficult to deduce in this case a return on storage, or what amounts to the same cost of MWh destocked. Indeed, the role of this battery (126 MWh of storage for 100 MW of power) is not primarily the storage of energy (the theoretical duration of destocking is 1.26 hours, in practice about 1 hour maximum) knowing that a battery is not used until its complete discharge to preserve its longevity, which limits its possibilities of smoothing the demand or the variations of the EnRis).

The main purpose of this battery is to stabilize the frequency of the network by capping the very rapid fluctuations of EnRis, a battery being able to absorb or restore energy to the network in extremely short times. Its role is therefore to achieve a primary ultra-fast power-frequency setting which makes it possible to correct the gaps before they have consequences on the rest of the network (for lovers of regulation theory, the constants of action time batteries are much lower than network reaction time constants). This system works well, it has been extensively tested by EDF R & D on a test loop of about ten MW and is used with success apparently in several (small) isolated networks of the islands, with powers of the same order.

Functionally, the batteries thus undergo loads / discharges at a high and random rate, according to the cumulative fluctuations of consumption + EnRis. Economically, it is not the stored values that are the main interest, but the stabilization service rendered to the network, which can be extremely large amounts if it avoids blackouts as experienced in the network. South Australian between autumn 2016 and winter 2017 (spring and summer periods for Australia). To fix the ideas, the cost for the community of a blackout in France is estimated by RTE to 25 000 Euros / MWh undistributed !!! I do not know what it is for the South-Australian network, of a very different scale (3 GW of installed power approximately, including imports) but this cost being proportional to the standard of living of the country (it corresponds essentially to the loss of GDP due to the general lack of electricity), it should logically be of a comparable order of magnitude per MWh not distributed.

It remains to be verified that the 100 MW of batteries will be sufficient to stabilize a network whose maximum power can reach 3 GW in order of magnitude. Answer by the facts in a few months, but we can think that the managers of this network have made good simulations … It is to wish for them and for … Elon Musk !

One of the constraints of the batteries concerns the permissible discharge current, just like the charging current.

So the amount of energy stored is interesting data and, in this case, 126 MWh is a high value. However to see the ability to maintain the network frequency during sudden changes, it would be good to know the maximum intensity of discharge.

To get an idea, we can compare the capacity of the battery (126 MWh) and power that allows itself to be drawn (100 MW) to those of the battery (the same type – Li-ion) which is mounted on a Tesla Model X P100D, ie 100 kWh resp. 568 kW.

On the car, it is authorized to pump power proportionally much larger, because this power is absorbed during acceleration, necessarily short, much shorter than the periods during which the battery will be 126 MWh solicited at the level of 100 MW.

The ashes of Superphenix


After its best year of operation, Superphénix was finally closed in 1996, because of an electoral agreement with the Greens and legal disputes, particularly with the canton of Geneva in which these same greens were already involved.
Would this technology have been sold to Russia, as well as some of the sodium stocks, as some sources claim?

In any case, the Russian Rosatom has just been awarded the “Power Award2016” of the best nuclear power plant in the world for its BN 800 whose commercial exploitation has just started this November 1, 2016.

This breeder is thus reborn from the ashes of the fourth generation technology, fast neutrons with sodium cooling, abandoned just 20 years ago by France with the closure of Superphénix. This suggests thousands of years of available fuel and a big step forward in the treatment of waste.

This prize, awarded by the US press in Rosatom, concretizes the “spectacular breakthrough” of Russia since 2005, which made it the world leader in nuclear energy.

Russia has at the same time a basement full of oil, whose production has just exceeded that of Saudi Arabia. It is also the second largest producer of gas, while Europe, heavily dependent on it, remains at the mercy of diplomatic tensions, so all the more worrying that Russia has an alternative to the east. .

In France, the Atomic Energy Commission is working on the design of the equivalent of the Russian BN 800, the experimental reactor ASTRID (Advanced Sodium Technological Reactor for Industrial Demonstration) which could see the light at the earliest in 2025, after 30 years of interruption of the sector.

The hard awakening of France on its faded laurels

For having considered that its nuclear fleet represented a rent for life and required only a minimum of maintenance and a total absence of renewal, France is now faced with the obligation to bring several reactors into conformity.

And suddenly seems to realize that its 11000 MW wind supply electricity only in the wind and not the needs of consumption.

Risking thus to understand, at his own expense, that in the absence of this wind, it is the TOTALITY of the PILOTABLE power currently installed that the country needs.

