Long Range Projections of Alternative Energy Futures
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Koopmans, Tjalling C.
Since the very beginning in 1951, the Lindau meetings were dedicated to medicine, chemistry and physics. But when the Royal Swedish Academy of Sciences and the Nobel Foundation in 1968 agreed to take on a new prize in economic sciences to the memory of Alfred Nobel, the Laureates of this prize were also invited to Lindau. Ragnar Frisch, one of the two co-Laureates who received the new prize when it was given for the first time in 1969, lectured at the Lindau meeting already 1971. During the 1970’s, several of the new economic Laureates visited the meetings, but the second to give a formal lecture was Tjalling Koopmans 1982. By the time he came to Lindau he had regained his gold medal, which was mixed up with the medal of his co-Laureate Leonid Kantarovich in 1975 and which spent four years in the Soviet Union before returning to the west! Koopmans was a former theoretical physicist who seemed to feel at home with the physicists at the 1982 meeting. Among many other things, he had acted as chairman of the Modelling Resource Group of the Committee on Nuclear and Alternative Energy Systems of the National Academy of Sciences of the US. This committee had the task of making long-range projections well into the 21st century. One of Koopmans’ specialities was the application of the techniques of optimization over time, in this case as applied to the field of the supply of energy, and this was the topic of his talk in Lindau. It is a pity that we don’t have access to his viewgraphs, but from the spoken word it is clear that many of the questions that are at the forefront today were already present some 30 years ago. This goes, e.g., for the side effects of using fossil fuels, which is discussed by Koopmans mainly in economic terms. In particular the emission of CO2 into the atmosphere, leading to the greenhouse effect, was already there in this 1982 lecture! Anders Bárány
 It is a great honor to be invited to address this gathering and also it is a very fine development that different professions which together are needed in collaboration in order to face up to the many problems that modern technology and modern society has presented us with. So I am glad for two reasons. The second being to be allowed to participate in interdisciplinary activity. I am worried that our universities are not designed and organized to make it easy to find these collaborations but outside universities there are other search opportunities and in particular the tagungen in Lindau have that character. Now my topic then is long range projections of alternative energy futures which is one particular study in the field of energy modeling itself a development of the last 10 to 12 years. I forgot to ask the chairman to let me know when I am five minutes before the end of my talk so please tell me when I have only five minutes left. The development of energy modeling took place in United States, in Europe, Mexico, India and other countries. The aim of that technique is to visualize alternative energy futures. The nature of the problem draws, makes one need to draw on various fields of knowledge and actually some speculation. Technological knowledge to draw on physics, chemistry, biology, engineering, behavioral to draw on economics in regard to the behavior of consumers and of producers faced with the market and the resource availability problems in which we need to turn to geologists and mining engineering. There is in this type of work a speculative element and that is inevitable in models that look far ahead into the future. For that reason the conclusions reached have the following logical form. If such and such then so and so. And the ifs must be emphasized if you find that someone reports on a model study and those are my conclusions and that person only gives the thens and not the ifs then that is unsatisfactory. Now I would like tend to use one recent modeling study in which I was involved that illustrates the type of work along these lines. There was in the United States a very substantial and widely ramifying study of energy futures and energy presence called by the committee on nuclear and alternative energy systems, a committee set up by a combination of the National Academy of Sciences and the National Academy of Engineering. There was an overview committee that was responsible for the ultimate publication, a very substantial book that has come out of that work. There were also panels to provide analytical work into the mill so to say of the deliberation of the overview committee and I was chairman of a panel called modeling resource group. Now the word resource in that sentence is human resources, experts, resources of expertise. The assignment of that group was to answer, to compare the answers given to the same set of questions by three different models that were already available before the work was started. My emphasis in this report is on the methods and on the kinds of questions that can be answered. And therefore the ifs that we did use and we had several alternative ifs side by side should be revised as time goes on and any results if I may use that word of this particular study would have to be revised as the ifs are revised. Now I have, can we dim the top light a bit enough now for the, I have to switch this on. This diagram is in a way a layout of the study. We did consider three groups of variables, the driving variables, the realization variables, excuse me, the word realization was used by something for something that is not subject to policy decisions. It is there already or it is caused by circumstances and decisions that the energy related policies do not have an effect on or a sizable effect on. Now we had there the GNP growth rate as one, you may also say exogenous variable and that was estimated on the basis of population extension, labor force participation and such factors at 3.2 per annum from the beginning year of the study