material-deontologia-biologica-capitulo26

Biological Ethics

Table of contents

Chapter 26. Energy crisis

N. López Moratalla

(a) Energy sources

A highly topical area for science - and to some extent for biology - is the global energy problem. Technology is faced with the urgent need to prepare for a progressive transition to new and varied forms of energy, which will reduce the predominance of the current use of fossil fuels, which are being depleted. This is a priority area of scientific and technical research cooperation between science and society.

There is, to some extent, a general ethical obligation for the scientist to carry out a research within his or her capabilities and means, towards those areas where there is the greatest need. It is obvious that this obligation, which also falls on those in society who plan research and direct science policy, does not affect everyone directly. However, every scientist can make a contribution with a rigorous knowledge of topic, which allows for responsible collaboration in the task of information and serves as a stimulus in the search for solutions.

Mc Divitt -director of UNESCO's Division of Science research and teaching - has pointed out that information is an indispensable factor in this problem: "Why have technological breakthroughs in the development of renewable and clean energy sources not been followed by their immediate and widespread application and use? There is no single answer to this complex problem, but it is generally accepted that the obstacles are not technical. Among those identified in the international programs of study that UNESCO has carried out on this subject are the lack of specialised information and public information, and the scarcity of scientific staff concerning the installations and their repair. One such programs of study, on Education and training at subject, sample , for example, states that despite the enormous interest in new energy sources, no systematic programme has yet been developed to meet the pressing need for skilled manpower. The survey, which covers some 300 institutions in 86 countries, shows that just as there is a need to provide training for researchers, technicians and engineers in all aspects of new energy technology, there is also a need to develop courses for decision-makers in this field.

In many cases, lack of information is the biggest obstacle to a more effective training and a better knowledge of the public on the possibilities of new energy sources. Even in countries with modern information systems, it is virtually impossible today to keep abreast of new technical developments, due to the sheer volume of publications and widely dispersed sources of information. There is widespread concern about the dangers of investments based on unreliable information. Users prefer to avoid the over-enthusiasm shown in certain circles for certain alternative energy sources, the results and performance of which can be a disappointment. All are aware that the choice of an alternative energy source could be subject to direct or indirect pressure from those involved in the promotion and sale of the materials and installations required for it"1.

Over the centuries, the types of energy available, as well as the ways in which it is used, have been one of the factors influencing ways of life, and even, in some respects, the social structure itself. The large-scale use of coal, together with other factors - invention of the steam engine, progress in the Chemistry and iron and steel industry - transformed agrarian societies with the first industrial revolution. Electricity also changed lifestyles and made possible the training of today's large urban centres. Since the 20th century, fossil fuels and hydroelectric and nuclear energy have enabled industrialised societies to advance.

The use of new, multiple and renewable energy sources is now necessary, as it would not be possible to meet the world's needs if the limited non-renewable resources available were to continue to be exploited exclusively.

Scientific knowledge is more than sufficient to obtain energy to meet the needs of today's society; the technical problem is the high cost of investment in the exploitation of renewable sources and the social and technological structural changes involved in the progressive use of new sources. Man is "wise" enough to release this energy from natural resources. What is necessary is for him to be wise enough to master and properly direct the energy forces he releases.

The energy that will be needed by the year 2000 will be in the order of 20.5 terewatts (a terewatt -TW- being one trillion watts), assuming a population increase from 5.5 to 6.7 billion human beings, and that the average consumption per person will increase from 2.2 KW today to 3.06, i.e. slightly less than double the current level. The main energy sources will be:

-Fossil fuels, such as coal, oil, natural gas and oil sands and shale;

-nuclear energy obtained from the conversion of mass into energy, by fission or fusion reactions;

-tidal power from the tides, which accumulate about 3 TW;

-that of the waves of the oceans;

-wind energy: some 2,700 TW are stored in the winds that blow over the earth;

-the hydraulics released in the cycle by which evaporated water falls back as rain or snow;

-in ocean currents there are accumulations of 5 to 8 TW;

-solar energy and energy from solar fuels, i.e. photosynthetic plants;

-geothermal: heat from rocks, thermal waters, volcanoes.

