Calder Hall THE STORY OF BRITAIN'S FIRST ATOMIC POWER STATION by KennethAJay Atomic Energy Research Establishment Harwell HARCOURT, BRACE & CO INC NEW YORK e gl o o g d- p # e s u _ s s e c c a g/ or st. u hitr at h w. w w p:// htt d / e z giti di e- gl o o G n, ai m o D c bli u P T / M G 7 5 7: 0 3 2 1- 1 1- 1 0 2 n o d e at er n e G First published in 1956 Phoenix I K* 1377 •CIS J42 Library of Congress Catalog Card Number: 56-11939 PRINTED IN GREAT BRITAIN e gl o o g d- p # e s u _ s s e c c a g/ or st. u hitr at h w. w w p:// htt d / e z giti di e- gl o o G n, ai m o D c bli u P T / M G 7 5 7: 0 3 2 1- 1 1- 1 0 2 n o d e at er n e G FOREWORD by Sir Edwin Plowden, K.C.B., K.B.E. Chairman of the United Kingdom Atomic Energy Authority 01 17 October 1956 when Her Majesty The Queen officially opens Calder Hall Nuclear Power Station, electric power will flow into the national electricity grid. This will be a memorable day in the history of the United Kingdom Atomic Energy Authority and a remarkable event for this country and for the whole world. Industry depends on power. The revolutionary industrial developments of the last 200 years have been based primarily on the exploitation of coal as a source of power. To coal has been added—within little more than living memory—oil. In some parts of the world the force of flowing water has been used to generate electricity: but most of the world's power comes from the fossil fuels—coal and oil. Now a new fuel and a new source of power is put to the service of mankind. The fuel is uranium and the source of power is 'atomic energy'. Calder Hall will be the first large- scale plant in the world to produce electricity by using the heat developed by the fission of uranium in nuclear reactors. It will demonstrate not on paper, not by a laboratory or pilot model, but on an industrial scale that scientists and engineers have found ways of adding to the world's store of wealth a e new sourcgle of useful energy: a source with a potential large o enough too allow the great industrial systems to continue g hundredsd-—even thousands—of years beyond the time when p the sourc#es of power on which we have hitherto principally e relied wills have been exhausted. u This achies_vement would have been of particular importance s to the Unieted Kingdom even if the first station had not been a c c a g/ or st. u hitr at h w. w w p:// htt d / e z giti di e- gl o o G n, ai m o D c bli u P T / M G 7 5 7: 0 3 2 1- 1 1- 1 0 2 n o d e at er n e G iv CALDER HALL ATOMIC POWER STATION British one. Coal was the foundation of our rise to industrial pre-eminence in the nineteenth century, but it is becoming increasingly hard to win in the ever greater quantities required by our continuing industrial development. Oil is being used more and more extensively, but this country itself is poor in oil resources. The geography of this small and densely- populated island is such that water power does not, and cannot be expected to, meet more than a small fraction of our needs of power. Great Britain, therefore, stood more in need of some new source of power than countries which are larger or less densely populated or which have vast resources of fossil fuel still to exploit. The achievement is a British one, and this gives it an additional importance. It is a demonstration of what British skill can do and—over and above that—it has given the sort of incentive to advance in allied industrial fields that great technological achievements have always done. In the design ing and building of Calder Hall the Atomic Energy Authority have made a wide variety of unusual and exacting demands upon industry—for materials of unusual purity, for equipment of unprecedented complexity, and so on. These demands, all of which have been met, will have their effects on fields far removed from the generation of nuclear power and give the stimulus that is required if a country is to continue, e as this cogluntry must, among the industrial leaders of the o world.o g The proced-ss will continue. Calder Hall will be followed by p more pow#erful and more advanced stations. At first these e will be bassed on the same sort of reactor as there is at Calder u Hall. Lates_r other types of nuclear reactor will take their s places in ethe country's nuclear power programme. That pro c gramme wacill go on expanding. Within ten to fifteen years we may haveorg/ reached the point at which every new power station will be a nst.uclear power station. In the coming decades, there fore, the nuuclear power industry will make an increasing contributihitron to, and provide a continuing stimulus for, the at h w. w w p:// htt d / e z giti di e- gl o o G n, ai m o D c bli u P T / M G 7 5 7: 0 3 2 1- 1 1- 1 0 2 n o d e at er n e G FOREWORD V rest of British industry. The role of the Atomic Energy Authority in this will be to lead the way—to design, build and operate new types of reactor. As has already happened with