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An end to global warming
International Journal of Hydrogen Energy 30 (2005) 83 – 85
Book review An end to global warming L.O. Williams; Pergamon, Elsevier Science, Oxford, UK, 2002, 209pp The book is strongly suggestive of the time after the 3rst energy crisis in the 1970s and 1980s where the nuclear community has proposed, too, ‘Grand Designs’ for the asymptotic use of nuclear energy, both 3ssion and fusion as well as mixed systems, to replace the fossil fuel energy system. Although the driving force at that time was di
www.elsevier.com/locate/ijhydene
in order not to lose the red threat in the trains of thoughts of the academics involved. Furthermore, he is right when he argues that only new CO2 -free power stations can really cope with the CO2 -problem—and he is right when he believes that the Kyoto Treaty is only an epsilontic ansatz. But must this new energy source necessarily be fusion? What about the reality? The peaceful use of fusion power with plasma reactors has a long history of half a century and tens of billions US$ were spent worldwide for this kind of research (Williams estimates a cumulative sum of 100 billion US$)—without producing so far only one kWh of useful energy. The ITER-Tokamak fusion reactor project is a tragedy: Step by step the reactor con3guration was reduced to end up 3nally in construction costs of 3 billion US$—and nobody knows really if it will be ever built. The reviewer is also disappointed about this development, but I must ask the question: Can one really ask for a crash-programme in the TW-regime if no one demonstration reactor exists? Is it not too early? All that glitters is not gold with plasma fusion. Economically speaking, an inherent disadvantage is its relatively low-power density in the plasma (MW/m3 ), 40–50 times lower than in the core of a light water reactor and two orders of magnitude lower than in a breeder, resulting in large structures and therefore high capital costs. Its geometry is complicated and remote handling is necessary to exchange the 3rst walls regularly and, although the toxicity of the activated materials is lower and more short-lived than in a 3ssion reactor, one needs waste repositories, though. All this can probably be mastered in a technical sense, but to which price? Nobody knows. This situation, lasting now for decades, lead us to the conclusion: Near is my shirt, but nearer is my skin. Let us do the job with 3ssion where we have substantially more practical experience. Properly done 3ssion can do the same thing as L.O. Williams’ system with the same prospects concerning primary energy resources. With a safe conscience one can say that 3ssion has to be preferred. This does not mean that fusion is excluded ad in3nitum; if it joins us later, the better it is. The energy richness (and neutron poorness) of 3ssion and the neutron richness (and energy poorness) of fusion would complement one another in an ideal way via a commonly optimized neutron economy. Before we are coming, however, to the main question of energy and civilization, some smaller inaccuracies in Williams text must be corrected. For instance, if he speaks about burner reactors nuclear energy. When he states that ‘in the US the majority of the reactors are pressurized
84
Book review / International Journal of Hydrogen Energy 30 (2005) 83 – 85
water reactors with graphite moderators’ it is not clear what he means. No pressurized water reactor has a graphite moderator. Furthermore, he speaks about ‘isotopes that can 3ssion to produce energy are termed a ‘fertile’ isotope’. This is not the de3nition we have. We distinguish clearly between 3ssile, 3ssionable and fertile isotopes. ‘Fertile’—as in agriculture—is an isotope if it can capture a slow neutron to produce a new 3ssile isotope (e.g. Pu-239 from U-238). Fissile means that the corresponding isotope can best be 3ssioned by slow neutrons whereas 3ssionable includes a general 3ssion process, i.e. also by fast neutrons. Therefore, U-238 and Th-232 are simultaneously fertile and 3ssionable but not 3ssile. Sorry, but international nomenclature must be followed. Another aspect when speaking about the fuel resources of a huge DT-fusion reactor strategy are the lithium reserves which went too short in L.O. Williams’ programme. Not the (small) amount of lithium which has to be converted into tritium breeding determines the necessary resource basis. It is the (large) amounts of lithium which have to take an inventory of the blankets in the fusion reactors (& 1000 t=reactor), determine the resources—a fact being often overlooked when discussing DT-fusion programmes. Let us now come to the main energy self-criticality problem of civilization. All standard-bearers of any new energy source are subject to it—also L.O. Williams with his ambitious fusion strategy from which he optimistically believes that ‘the 3rst Fusion Hydrogen plant is 10–15 years away’. Exactly on the day when I—a native born German— had to write this book review we were celebrating the 200th day of the philosopher Imanuel Kant’s death in KKonigsberg/East-Prussia, the father of the German Enlightenment in the 18th century. He was not only the front-thinker for the later United Nations by his criticism of the pure and practical reason and his famous categorical imperative; in his later years he was also thinking about the criticism of the Power of Judgement where the notion of the ‘sublimity’ played an eminent role in the esthetics of the 3nding process for a judgement. The word sounds strange today but let us express with words of today what it means when we have to 3nd a 3nal judgement about L.O. Williams’ book. We can consider our present civilization as a self-organized dissipative system with a circular causality concerning the production of energy and the economical output. Such a system is characterized primarily by the amount of energy which is necessary to produce one US$ of the GDP. This value is at present for the US-economy I = 2:5 kWhth =$. We call I the energy intensity of the civilization under consideration; it can vary from country to country. On the other hand, if we build any new power station in this system speci3c energy cost, C, for the product will result in terms of $=kWhuseful . The same picture holds also for L.O. Williams Fusion Hydrogen system where C means the production costs of a kWh of useful hydrogen being fed into the system.