Indeed, a supply disruption, in the event of a period of high anticyclonic cold (by definition, without wind), would have dramatic repercussions.

But at least it would highlight the little sense of the concept of competitiveness released from the comparison of a random MWh with a controllable MWh.

The services rendered by each of them being out of proportion.

The return to reality

According to a confidential report, consulted by The Guardian, the European Commission intends to reconsider the advantages granted to renewable energies, in order to allow more flexibility of production and more competitiveness.
If the Russians have oil, they seem to have more in the minds and remained unaffected by the mirror larks wind, if we believe their only 17 MW wind turbines installed since 2007, listed on the Windpower website.
Our lag in energy is certainly not the one we believe.

Nuclear Fusion: “Why I think Lockheed Martin “… will not succeed, and some other considerations

2015 : translation.

Reaction to ads of this type in the media:

Fundrising …
The art of passing messages of hope to reach research funds …

The media loves it …
An announcement, a denial, two informations to publish…
No ethical will to confront points of view and make sense.
And it does not matter if the discernment of the public is affected …

Criticize this ? You go for joy flaps that brandish an irresponsible “it will never work!”

Example of a reasoned answer:

“When we go to the Lookheed site, not a single paper published, for example on the magnetic containment envisaged, which seems to be the only originality. Without revealing all the secrets, it would be normal to have access to results. the description of the technology, it is said, about neutrons produced during the tritium + deuterium fusion reaction “:” These neutrons heat the reactor wall, which can be used to drive turbine generators, as if the thing was self-evident. But 14 MeV neutrons are not content with “heat the reactor wall”, they trigger nuclear reactions that degrade the properties of the wall, to the point that a special machine must be built to study this single issue, IFMIF. This must be preceded by a preparatory machine IFMIF / EVEDA, product of a France-Japan cooperation, in progress.

The design of the magnetic field of ITER is perhaps not optimal, other geometries are studied in machines called Stellarator (in particular in Germany). But as long as Lookheed does not say anything about materials, energy recovery and generated helium, we are still far from the prospect of a reactor – if only an experimental one.

The physicists of this community have the unfortunate tendency to make journalists believe – which they gladly report – that once the behavior of plasma is controlled, we have a reactor. It’s powder in the eyes ”

And these examples of ads are regular …

09/25/2015 6:00 PM
Small-scale nuclear fusion may be a new energy source | EurekAlert! Science News –…

#FundRisingStrategy If I was an oil industry, I would not like to invest in fission because fusion will arrive soon ..

Or probably:

News> Nuclear fusion: an aneutronic reactor as an alternative to Iter?

Sweden’s Low Carbon Strategy

Translation of : La stratégie bas carbone de la Suède by Jean Fluchère

France always puts Germany forward as a model but Germany’s “Energiewende” is an obvious failure as even France Stratégie recognizes.

On the contrary, we have a remarkably successful low carbon strategy example with Sweden and its 10 million residents.

As early as 1991, Sweden embarked upon what we now call a low carbon strategy.

Between 1990 and 2013, this country, which was already one of the lowest per capita carbon dioxide emitters among OECD countries, succeeded in reducing its emissions by 22%.

France, which has committed to reducing its carbon dioxide emissions by 40% between 1990 and 2030 and by 75% between 1990 and 2050 must take an interest in Sweden’s energy policy.

In the first place, the stability of the electricity demand since 1987, in spite of a population increase and a wider use of electricity for heating, finds an explanation with the government’s decision, following the oil crises of the 1970-1980 decade, to launch the construction of one million dwellings with reinforced thermal insulation, which means that more than 10% of the existing housing was renewed. The approach was rational, starting with the replacement of the most energy intensive buildings and the energy saving renovation of the others.

Situating Sweden from the energy point of view, we note that it has a large hydraulic and biomass energy potential, including its wood fuel. Forests cover 54% of the country and account for 19% of the EU’s forest area. Sweden is the second largest worldwide exporter of paper, paper pulp and wood (second to Canada). Moreover, the wood industry produces multiple wastes that can be recycled into the energy sector.

Sweden has halved its oil consumption within 40 years: 16.0 Mtoe petroleum products consumed in 2011 compared to 31.3 Mtoe in 1970, before the oil crises.

It has decided to retain its nuclear power, up to a 10 GW maximum capacity.

Its population is highly urbanized, facilitating the use of thermal renewable energies in district heating networks.