Nuclear energy, due to its nature and the risks involved in its use - we are now referring exclusively to its use as an energy source source - requires some considerations.

(b) Use of nuclear energy

Theoretically, nuclear energy could come from fusion or atomic fission. At present, only fission is used, as the technique required to obtain the fusion of atoms in a controlled manner has not yet been developed. We will briefly analyse three types of nuclear reactions, which will give us a better understanding of the possibilities and limitations of nuclear power plants, with emphasis on the risks involved.

Fission reaction: This is achieved by bombarding atoms with high-energy particles, specifically neutrons, which have no electrical charge and can collide with the nucleus; when the atom is split into fission products, a large amount of energy is produced and new neutrons are released; these neutrons can break other nuclei, giving rise to a chain reaction. The energy released is the product of the missing mass times the speed of light squared, according to Einstein's equation. Although the mass that disappears is small, the cost-effectiveness of the process is large, since the value of the speed of light is B.

The control of this process requires, first of all, to slow down the neutron velocity by using a substance called moderator, which can be heavy water, graphite, etc. average On the other hand, it is also necessary to reduce the number of fissions issue ; if in each fission a total of 2.5 neutrons are released, only one must be used for a new reaction. By means of so-called regulating or absorbing substances, part of the neutrons can be absorbed, so that the chain reaction can be controlled.

Sometimes, when a high-energy neutron collides with the nucleus of a heavy atom, fission does not occur, but the neutron is absorbed in the nucleus, and capture occurs. In these capture reactions, radiation is emitted. The importance of capture reactions in nuclear reactors lies in the fact that from a non-fissile material - such as uranium 238 - new fissile compounds - plutonium 239 - are produced.

Fusion reaction: From the point of view of obtaining energy, the fusion reaction is much more profitable, since at the end of the reaction there are fewer atoms than at the beginning. The simplest case could be represented by the fusion of two deuterium atoms, an isotope of hydrogen, resulting in a He atom and a neutron, according to the equation:

H21 + H21 =He32 + H10 + energy

An enormous amount of energy is released in this fusion reaction and is reasonably thought to represent an inexhaustible source , since deuterium can be obtained in unlimited quantities from seawater. This is the reaction that takes place in the Sun, supplying energy to the entire solar system.

It is, however, a very difficult reaction to achieve on internship, because not only are very high temperatures - about five million Degrees- needed to achieve the right speed of the atoms, but it is also still uncontrollable.

Nuclear reactors - A nuclear reactor consists essentially of an active core, formed by the fuel, where energy is released in the form of heat; this heat is used to generate steam, which is used to drive turbines. Reactor fuel consists essentially of fissile material, such as uranium-233, uranium-235 and plutonium-239. Of these, only uranium-235 exists in nature as part of natural uranium. The other two are obtained artificially, by capture reactions.

Depending on the fuel used, there are three types of reactors: simple reactors, which use enriched uranium to produce heat energy. Converter reactors, which use the uranium 235 contained in natural uranium and, in addition, convert part of the uranium 238 into plutonium 239 for use by other reactors. Regeneration reactors generate fissile material from fertile material, and their 'ash' represents a larger amount of fuel than they received. These reactors require very powerful cooling, with liquid sodium or potassium; liquid sodium is dangerous as it ignites in open air and explodes when contact with water.

Radiation - Nuclear reactions produce radiation of various types: alpha radiation, positively charged, corresponding to helium nuclei; beta radiation, negatively charged, formed by disintegrating electrons; and gamma radiation, electromagnetic in nature.

Alpha particles and neutrons have a high ionisation capacity. They are the most likely to cause irreparable damage to cells, but they are also the easiest to contain, as a sheet of paper is sufficient to contain them. Beta particles, gamma radiation and X-rays, on the other hand, are radiation that transfers leave linear energy. They are less ionising but more penetrating and can cause damage to the body.