which was 1975 up to 2010. Then another realization value was cost levels of energy technologies. At that point we did not have the subsequent experience and so we had the following figures in terms of dollars of 1975. The figures are for capital cost of electricity generation, the coal fire generation we had $520 of 1975 per kilowatt electric. Light water reactor, the number goes up to 650. Advanced converter reactor 715. Fast breather reactor 810, again dollars of 1975 per kilowatt electric and solar central station 1730 of in the same unit. Now these numbers have all gone up since then so I report on the study as made at that time without trying to bring up to date any numbers. We also had resource stock availability numbers on there for oil and gas. It was in the United States a quantity of 1,720 quads where one quad is 10 to the 15th BTU and this was oil and gas at a cost of extraction up to $2 of 1975 per million BTU. For uranium it was 3.710 to the 6th tons of U308 at a cost of extraction not exceeding $30 in that same unit. Now then it says there on the right demand elasticity with regard to price and with regard to income. It turned out to at the end of the study that was an extremely important parameter and I will come back later to its precise definition. It is a measure of the response of demand to a given increase of price and a given increase of income. I have a slide later that will indicate both the numbers used and the definitions of the concepts. In any case the three important models that we used differed in their price elasticity and that was in fact helpful because it indicated the importance of that parameter. Now the models that were used we had 3 plus 4, 7, no 6 models actually in the study but the only ones long enough looking into the future were DSOM, ETA and North House, STARD and I will refer to those in more detail later on. Then we had policy variables. First of all, base case which was going on pretty much with the developments as they are presently called for and that is called the base case and then we had other cases that are obtained from the base case by policies that were in there because they were much under discussion at the time. The nuclear moratoria was not then considered as a policy since then something in that direction has taken place, not really as a policy but as a result of mishaps and fears so it is desirable to have this in the study regardless of whether or how such a containment might come about. It was defined, nuclear moratorium in the case of applied to all nuclear reactors was one case, another case was to apply it not to the light water reactors already in service for quite some time and it was so these two cases were distinguished. Also limits on the use of coal and oil shale coal because of the acid rain and oil shale as a result of water use and water deterioration as a result of use and in both cases or in the case of all fossil fuels there is also a long range concern with the CO2 content of the atmosphere. So that's the reason why that is in there also and these limits were defined, we won't give the figures, by drawing some curves that would level off to an asymptote in case of coal and another curve in the case of shale oil and the limits would be that at no point would the annual rate of production of coal or shale oil exceed that curve. Now then finally we had a third category of variables that we called blend variables which are called blend variables because they combine the properties of realization variables and a policies. The discount rates as we have found to our dismay in the United States are also subject to policy but they are also in the absence of specific determined policy still are a reflection of the behavior of parties in the capital market of the economy and so that is a blend variable that we ended up using 13 percent for pre-tax discount rates applied to investment and pricing decisions of the energy producing business forms industry and 6 percent post tax applied to the consumers relative weight to future benefit given to future benefits as compared with present benefits for that we had a 6 percent discount rate. Then there was a ceiling on quantity and price of imports of fuels that I will not dwell on and an estimate of the commercial availability if wanted of advanced converter reactors fast breeder reactors or solar electricity generation all assumed to be available at and from the year 2000 if that were to be aimed for. Then the technique on the ideas on the economic side were that optimization optimization is can be looked at as a simulation of the behavior of competitive market systems. I like to put it this way there is in the world neither come perfect competition nor perfect planning but if there were then they would be equivalent the perfect planning would be guided by prices similar to those produced by perfect competition or producible by perfect competition as well so that we have had this fictitious image of efficiency and use of resources and it doesn't matter how it is obtained assuming it can be obtained. It was meant to be actually an approximation of how our not quite perfect system of markets operates. So you could say we used Adam Smith's invisible hand but with foresight. Now then the price and income elasticity of demand for energy I'm now ready to say some more about that. Here are the numbers that we in fact used and now I also want to define the price elasticity that was the most important of the two. Let X be the demand and P the price the demand for energy and the price of energy in terms of some aggregates over the various forms of energy just one number then the elasticity is defined as the derivative of the log of quantity demanded with respect to the log of price in the market and that is as you see from the use of logs a dimensionless quantity. Now there were if policies that constrain energy supply are strong I replied strongly then a high price increase is needed to constrain demand accordingly and if the absolute yes I should have