Thanks to its well structured energy policy, Sweden has succeeded in having no more than 30% fossil fuels in its final energy consumption in 2013 (compared to 65% in France) and it has increased its GDP by 60 % between 1990 and 2013 while reducing its CO2 emission by 22%.

Sweden’s low carbon strategy rests on 4 fundamental pillars.

1. Carbon-free electricity generation.

The generation of electricity is based on a hydropower and nuclear power mix which ensures 85% of the production. The rest is produced from biomass for 6%, wind power for 7% and fossils for 3%, as a backup to deal with the large weather fluctuations of the country. Note that nuclear power is operated in base load mode. The fluctuations of wind power are compensated via hydropower dams.

Regarding nuclear power, in a referendum organized in 1978, Sweden had approved a nuclear power phase-out scheduled over 30 years but this decision was reversed in 2009 when it was decided to keep a nuclear power fleet limited to a 10 GW maximum capacity, with an option to increase the capacity of individual plants (which was done). The replacement of an existing plant with a more efficient plant is allowed, provided the existing plant is permanently shut down. Only as a plant reaches end of life and is permanently shut down will a new power plant be allowed to be brought into operation.

Recently, the Swedish government has decided to allow Ringhals 1 and 2, which were brought into operation in 1975 and 1976, to continue operation up to 50 years, and up to 60 years for Ringhals 3 and 4 along with Forsmark 1 to 3, under provision of an upgrade to the highest safety level.

Note that 4 of the 7 plants are boiling water reactors (BWR), the same type as the Fukushima plants but, contrary to the Fukushima plants, the upgrades applied to pressurized water reactors have been adapted to these.

Thanks to this carbon-free electricity, Sweden has been able to realize use transfers and reduce its fossil fuel consumption.

2. Considerable use transfers

Sweden has specifically targeted the replacement of fossil fuels. The Swedish industry, which still accounts for nearly 50% of the country’s GNP, relies mainly on carbon-free electricity and on thermal renewables for heat, the two representing 78% of the energy consumption in the sector.

The residential and tertiary sectors rely on thermal renewables and electricity for up to 91% of their heating needs. Oil and especially natural gas have been considerably reduced, thanks to a deep transformation of the heating systems which use standard electricity, heat pumps (the Swedes have acquired close to 100 000 heat pumps per year for a good number of years (both ground-source and air-source heat pumps)) and cogeneration with biomass-burning district heating.

This results in the Swedes being the largest electricity consumers in the EU with almost 14MWh per capita, compared to the 7MWh per capita of France. On the other hand, the fossil fuel consumption is much smaller.

3. A consistent energy policy

Above all, Sweden defined an energy efficient policy, with the construction of well insulated housing and an energy-saving upgrade of existing buildings.

The development of carbon-free technologies rests on a well adapted fiscal policy and on efficient financing measures.

The Swedish government aims to reduce CO2 emissions by 40% by 2020 and 100% by 2050.

It has not adopted the EU emissions trading system which, by general agreement, is not operational with a CO2 price of 7 €/tonne. But, as early as 1991, it has established a progressive taxation of the tonne of CO2 which is currently taxed at over 120 €/tonne. This tax applies primarily to private individuals so as to avoid jeopardizing the industry relative to international competition.

This carbon tax is complemented with a tax on energy, excluding electricity.

As a counterpart, the income relative to these taxes enables cost deductions for companies and to support energy saving with grants at the national and local scale.

4. Transportation

The transportation sector remains the largest GHG emitter in Sweden (it is number 2 in France). It absorbs nearly 80% of the final consumption of petroleum products.

The Swedish Energy Agency now considers low carbon transportation its priority research field. Henceforth, success in reaching the 100% CO2 emissions reduction in 2050 depends on this sector.

The Norwegian neighbor’s example, with highly developed electric powered mobility, will very probably be taken on in Sweden.


Let us not pick the wrong model. Germany’s energy transition is a failure.

Whereas Sweden’s energy transition is a remarkable success.

Book : Underexposed ! – And if the radiation was good for you ?

In english.

“The synthesis in French of the book Under-Exposed of American Ed Hiserodt proposed by Michel Gay is at least a provocative book, and as such, disturbing. The impression is mixed: while being convincing on the merits, the author sins with some excesses that could discredit him and return back to back with those he denounces and criticizes.