There is, however, a (dimensionless) condition which has to be ful3lled: 0 ¡ IC 1
(1)
or Ro =1=(IC) 1 where Ro is called the static harvest ratio. If IC was unity then all of the energy produced would be necessary to keep alive the energy system but no energy was available for the general economic process and for private consumption. If the product was ¿ 1 (or Ro ¡ 1) then we speak of an energy sink: The power plant is so ineMcient that it cannot guarantee its own survival in the steady state. In the case IC = 0 (or Ro = ∞) is not possible in practice because either I or C or both have to be zero. But this is only half of the truth since it considers only the steady state. In a dynamic situation, in which the installed power capacity should grow, the analysis shows that for an exponential growth (˙ exp(t=Tmin )) the minimum characteristic time constant, Tmin , has to ful3ll the condition T1 + T2 Tmin = ; (2) 2( Ro − 1) where T1 and T2 are the construction time and the useful lifetime of a power plant, respectively, and ¡ 1 is the fraction of the power output that has to be recycled to keep the system alive (normally is in the range 5% ¡ ¡ 10%). We can now distinguish three regimes: 1. If Ro ¡ 1, then Tmin is negative and the whole system decays dissipatively because it is driven by dynamical energy sinks. 2. If Ro = 1, then Tmin = ∞ and we are in steady state. No growth is possible, everything remains stable. 3. If Ro ¿ 1, then Tmin is positive and the system can grow according to Eq. (2) because it is driven by real dynamical energy sources. The larger the Ro , the smaller the Tmin and the faster the growth rate. In contrast to Eq. (1) Eq. (2) is called the dynamical critical equation of a self-organized system of civilization. Let us now check whether L.O. Williams fusion programme can ful3ll the above conditions. He wants to increase his fusion reactor capacity from 1 reactor to 2268 reactors within a period of half a century. This corresponds to a characteristic time of about 6.5 years. Introducing this 3gure into Eq. (2) and assuming optimistically that T1 =5 yr, T2 =40 yr and = 0:1, we 3nd Ro ≈ 45. Introducing this value into Eq. (1) we 3nd for I = 2:5 kWh=$ that the costs for his hydrogen must be smaller than C ≈ 0:9 US=kWh. This is at least one order of magnitude away from a thinkable reality— even the electrolytic step would be more expensive. To my sorrow, even as an advocatus diaboli of nuclear energy, I must say that L.O. Williams’ plan of a total investment far beyond 100 T$—being about 5 times the present annual World GDP—is too ambitious. We must go ahead step by step—the World will not be ready to spend 10% of its GDP over a period of half a century into such a business from which we do not have
Book review / International Journal of Hydrogen Energy 30 (2005) 83 – 85
a presentiment whether it really will turn out well. This does not mean a missing will to do something against the CO2 -problem. It has to do with Imanuel Kant’s principles of the Power of Judgement: ‘Be of good cheer to make use of your own reason’. Although the strategic aspects included in the book may be controversial, hydrogen energy scientists and engineers who are involved in 3nding a permanent solution to the intertwined global energy and environmental problems may 3nd the fusion approach quite interesting and worthwhile to consider—provided that the corresponding and necessary
85
progress in the future fusion reactor demonstration phase will be made and fusion energy really turns out to become a viable and economic energy source. In any case the book itself is readable and recommendable if only because it presents an integral view on one of the most grave problems of mankind. Walter Seifritz MKulacherstr. 44; CH-5212 Hausen; Switzerland
Book review An end to global warming L.O. Williams; Pergamon, Elsevier Science, Oxford, UK, 2002, 209pp The book is strongly suggestive of the time after the 3rst energy crisis in the 1970s and 1980s where the nuclear community has proposed, too, ‘Grand Designs’ for the asymptotic use of nuclear energy, both 3ssion and fusion as well as mixed systems, to replace the fossil fuel energy system. Although the driving force at that time was di
www.elsevier.com/locate/ijhydene
in order not to lose the red threat in the trains of thoughts of the academics involved. Furthermore, he is right when he argues that only new CO2 -free power stations can really cope with the CO2 -problem—and he is right when he believes that the Kyoto Treaty is only an epsilontic ansatz. But must this new energy source necessarily be fusion? What about the reality? The peaceful use of fusion power with plasma reactors has a long history of half a century and tens of billions US$ were spent worldwide for this kind of research (Williams estimates a cumulative sum of 100 billion US$)—without producing so far only one kWh of useful energy. The ITER-Tokamak fusion reactor project is a tragedy: Step by step the reactor con3guration was reduced to end up 3nally in construction costs of 3 