said the each normally each price elasticity of demand is a negative number because as price goes up quantity demanded goes down now I go back to my sentence a high price increase is then needed to constrain demand accordingly and if in absolute value the elasticity is low and less than less remains to spend on other goods. If the absolute value of the elasticity is high then only a smaller price increase results and the amounts spent on other goods are less affected and the total of GMP of gross national product is less affected. This sort of simple straightforward reasoning indicates that ADA the price elasticity of demand that negative number is a very critical parameter and I like to mention also I will first describe the elasticity that have been used in the study. Here DSOM was a model developed at Brookhaven laboratory and for reasons that were connected with the purpose of that model it did not have consumers response dependent on price it just projected the curve of consumers demand as a function of time into the future up to 2000 and for that reason the price elasticity of demand was really very small the only sensitivity or response to price was still in the choice of the particular energy technology conversion transport or what a certain sensitivity to price came out before the energy reached the consumer. Then the other two models were quite similar in structure the energy technology assessment model of Alan Mann at Stanford University distinguished electric and non-electric demands and it came to an estimate of minus point two five so absolute value of the elasticity of one fourth. The North house model had more subdivisions one residential and commercial users two industrial three transportation for specific electric services that could only be done by electric power and he came at an eight out of minus point four the there was a study done subsequently by the energy modeling forum an organization based on Stanford University but operating nationwide with the nationwide following and participants of the elasticity values that had been produced by various studies by econometric methods statistical methods as against judgmental estimates. Now the modeling forum had found a range of minus point four to minus point seven of those obtained by statistical those estimates obtained by statistical and econometric methods the minus point two five in the man model was labeled as a judgmental estimate. But at the request of other members in the group Alan Mann who was himself a member of the committee of the modeling resource group and so was North house and so were two people from Brookhaven and the group the estimate that since the estimate was we didn't use that term at that time had some judgmental aspect to it we asked man and he willingly did add a second minus point five oh I have five minutes thank you then they I will go and jump now to the results that came out of the here we have to look carefully at the definitions of what is on the axis. I think I first must list the policies here the policies were those that they had already enumerated namely the base case and then the moratorium only on advanced converter and breeder reactors then moratorium on all reactors and then the coal and shale limits those were the first assumptions and then certain combinations the moratorium on both the moratorium and the coal and shale limits and of those the following diagrams indicate what was found and let's now read carefully what is on these axis here we have e the ratio of aggregate energy consumption in 2010 projected for policy I that is the one of that list of five that refers and that ratio is set off here so the more drastic the policy the further the point corresponding to it will be down on this axis the other is the ratio of cumulative discounted GNP for 1975 to 2010 projected again for the same policy and then which model that is in indicated by the particular symbol that is there to indicate the dot and that here are the three D some responses to policy and that's the only one until we get there where there is a direct response to some constraining measures with regard to consumption used. Therefore we have been note then that all the other points somehow heard the vertical line and that indicates that quite that where the elasticity is that are no longer there on the screen are moderately high from minus point four on the points remain and the effect on GNP of the constraints on energy use are not severe however in this this point here the this is the eta point at minus point two five price elasticity a constraint in quantity that has an effect this much then also the GNP is constrained so here we see it very clearly before us from these measurements that it depends on the price elasticity of demand in the model that is perceived that is produced by the model. Now let me then just miscalculated my time somewhat but let me just then indicate my summary of what was learned from this study the first of all the smallness of the effect on GNP as long as you don't get below let's say minus point five or minus point four in if in the price elasticity and it is a matter of econometric work to improve the assurance that we can have in reading these estimates but I do read maybe a little ahead of myself that the principal conclusion that I draw is that there is some time left to overcome the problems of widespread concern with the safety of nuclear reactors including the breeder reactors and this is important because if we mostly rely on fossil fuels we have to deal also with their side effects the acid rain or the CO2 in the atmosphere the acid rain mostly from coal but the CO2 problem as much from oil and gas if those are to be the main state so I read out of this study first of all it's a first study of its kind therefore provisional and not to be dogmatic about but second also it indicates that there is enough time to try out alternative methods of energy generation or rather the mix there of we are not under the sword of demo class thank you.