And yet, let’s take the risk of getting behind him. What is this theory that he denounces, what is the message he asserts? It attacks this relentlessness, based on a complex historical construction, to perpetuate a “non-scientific theory”, the “linear relationship without threshold” (RLSS), which extrapolates to low doses of irradiation the deleterious effects noted in higher doses in terms of radiation-induced carcinogenesis … However, if the RLSS was invented for the purposes of radiation protection, allowing the establishment of a very “precautious” protection (which is already questionable in terms of profit / risk), it is absolutely irrational from a scientific point of view, because it is not supported by anything and leads to nonsense, as the calculation of the number of victims of low doses … that we never see!

Unfortunately, its dogmatic character and validated by the “Authority” with a large A (we must rather say the Authorities), feeds fears related to radiophobia, and the psychological and societal consequences are numerous and not harmless. However, for low doses (in practice, less than 100 mSv whole body, which for the novice reader can be translated as “below forty times the irradiation received in a year”), the best epidemiological studies have not never been able to highlight the over-incidence of cancers or leukemias due to radiation, and modern radiobiology brings more and more arguments, scientific this time, to demonstrate the harmlessness, even under certain circumstances, the protective effect1 of low doses. of radiation – starting with radiation of natural origin, which is rather reassuring! It is therefore necessary to at least criticize, and perhaps denounce, the unfounded excesses that lead to high and unjustified expenses, irrational choices and the maintenance of fears that have no place to be, based solely on this misunderstanding. the RLSS.

This is what Michel Gay denounces, and he does it loud and clear, a little in the hussar and with a Rabelaisian side that is not unpleasant, but, some would say, excessive … Yes, but it is to fight against such a societal and ideological force of denigration and misinformation affecting crucial areas such as health, energy policy, that we must forgive this excess, in the name of David against Goliath.

Excessive, it is even more so, when he takes the banner of hormesis, to extol the beneficial effects of low-dose radiation. Which is not so extravagant, let’s repeat it. Very serious studies are quickly accumulating2 that go in this direction, and it is also logical that our organisms have always been exposed to radiation of natural origin (cosmic, telluric, foodborne and even indoors). of our own cells) have adapted to it; a selective advantage could even be linked to this phenomenon by maintaining active cells in the mechanisms of elimination of free radicals of all origins (starting with aerobic respiration using dioxygen). From there to claim our dose of daily rays, otherwise we would be in danger, there is a big step that Michel Gay probably passes with too much joy. Especially in his passion, he is carried away to the point of making small mistakes of little importance, as when he speaks of the surgical treatment of malignant lymphoma, for example (we do not operate this disease). But that does not put his argument back on the merits.


And so, in conclusion, a militant book, partisan, which targets just but more in the manner of songwriters and cartoonists with a scientific approach. It deserves to be read to hear the militant and denunciatory speech, it deserves to be criticized for its excessive and polemical sides, so read it but do not take it for cash, it should be read with caution, spirit criticism, and put it on the record of the delicate question of low doses of irradiation. Like any pavement thrown into a pond, it splashes. But, overall and in the end, once the excesses are rejected, its main message is a good message: we must finish with the RLSS.”

To know more :

Radioactivity: Are you ALARA or ALAIN (As Low As In Nature) ?

Automatic translation

If the ALAIN principle were adopted, humanity could do without fossil fuels more cheaply and without compromising its security.

By Bruno Comby and Michel Gay.

While in France, coal and gas have been almost entirely abandoned in favor of nuclear power, the United States continues to burn huge quantities for their electricity production, which “is not good for the planet “.

As the most powerful international player, the United States should promote the development of nuclear power in the world to avoid burning fossil fuels. The latter would be more useful elsewhere, for example in the production of steel, fertilizers, plastics, or drugs.

What the IPRC should do
To do this, the International Committee for Radiological Protection (ICRP) should be asked to:

1) to remove the ill-founded and unscientific assumption of the so-called Linear No-Threshold (LLSS) rule, also known as Linear No Treshold (LNT),

2) recognize the beneficial effects on health of low doses of radioactivity (hormesis effect), which benefit the spa guests in most spas,

3) modify the current principle of radiation protection ALARA (“As Low As Reasonnably Achievable” radiation standard as low as reasonably possible) in order to transform it into ALAIN (“As Low As In Nature”, radiation as low as in nature), because the earth is naturally radioactive.

This ALAIN principle is theoretically essential for laying the foundation for radiation protection in the future. It was first articulated and defined in 1994 by Bruno Comby in his book Un ecologiste pour le nucléaire (Editions La Compagnie du Livre, 1995).

The ALARA principle

The principle ALARA leads to a cost as high as possible to make the nuclear unacceptable (consequence of the increase of the expensive protection rules to respect the reduction of the authorized doses). Radiation protection based on this principle hinders the development of nuclear power, and in some cases eliminates it, making progressively uncompetitive the cleanest of all energies.