billion US$—and nobody knows really if it will be ever built. The reviewer is also disappointed about this development, but I must ask the question: Can one really ask for a crash-programme in the TW-regime if no one demonstration reactor exists? Is it not too early? All that glitters is not gold with plasma fusion. Economically speaking, an inherent disadvantage is its relatively low-power density in the plasma (MW/m3 ), 40–50 times lower than in the core of a light water reactor and two orders of magnitude lower than in a breeder, resulting in large structures and therefore high capital costs. Its geometry is complicated and remote handling is necessary to exchange the 3rst walls regularly and, although the toxicity of the activated materials is lower and more short-lived than in a 3ssion reactor, one needs waste repositories, though. All this can probably be mastered in a technical sense, but to which price? Nobody knows. This situation, lasting now for decades, lead us to the conclusion: Near is my shirt, but nearer is my skin. Let us do the job with 3ssion where we have substantially more practical experience. Properly done 3ssion can do the same thing as L.O. Williams’ system with the same prospects concerning primary energy resources. With a safe conscience one can say that 3ssion has to be preferred. This does not mean that fusion is excluded ad in3nitum; if it joins us later, the better it is. The energy richness (and neutron poorness) of 3ssion and the neutron richness (and energy poorness) of fusion would complement one another in an ideal way via a commonly optimized neutron economy. Before we are coming, however, to the main question of energy and civilization, some smaller inaccuracies in Williams text must be corrected. For instance, if he speaks about burner reactors nuclear energy. When he states that ‘in the US the majority of the reactors are pressurized
84
Book review / International Journal of Hydrogen Energy 30 (2005) 83 – 85
water reactors with graphite moderators’ it is not clear what he means. No pressurized water reactor has a graphite moderator. Furthermore, he speaks about ‘isotopes that can 3ssion to produce energy are termed a ‘fertile’ isotope’. This is not the de3nition we have. We distinguish clearly between 3ssile, 3ssionable and fertile isotopes. ‘Fertile’—as in agriculture—is an isotope if it can capture a slow neutron to produce a new 3ssile isotope (e.g. Pu-239 from U-238). Fissile means that the corresponding isotope can best be 3ssioned by slow neutrons whereas 3ssionable includes a general 3ssion process, i.e. also by fast neutrons. Therefore, U-238 and Th-232 are simultaneously fertile and 3ssionable but not 3ssile. Sorry, but international nomenclature must be followed. Another aspect when speaking about the fuel resources of a huge DT-fusion reactor strategy are the lithium reserves which went too short in L.O. Williams’ programme. Not the (small) amount of lithium which has to be converted into tritium breeding determines the necessary resource basis. It is the (large) amounts of lithium which have to take an inventory of the blankets in the fusion reactors (& 1000 t=reactor), determine the resources—a fact being often overlooked when discussing DT-fusion programmes. Let us now come to the main energy self-criticality problem of civilization. All standard-bearers of any new energy source are subject to it—also L.O. Williams with his ambitious fusion strategy from which he optimistically believes that ‘the 3rst Fusion Hydrogen plant is 10–15 years away’. Exactly on the day when I—a native born German— had to write this book review we were celebrating the 200th day of the philosopher Imanuel Kant’s death in KKonigsberg/East-Prussia, the father of the German Enlightenment in the 18th century. He was not only the front-thinker for the later United Nations by his criticism of the pure and practical reason and his famous categorical imperative; in his later years he was also thinking about the criticism of the Power of Judgement where the notion of the ‘sublimity’ played an eminent role in the esthetics of the 3nding process for a judgement. The word sounds strange today but let us express with words of today what it means when we have to 3nd a 3nal judgement about L.O. Williams’ book. We can consider our present civilization as a self-organized dissipative system with a circular causality concerning the production of energy and the economical output. Such a system is characterized primarily by the amount of energy which is necessary to produce one US$ of the GDP. This value is at present for the US-economy I = 2:5 kWhth =$. We call I the energy intensity of the civilization under consideration; it can vary from country to country. On the other hand, if we build any new power station in this system speci3c energy cost, C, for the product will result in terms of $=kWhuseful . The same picture holds also for L.O. Williams Fusion Hydrogen system where C means the production costs of a kWh of useful hydrogen being fed into the system.