Risks of nuclear power plants

No human activity is safe from accidents, which are often the result of technical or human failures that are difficult to avoid. Until April 1986, when the Chernobyl accident occurred, commercial nuclear power development had not produced a single fatal accident in several decades. Safety rates were satisfactory compared to non-nuclear power, especially coal mining. In principle, the dangers of a power plant could be summarised in three: A serious reactor failure, with consequences impossible to predict, in which a variable proportion of the population could be subjected to very high radiation doses, including highly ionising radiation. The existence, in the vicinity of the reactor, of radiation with high penetrating power, and the radioactivity of the waste.

Reactor core meltdown. The most frightening aspect of a possible reactor failure is that of a reactor core meltdown, with potentially very serious consequences, albeit less serious than those of an atomic explosion. A few years ago, the US Nuclear Energy Commission commissioned Norman C. Rasmussen, a professor of nuclear engineering in Massachusetts, to conduct a report study on the safety of light water nuclear reactors. Rasmussen assembled a team of 60 people, who produced a meticulous project called report Rasmussen, according to which the risk of a serious failure was estimated at a 20,000 reactor-year probability. They also made it clear that a core meltdown would not pose a threat to the population. They pointed out that the chance of a normal citizen dying as a result of a reactor accident would be about the same as being killed by a meteorite. Rasmussen's report triggered a storm of criticism, given the emotional climate in which it was received, so the Nuclear Regulatory Commission (NRC) commissioned a new report by a commission chaired by Harold W. Lewis, which found major flaws in Rasmussen's report , but generally considered the analysis to be valid. They found that the uncertainty Degree was much higher than that in report Rasmussen, but could not say whether the probability of a severe accident was higher or lower.

According to data , six fatal errors - human mistakes - caused the Chernobyl catastrophe when one of the reactors caught fire. "The collective dose of radioactivity in the inhabitants of the regions of the Soviet Union affected by the Chernobyl cloud was estimated at 8.6 million rem per person in 1986 and 29 million rem per person over the next 50 years, due to external radiation; 210 million rem per person over the next 50 years will come from internal radiation, either by inhalation or in the food chain. According to estimates, which are not generally agreed, these doses will cause 40,000 cases of cancer over the next 70 years, with varying incidences from one area to another; for the 135,000 evacuees, this incidence will be 20 to 30 times higher than for the others. In the rest of the world, over the same period, 20,000 tumours will be associated with the radioactive cloud"2.

Radiation emitted. The radiation emitted by a nuclear power plant into the environment involves a minimal risk. The following table shows the radiation that can be received by an organism, including that attributable to a nearby nuclear power plant.

Radiation in the vicinity of the nuclear power plant

(Comparison with others)

 

Per hour of exhibition

Per year
(8 h/day, 220 days)

Per year (24 h/day, 330 days)
(24 h/day, 330 days)

Next to central

0.2 mrem

352 mrem

--

2 kms away

0,02 "

3,5 "

158 mrem

10 kms away

0,002 "

3,5 "

15,8 "

 

 

 

 

 


Cosmic radiation: 100 mrem

Food and air: 25 mrem

Colour TV (2 h/day): 100 mrem

1 chest x-ray: 100 mrem

1 gastro-intestinal X-ray: 500 mrem

Radiotherapy treatment of cancer: 5000 rem

In the extreme case of being next to the plant, 0.2 mrem per hour would be received. Assuming a worker who spends 8 hours a day for 220 days, he would receive 352 mrem, which at 2 km from the plant would become 35.2 mrem and at 10 km 3.5 mrem. Even an inhabitant living 10 km from the power station and spending 360 days a year at home would receive about 17 mrem, an amount surpassed by the simplest X-ray or colour TV.

As is well known, injury from ionising radiation is most noticeable in what we call labile tissues, or rather, tissues containing labile cells. There are essentially four zones containing labile cells, on whose proliferation tissue regeneration depends, so that when the possibility of reproduction of labile cells - stem cells - is lost, the integrity of the tissue is lost, in a time that varies with the speed of cellular turnover. These areas are the labile undifferentiated cells present in the neck of the villous crypts, which give rise to the epithelium lining the intestinal villi; the stem cells in the bone marrow and lymphoid organs, whose proliferation gives rise to the blood cell population.