 It is a great honor to be invited to address this gathering and also it is a very fine  development that different professions which together are needed in collaboration in order  to face up to the many problems that modern technology and modern society has presented  us with. So I am glad for two reasons. The second being to be allowed to participate  in interdisciplinary activity. I am worried that our universities are not designed and  organized to make it easy to find these collaborations but outside universities there are other search  opportunities and in particular the tagungen in Lindau have that character. Now my topic  then is long range projections of alternative energy futures which is one particular study  in the field of energy modeling itself a development of the last 10 to 12 years. I forgot to ask  the chairman to let me know when I am five minutes before the end of my talk so please  tell me when I have only five minutes left. The development of energy modeling took place  in United States, in Europe, Mexico, India and other countries. The aim of that technique  is to visualize alternative energy futures. The nature of the problem draws, makes one  need to draw on various fields of knowledge and actually some speculation. Technological  knowledge to draw on physics, chemistry, biology, engineering, behavioral to draw on economics  in regard to the behavior of consumers and of producers faced with the market and the  resource availability problems in which we need to turn to geologists and mining engineering.  There is in this type of work a speculative element and that is inevitable in models that  look far ahead into the future. For that reason the conclusions reached have the following  logical form. If such and such then so and so. And the ifs must be emphasized if you  find that someone reports on a model study and those are my conclusions and that person  only gives the thens and not the ifs then that is unsatisfactory.  Now I would like tend to use one recent modeling study in which I was involved that illustrates  the type of work along these lines. There was in the United States a very substantial  and widely ramifying study of energy futures and energy presence called by the committee  on nuclear and alternative energy systems, a committee set up by a combination of the  National Academy of Sciences and the National Academy of Engineering. There was an overview  committee that was responsible for the ultimate publication, a very substantial book that  has come out of that work. There were also panels to provide analytical work into the  mill so to say of the deliberation of the overview committee and I was chairman of a panel called  modeling resource group. Now the word resource in that sentence is human resources, experts,  resources of expertise. The assignment of that group was to answer, to compare the answers  given to the same set of questions by three different models that were already available  before the work was started. My emphasis in this report is on the methods and on the kinds  of questions that can be answered. And therefore the ifs that we did use and we had several  alternative ifs side by side should be revised as time goes on and any results if I may use  that word of this particular study would have to be revised as the ifs are revised. Now  I have, can we dim the top light a bit enough now for the, I have to switch this on. This  diagram is in a way a layout of the study. We did consider three groups of variables,  the driving variables, the realization variables, excuse me, the word realization was used by  something for something that is not subject to policy decisions. It is there already or  it is caused by circumstances and decisions that the energy related policies do not have  an effect on or a sizable effect on. Now we had there the GNP growth rate as one, you  may also say exogenous variable and that was estimated on the basis of population extension,  labor force participation and such factors at 3.2 per annum from the beginning year of  the study which was 1975 up to 2010. Then another realization value was cost levels  of energy technologies. At that point we did not have the subsequent experience and so  we had the following figures in terms of dollars of 1975. The figures are for capital cost of  electricity generation, the coal fire generation we had $520 of 1975 per kilowatt electric.  Light water reactor, the number goes up to 650. Advanced converter reactor 715. Fast  breather reactor 810, again dollars of 1975 per kilowatt electric and solar central station  1730 of in the same unit. Now these numbers have all gone up since then so I report on  the study as made at that time without trying to bring up to date any numbers. We also had  resource stock availability numbers on there for oil and gas. It was in the United States  a quantity of 1,720 quads where one quad is 10 to the 15th BTU and this was oil and gas  at a cost of extraction up to $2 of 1975 per million BTU. For uranium it was 3.710 to the  6th tons of U308 at a cost of extraction not exceeding $30 in that same unit. Now then  it says there on the right demand elasticity with regard to price and with regard to income.  