There is, however, a (dimensionless) condition which has to be ful3lled: 0 ¡ IC 1
(1)
or Ro =1=(IC) 1 where Ro is called the static harvest ratio. If IC was unity then all of the energy produced would be necessary to keep alive the energy system but no energy was available for the general economic process and for private consumption. If the product was ¿ 1 (or Ro ¡ 1) then we speak of an energy sink: The power plant is so ineMcient that it cannot guarantee its own survival in the steady state. In the case IC = 0 (or Ro = ∞) is not possible in practice because either I or C or both have to be zero. But this is only half of the truth since it considers only the steady state. In a dynamic situation, in which the installed power capacity should grow, the analysis shows that for an exponential growth (˙ exp(t=Tmin )) the minimum characteristic time constant, Tmin , has to ful3ll the condition T1 + T2 Tmin = ; (2) 2( Ro − 1) where T1 and T2 are the construction time and the useful lifetime of a power plant, respectively, and ¡ 1 is the fraction of the power output that has to be recycled to keep the system alive (normally is in the range 5% ¡ ¡ 10%). We can now distinguish three regimes: 1. If Ro ¡ 1, then Tmin is negative and the whole system decays dissipatively because it is driven by dynamical energy sinks. 2. If Ro = 1, then Tmin = ∞ and we are in steady state. No growth is possible, everything remains stable. 3. If Ro ¿ 1, then Tmin is positive and the system can grow according to Eq. (2) because it is driven by real dynamical energy sources. The larger the Ro , the smaller the Tmin and the faster the growth rate. In contrast to Eq. (1) Eq. (2) is called the dynamical critical equation of a self-organized system of civilization. Let us now check whether L.O. Williams fusion programme can ful3ll the above conditions. He wants to increase his fusion reactor capacity from 1 reactor to 2268 reactors within a period of half a century. This corresponds to a characteristic time of about 6.5 years. Introducing this 3gure into Eq. (2) and assuming optimistically that T1 =5 yr, T2 =40 yr and = 0:1, we 3nd Ro ≈ 45. Introducing this value into Eq. (1) we 3nd for I = 2:5 kWh=$ that the costs for his hydrogen must be smaller than C ≈ 0:9 US=kWh. This is at least one order of magnitude away from a thinkable reality— even the electrolytic step would be more expensive. To my sorrow, even as an advocatus diaboli of nuclear energy, I must say that L.O. Williams’ plan of a total investment far beyond 100 T$—being about 5 times the present annual World GDP—is too ambitious. We must go ahead step by step—the World will not be ready to spend 10% of its GDP over a period of half a century into such a business from which we do not have
Book review / International Journal of Hydrogen Energy 30 (2005) 83 – 85
a presentiment whether it really will turn out well. This does not mean a missing will to do something against the CO2 -problem. It has to do with Imanuel Kant’s principles of the Power of Judgement: ‘Be of good cheer to make use of your own reason’. Although the strategic aspects included in the book may be controversial, hydrogen energy scientists and engineers who are involved in 3nding a permanent solution to the intertwined global energy and environmental problems may 3nd the fusion approach quite interesting and worthwhile to consider—provided that the corresponding and necessary
85
progress in the future fusion reactor demonstration phase will be made and fusion energy really turns out to become a viable and economic energy source. In any case the book itself is readable and recommendable if only because it presents an integral view on one of the most grave problems of mankind. Walter Seifritz MKulacherstr. 44; CH-5212 Hausen; Switzerland