The epidermis also maintains a continuous renewal of cells, which originate in the stratum basale or germinative layer - labile cells - and are shed in the stratum corneum. Germ cells are equally labile and can be affected by radiation; chromosomal alterations can occur, which, when not lethal to the cell, can be transmitted to offspring.

The atomic bombs dropped on Hiroshima and Nagasaki have, unfortunately, provided information on the effects of mass radiation; the results are superimposable on those obtained in animal experiments. The dose-related effects can be summarised as follows: at 25,000 mrem, there are no clinical effects. They are only detected under special analysis. At 50,000 mrem, small changes in blood composition occur. At 300,000 mrem, nausea, vomiting and death occur in 20% of cases, while the rest recover. At 600,000 mrem, death is virtually certain. In cases of chronic radiation the effects are not predictable and these alterations have been studied on the basis of exposures for professional reasons (e.g. radiologists) and for medical treatments. The most important alterations of chronic radiation are the development of tumours and genetic alterations in offspring.

Finally, the most questionable aspect is that of waste treatment. At present, the best solution is to bury the waste at great depth.

On the other hand, the canisters must be buried widely, in order to dissipate the heat generated by the radioactivity. The heat generated decreases with time, so that if a container is buried after one year it would produce 1,900°C, whereas after 10 years it would produce only 250°C. The hazard of the waste is due to gamma radiation, the effect of which is attenuated by a factor of 10 when it passes through a thickness of 30 cm of soil. Therefore, the hazard virtually disappears with deep burial, unless the waste is accidentally dug up at a later date.

Because of the serious consequences of a nuclear reactor breakdown, or of uncontrolled radiation, a high level of safety cover has been required and developed from the outset. This is the first unavoidable aspect: the objective evaluation of possible risks and the appropriate measures to eliminate them are absolutely ethical requirements, over and above economic evaluations or political interests. But the guarantees of adequate safety measures are not in themselves sufficient to be able to conclude that the problem of the use of this energy source - cheap and less limited than those used so far - has been solved. According to agreement with Schumacher3 , to say that "scientists and technicians of the future will be able to create standards and precautions of such safety perfection that the use, transport, processing and storage of ever-increasing quantities of radioactive materials will be entirely safe... is, again, an attempt to solve a problem by sending it to another sphere, in this case to the sphere of man's behaviour".

The processes triggered to obtain this energy are new on earth, and their large-scale use today, when the problem of waste is still unresolved, implies a certain "mortgaging" of nature. It is true that anti-nuclear campaigns are often manipulated by political interests, and even that they are under strong psychological pressure from the peaceful use of an energy originally developed for war purposes, etc., but there is a valid argument at their base: the concern that an energy-intensive process is being introduced which is not part of the naturally balanced elements of the earth. We must have confidence in safety measures to ensure that the process is not lost control of, but we are not sure that the waste from a massive use of atomic fission processes as a solution to the energy problem is within nature's margin of tolerance. David, former President Nixon's science advisor, graphically referred to the topic waste storage in these terms: "it makes one nauseous to think that something must remain buried and well sealed for 25,000 years before it is harmless".4 Coal-fired power plants also dump waste, some of it highly toxic, but it is "terrestrial".

At final, the proposal of replacing billions of tonnes of fossil fuels with energy derived from fission - and later from atomic fusion - means that, in order to solve the problem created by the scarcity of a non-renewable resource , a greater environmental and ecological problem is created. It is therefore necessary not only to be sure of controlling the risks, but also to keep the rate of its production below the margins of "nature's tolerance", by first resolving the difficult topic of waste. Nature was not made by man and therefore, for its use, the criteria of utility, and even less so of immediate utility, are not sufficient, they are insufficient. From an ethical point of view, it is not enough to strike a balance between risks and benefits. There is an inescapable responsibility in initiating processes in which - like this one - it is not possible to take into account all side effects. Then, as Spaemann5 points out, the moral criterion can be expressed in the old maxim "nothing in excess". Even if the economic profitability is lower, the use of this energy power should find its own limits in smaller reactors, which are therefore safer in themselves, and in a reduced proliferation that allows nature to "metabolise" the radioactive waste. It is challenge in the technological mindset to channel nuclear potential into new strategies6 which, without eliminating the possibilities it offers, know how to find a balance, expressed in the ethical criterion we mentioned earlier: "nothing in excess".