It turned out to at the end of the study that was an extremely important parameter and I  will come back later to its precise definition. It is a measure of the response of demand  to a given increase of price and a given increase of income. I have a slide later that will  indicate both the numbers used and the definitions of the concepts. In any case the three important  models that we used differed in their price elasticity and that was in fact helpful because  it indicated the importance of that parameter. Now the models that were used we had 3 plus  4, 7, no 6 models actually in the study but the only ones long enough looking into the  future were DSOM, ETA and North House, STARD and I will refer to those in more detail later  on. Then we had policy variables. First of all, base case which was going on pretty much  with the developments as they are presently called for and that is called the base case  and then we had other cases that are obtained from the base case by policies that were in  there because they were much under discussion at the time. The nuclear moratoria was not  then considered as a policy since then something in that direction has taken place, not really  as a policy but as a result of mishaps and fears so it is desirable to have this in the  study regardless of whether or how such a containment might come about. It was defined,  nuclear moratorium in the case of applied to all nuclear reactors was one case, another  case was to apply it not to the light water reactors already in service for quite some  time and it was so these two cases were distinguished. Also limits on the use of coal and oil shale  coal because of the acid rain and oil shale as a result of water use and water deterioration  as a result of use and in both cases or in the case of all fossil fuels there is also  a long range concern with the CO2 content of the atmosphere. So that's the reason why  that is in there also and these limits were defined, we won't give the figures, by drawing  some curves that would level off to an asymptote in case of coal and another curve in the case  of shale oil and the limits would be that at no point would the annual rate of production  of coal or shale oil exceed that curve. Now then finally we had a third category of variables  that we called blend variables which are called blend variables because they combine the properties  of realization variables and a policies. The discount rates as we have found to our dismay  in the United States are also subject to policy but they are also in the absence of specific  determined policy still are a reflection of the behavior of parties in the capital market  of the economy and so that is a blend variable that we ended up using 13 percent for pre-tax  discount rates applied to investment and pricing decisions of the energy producing business  forms industry and 6 percent post tax applied to the consumers relative weight to future  benefit given to future benefits as compared with present benefits for that we had a 6  percent discount rate. Then there was a ceiling on quantity and price of imports of fuels  that I will not dwell on and an estimate of the commercial availability if wanted of advanced  converter reactors fast breeder reactors or solar electricity generation all assumed to  be available at and from the year 2000 if that were to be aimed for. Then the technique  on the ideas on the economic side were that optimization optimization is can be looked  at as a simulation of the behavior of competitive market systems. I like to put it this way there  is in the world neither come perfect competition nor perfect planning but if there were then  they would be equivalent the perfect planning would be guided by prices similar to those  produced by perfect competition or producible by perfect competition as well so that we  have had this fictitious image of efficiency and use of resources and it doesn't matter  how it is obtained assuming it can be obtained. It was meant to be actually an approximation  of how our not quite perfect system of markets operates. So you could say we used Adam Smith's  invisible hand but with foresight. Now then the price and income elasticity of demand  for energy I'm now ready to say some more about that. Here are the numbers that we in  fact used and now I also want to define the price elasticity that was the most important  of the two. Let X be the demand and P the price the demand for energy and the price  of energy in terms of some aggregates over the various forms of energy just one number  then the elasticity is defined as the derivative of the log of quantity demanded with respect  to the log of price in the market and that is as you see from the use of logs a dimensionless  quantity. Now there were if policies that constrain energy supply are strong I replied  strongly then a high price increase is needed to constrain demand accordingly and if the  absolute yes I should have said the each normally each price elasticity of demand is a negative  number because as price goes up quantity demanded goes down now I go back to my sentence a high  price increase is then needed to constrain demand accordingly and if in absolute value  the elasticity is low and less than less remains to spend on other goods. If the absolute value  of the elasticity is high then only a smaller price increase results and the amounts spent  on other goods are less affected and the total of GMP of gross national product is less affected.  