If the ALAIN principle were adopted, humanity could do without fossil fuels more cheaply and without compromising its security.

The United States should understand that working with Europe to do without fossil fuels through nuclear energy, the only viable and affordable alternative, is important for global security and the survival of our democracies.

They should actively help the world revive nuclear energy by supporting the development of the new generation of GEN III reactors, and by opening the way to the fourth generation (GEN IV) with ‘regenerative’ reactors, or even ‘ breeder reactors “, with uranium, then with thorium.

A geopolitical choice

If the United States does not do this work in cooperation with Western Europe, the two continents will lose their global supremacy in this area. And it will probably be China and Russia, and perhaps even India, which after 2030 will be masters of global nuclear power generation.

Abandoning the ALARA principle and turning to ALAIN would be a healthy first step to start massively replacing fossil fuels with nuclear power.

The ALAIN principle better protects the health of the public than the ALARA concept because it applies to both natural and medical and artificial radioactivity. The ALAIN principle encompasses them, while the ALARA principle applies only to artificial radioactivity (industrial, and sometimes medical, but separately) by tolerating other sources of radioactivity. “ALARA” neglects the much higher natural radioactivity, which has potentially much more health effects (negative, null, or positive).

All sources of exposure to radioactivity

Natural radioactivity accounts for 90-99% of the doses to which most nuclear workers are exposed and 99.9% of the doses to which the public is exposed.

Taking into account (with ALAIN) ALL sources of exposure to radioactivity is necessary to better protect the health of exposed people, be they the public or the nuclear workers. And, conversely, if necessary, to enable them to benefit from the protective and beneficial effects of hormesis.

This is why the recent ALAIN principle aims to replace the old ALARA concept, partial, ill-founded, insufficient, and defined in the 1970s. But badly founded scientific dogmas (like ALARA) are sometimes long to evolve towards more open, more modern principles, better reflecting scientific reality (such as ALAIN). The logic will certainly end up making its way (see the story of Galileo, or the principle of universal attraction of Newton).

Beyond the future of the nuclear industry, it is public health and the health of nuclear workers that is at stake. It is therefore essential to broaden the basics of radiation protection to ALL radioactivity.

Setting strict standards, as is currently the case, on only 0.1 to 10% of industrial radioactivity and neglecting the remaining 90 to 99.9% of natural radioactivity is absurd and insufficient.

Moreover, the extremism that results from the very definition of ALARA (with no acceptable threshold, thus tending to zero for artificial radioactivity) leads not only to a growing regulatory pressure mortal for the industry, but also to a scientific stalemate by refusing to take into account the hormesis effect. The latter is compatible with the ALAIN principle.

So, are you ALARA (“As Low as Reasonably Achievable”), or ALAIN (“As Low As in Nature”)?

Thorium, an energy miracle ?

Thorium fuel is an interesting option for the future. Has it been abandoned a little too fast?

Thorium By: Science Activism-CC BY 2.0
Today, in the world, uranium is the fuel of all nuclear power reactors1. Technically, another element would be possible: thorium.

Regularly, articles and television shows2 present thorium with advantages superior to those of uranium. Almost a panacea … Thorium would be notably more abundant than uranium, produce less waste and prevent nuclear proliferation.

Thorium: have we really ruined this miraculous way for nuclear?
Let’s compare the two “ways”.

The current path of uranium
The term “uranium” (U) covers a family of uranium (U232, U233, U235, U238) with different atomic nuclei. They are called “isotopes”.

In a schematic way, everything starts with the fission of uranium 235 (U235) which is the only “fissile” isotope existing in nature. It allows to start a nuclear reaction that provides energy. At the same time, it partially transforms uranium 238 (U238), present in the reactor, into plutonium (Pu239), which is fissile. The U238 is called “fertile” because it does not break directly to give energy.

This Pu239 created (it does not exist in nature) fission therefore in turn, gives energy and also transforms the U238 Pu239, and so on ….

This is the “uranium cycle” (U238 / Pu239). This uranium cycle is exploited in all current reactors3 under various modalities.

Of these, only breeder reactors produce as much, or more, of fissile material (Pu239) than they consume. This “regeneration” would consume all natural uranium (U235 and especially U238) to produce electricity and heat for thousands of years for the industrialized world.