(c) Orientations in the search for a solution to the energy crisis

The scientific and technological attempt to prepare alternative sources of energy to replace the current, almost exclusive use of non-renewable fuel must take into account these three coordinates: human subsistence, the current use of fossil fuels, and the exploitation and conservation of nature.

Schumacher points out, in the work cited above, that one of the major errors of our time is to believe that the problem of production has been solved; By considering that man's relationship with nature is merely external and one of domination, he acts as if the goods of nature - in this case fossil fuels - were something to be spent "as if it were an income and not natural capital", without worrying about their conservation, and without worrying that in the search for consumer goods, unknown substances are produced in nature, which cannot be dealt with by decomposing or recycling them, given that they are not natural. The orientations of this great economist, an expert on the development of rural areas and concerned about the need for a profound reorientation of technology to put it at the service of man, focus on the essential aspect of achieving a better Education. A new way of life is needed in which, alongside the development of new production methods, there are new consumption patterns. It is very common and widespread not to give value to what man has not made; but only those who know that value is not synonymous with price and know that there are differences, Degrees of being of things and do not measure by exclusive criteria of utility, can make an ethical use of nature, and of what nature gives to man. As Schumacher points out, "it makes no sense to speak of the dignity of man without accepting that noblesse oblige"7.

It seems clear that, in the loss of concepts, of "superior" and "inferior", when they make reference letter to the place that man occupies in the cosmos, lies the root of the difficulty that so often arises in finding the correct orientation of applied biology and of the eternal controversies between manipulation and respect: either to venerate nature or to submit it to the service of man. The lifestyle of the technological society, impregnated with consumerism, calls for a more habitable world, a world that is more cooperative with the environment, more friendly with nature. But the love of nature proclaimed by these ecological movements lacks content: it is about preserving a natural environment from human interference, for contemplation and enjoyment, forgetting the "other" nature, rather less idyllic, which man has needed and needs to "subdue" for his survival, and to work it to obtain the necessary resources.

In this disdain for technology - which at final is what makes their way of life possible - as in the unbridled defence of a dominion that seeks exclusively exploitation at any price, there is the same lack of meaning: the failure to rediscover man's place in nature and man's place in his work.

As seen above, the ethics of the technological mastery of nature offers general principles that guide the actions of human science. Some proposed "ethical codes" contain concrete measures - guidelines - for the restoration, or preservation, of nature from harsh or aggressive technologies on a large scale. These are measures which, because of their nature and scope, must be taken by those who manage and plan, by the institutions concerned.

Notes

(1) DIVITT, J.F. "Information, an indispensable factor". UNESCO Courier, July, 1981, p. 19.

(2) RUBBIA, C. and CRESCENTI, N. "The nuclear dilemma". Spoting and Kupfer, 1987. Quoted in El País, 20,4,87.

(3) SCHUMACHER, E.F. "Small is beautiful". H. Blume Ediciones. Madrid, 1982, p. 18.

(4) DAVID. In "Small is beautiful". SCHUMACHER, E.F. H. Blume Ediciones. Madrid, 1982, pp. 18.

(5) SPAEMANN, R. "Los efectos secundarios como problema moral" in "Crítica de las utopías políticas". EUNSA. Pamplona, 1987.

(6) LESTER, R.K. "New Strategies for Nuclear Energy". research and Science, 132, 58-70.

(7) SCHUMACHER, E.F. "Small is beautiful". H. Blume Ediciones. Madrid, 1982, p. 96.

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