This sort of simple straightforward reasoning indicates that ADA the price elasticity of  demand that negative number is a very critical parameter and I like to mention also I will  first describe the elasticity that have been used in the study. Here DSOM was a model developed  at Brookhaven laboratory and for reasons that were connected with the purpose of that model  it did not have consumers response dependent on price it just projected the curve of consumers  demand as a function of time into the future up to 2000 and for that reason the price elasticity  of demand was really very small the only sensitivity or response to price was still in the choice  of the particular energy technology conversion transport or what a certain sensitivity to  price came out before the energy reached the consumer. Then the other two models were quite  similar in structure the energy technology assessment model of Alan Mann at Stanford  University distinguished electric and non-electric demands and it came to an estimate of minus  point two five so absolute value of the elasticity of one fourth. The North house model had more  subdivisions one residential and commercial users two industrial three transportation  for specific electric services that could only be done by electric power and he came  at an eight out of minus point four the there was a study done subsequently by the energy  modeling forum an organization based on Stanford University but operating nationwide with  the nationwide following and participants of the elasticity values that had been produced  by various studies by econometric methods statistical methods as against judgmental estimates.  Now the modeling forum had found a range of minus point four to minus point seven of those  obtained by statistical those estimates obtained by statistical and econometric methods the  minus point two five in the man model was labeled as a judgmental estimate. But at the  request of other members in the group Alan Mann who was himself a member of the committee  of the modeling resource group and so was North house and so were two people from Brookhaven  and the group the estimate that since the estimate was we didn't use that term at that time had  some judgmental aspect to it we asked man and he willingly did add a second minus point  five oh I have five minutes thank you then they I will go and jump now to the results  that came out of the here we have to look carefully at the definitions of what is on the axis.  I think I first must list the policies here the policies were those that they had already  enumerated namely the base case and then the moratorium only on advanced converter and  breeder reactors then moratorium on all reactors and then the coal and shale limits those were  the first assumptions and then certain combinations the moratorium on both the moratorium and  the coal and shale limits and of those the following diagrams indicate what was found  and let's now read carefully what is on these axis here we have e the ratio of aggregate  energy consumption in 2010 projected for policy I that is the one of that list of five that  refers and that ratio is set off here so the more drastic the policy the further the point  corresponding to it will be down on this axis the other is the ratio of cumulative discounted  GNP for 1975 to 2010 projected again for the same policy and then which model that is in  indicated by the particular symbol that is there to indicate the dot and that here are  the three D some responses to policy and that's the only one until we get there where there  is a direct response to some constraining measures with regard to consumption used.  Therefore we have been note then that all the other points somehow heard the vertical  line and that indicates that quite that where the elasticity is that are no longer there  on the screen are moderately high from minus point four on the points remain and the effect  on GNP of the constraints on energy use are not severe however in this this point here  the this is the eta point at minus point two five price elasticity a constraint in quantity  that has an effect this much then also the GNP is constrained so here we see it very  clearly before us from these measurements that it depends on the price elasticity of  demand in the model that is perceived that is produced by the model.  Now let me then just miscalculated my time somewhat but let me just then indicate my  summary of what was learned from this study the first of all the smallness of the effect  on GNP as long as you don't get below let's say minus point five or minus point four in  if in the price elasticity and it is a matter of econometric work to improve the assurance  that we can have in reading these estimates but I do read maybe a little ahead of myself  that the principal conclusion that I draw is that there is some time left to overcome  the problems of widespread concern with the safety of nuclear reactors including the breeder  reactors and this is important because if we mostly rely on fossil fuels we have to  deal also with their side effects the acid rain or the CO2 in the atmosphere the acid  rain mostly from coal but the CO2 problem as much from oil and gas if those are to be  the main state so I read out of this study first of all it's a first study of its kind  therefore provisional and not to be dogmatic about but second also it indicates that there  is enough time to try out alternative methods of energy generation or rather the mix there  of we are not under the sword of demo class thank you.
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