However, U235 is relatively rare because it represents only 0.7% of the uranium ore (the rest is precisely U238). At the rate of consumption of current reactors, the technically and economically accessible reserves in the earth’s crust are estimated at less than 200 years.

Hence the interest to get rid of it and to build fast breeder reactors that would use all available natural uranium, instead of less than 1% today. They would multiply by 100 the duration of the usable reserves.

France has enrichment plants for natural uranium. The reserves of U238 stored “off the shelf” (there is no need to extract it from a mine) already correspond to about 3000 years of current electricity generation based on breeder reactors.

The thorium way.
Thorium 232 (Th232) exists only in this form in nature. It is not “fissile” but only “fertile” (just like the U238). We can not extract energy directly by fission. It must first be transformed into U233 which is fissile. This is the “thorium cycle” (Th232 / U233).

But it takes a fissile “match” to create U233 from Th232, just like creating Pu239 from U238. This may be U235 (present in nature) or Pu239 (produced in current nuclear reactors). These last two elements will no longer be needed when a sufficiently large quantity of U233 has been manufactured.

There can therefore be no “autonomous” thorium cycle (based on Th232 and U233) without relying first on the uranium cycle, and especially on PU239 since U235 is relatively rare.

Then, as U233 is produced, reactors operating on the uranium cycle could disappear. However, this “transitional” period should last at least a hundred years4. We must accept to live first with the uranium cycle before going exclusively to the thorium cycle!

The use of the immense natural resource of Th232 also implies the acceptance of the breeder technology (like PHENIX which, in France, worked for nearly 40 years).

It should be noted that the safety standard for the use of the uranium cycle in current reactors (fast breeder reactors or not), as well as that of fuel fabrication and recycling plants, has the enormous advantage of existing. Its development has required decades of global thinking to establish internationally applicable standards and procedures.

However, currently the safety standards for reactors and thorium cycle reprocessing plants that will be technically different (especially because they use a technology of melted salts at high temperature) simply do not exist.

The fission products that dominate the radiotoxicity and heat emission of nuclear waste for several hundred years are equivalent for thorium and uranium cycles with identical electrical production.

Only the radiotoxicity of certain other wastes (the actinides) will be reduced in the thorium cycle if the reprocessing (which remains to be invented) reaches the current performances of the uranium cycle. But this gain will concern “big” elements that will remain underground long after their radiotoxicity is gone. They have a very low mobility in geological environments for which the underground geological disposal CIGEO is currently defined in France (located 500 meters deep).

On the other hand, manipulations of the thorium fuel leaving the reactors will be made difficult5 for the nuclear workers by the presence of U232 highly “radioactive gamma”.

According to some journalists6, uranium would have been privileged at the outset of the industrial development of civilian nuclear power – that which is used to produce electricity or radioisotopes for medicine – mainly because it would also allow the realization of atomic bombs.

This assertion is partially false7, especially for pressurized water reactors (PWR8), the majority (60%) in the world9. No atomic bombs have ever been made from materials extracted from PWR reactors because they produce a “poor quality” plutonium that is inadequate to make a bomb. For a military purpose, the simple technique of separating U235 using centrifuges is much more efficient and does not require any nuclear reactor.

It is a delusion to believe that the nuclear potential of nuclear power would be eliminated because U235 and Pu239 would no longer be used. Indeed, a bomb containing U233 was tested in Nevada in 1955.

So, uranium or thorium?
Electricity generation based on the thorium cycle remains an attractive concept. But its proclaimed virtues of a resource even more abundant than uranium (already huge with breeder reactors), better security, a lower production of waste, and a limitation of the proliferation of weapons need to be relativized.

Thorium is certainly a possible energy sector. Scientists and engineers had seen it well since the birth of civilian nuclear, but it is not a miracle industry. Those who seek to make it believe are primarily intended to counter the nuclear in general by discrediting the decisions and patient work of past and current leaders of the nuclear industry.

Thorium fuel is an interesting option for the distant future (beyond 2100?) Which deserves studies to be pursued without losing sight of industrial realities.

This article is inspired by a text by Hubert Flocard
The last show was on September 20th, 2016 on ARTE. ↩
In a pressurized water reactor, about one-third of the heat is produced by plutonium 239 from uranium-238. The rest comes from the fission of uranium-235.
Lecture by Dominique Grenéche
Broadcast on ARTE on September 20th, 2016: “Thorium, the wasted face of nuclear power”. ↩
Only certain Russian or CANDU (Canadian) reactors can produce military grade plutonium. ↩
PWR: Pressurized Water Reactor ↩