Calder Hall, the lessons of the Authority's pioneering work will be passed on to enable industry to undertake the large-scale expansion that lies ahead. Atomic energy is news. It has been through the whole of its short history. For this very reason there is a danger that the really significant development may not stand out as it should from the many interesting but minor ones which catch the public eye. In any true perspective the opening of Calder Hall must bulk large, particularly for this country. Ten years ago this country had no organization for studying or exploit ing atomic energy in either its military or its civil applications. Throughout the ten years, moreover, there have been rival calls on the scientific and engineering manpower of the country and on our material resources to an extent never previously known in time of peace. In spite of all this the project which is now the Atomic Energy Authority has been built up until it numbers some 24,000 people. The men and women of the Authority, under the leadership of Sir John Cockcroft, Sir Christopher Hinton and Sir William Penney, and with the help of industry, have, besides all their contri butions to national strength and scientific advance, been the e first peopglle anywhere to harness atomic energy on an indus o trial scaleo to the service of us all. g d- p # e s u _ s s e c c a g/ or st. u hitr at h w. w w p:// htt d / e z giti di e- gl o o G n, ai m o D c bli u P T / M G 7 5 7: 0 3 2 1- 1 1- 1 0 2 n o d e at er n e G Contents FOREWORD BY SIR EDWIN PLOWDEN, K.C.B., K.B.E. page ill 1. POWER FROM THE ATOM: FIRST THOUGHTS 1 2. THE DESIGN IS CHOSEN: "PIPPA" 15 3. THE BUILDING OF "PIPPA" 38 4. REACTOR NO. I STARTS UP 63 5. ANSWERS FOR THE ENGINEERS: THE ROLE OF RESEARCH 69 6. NUCLEAR POWER: THE FUTURE 80 e gl o o g d- p # e s u _ s s e c c a g/ or st. u hitr at h w. w w p:// htt d / e z giti di e- gl o o G n, ai m o D c bli u P T / M G 7 5 7: 0 3 2 1- 1 1- 1 0 2 n o d e at er n e G Plates 1. Calder Hall: a general view facing page 8 2. Heat exchanger shell on plinth 9 3. Completed heat exchanger 24 4. Bottom dome of pressure vessel 25 5. Inlet manifold of pressure vessel between Thediagrid pages 32 and 33 6. A layer of the graphite core Laying the core 7. Cleaning boiler tubes for the heat exchanger 8. Placing the tubes in position 9. Header tubes for loading fuel elements between 10. The tubes in position P°Sa 48 and 49 11. The charge / discharge machinery 12. The fuel element 13. The turbine hall facing page 56 14. The reactor control room 57 The electrical control room 15. Heat exchanger shell 72 16. The electricity is fed into the'grid' 73 vii e gl o o g d- p # e s u _ s s e c c a g/ or st. u hitr at h w. w w p:// htt d / e z giti di e- gl o o G n, ai m o D c bli u P T / M G 7 5 7: 0 3 2 1- 1 1- 1 0 2 n o d e at er n e G e gl o o g d- p # e s u _ s s e c c a g/ or st. u hitr at h w. w w p:// htt d / e z giti di e- gl o o G n, ai m o D c bli u P T / M G 8 5 7: 0 3 2 1- 1 1- 1 0 2 n o d e at er n e G CHAPTER ONE Power from the Atom: First Thoughts In the autumn of 1956 atomic energy will for the first time contribute directly to Britain's sources of industrial power when the nuclear power station at Calder Hall, in Cumber land, begins to feed substantial amounts of electricity into the Central Electricity Authority's grid. The occasion will be a milestone in the industrial history not only of this country but also of the world. The USA and the USSR have previously demonstrated the possibilities of nuclear power by generating small quantities of electricity in experimental plants, and the USA has for some time had an operational submarine driven by atomic energy, but Great Britain's Calder Hall station will be the first to operate on a truly industrial scale. It is designed to generate some 90,000 kW of electrical power, and at the same time to manufacture plutonium, the artificial nuclear fuel, for military purposes. This book is a report on Calder Hall. Its purpose is to describe the chain of thoughts and events which led to the design chosen for this station, the early gropings and flashes of inspiration, the systematic study on paper and in the laboratory of the feasibility of various proposals, the emer gence of an engineering design, the construction with its concomitant development and research, and finally the possi bilities for the future of this type of plant and its place in e the Goverglnment's ten-year programme for industrial atomic o energy. Bout before going into these details we shall first g recapitulad-te the basic facts about the atom and the principles p underlyin#g atomic energy. e ATOMS ANsD NUCLEAR FUELS u An atom os_f matter is like an incredibly tiny solar system. s It has a ceentral sun, called the nucleus, round which move c 1 ac g/ or st. u hitr at h w. w w p:// htt d / e z giti di e- gl o o G n, ai m o D c bli u P T / M G 8 5 7: 0 3 2 1- 1 1- 1 0 2 n o d e at er n e G 2 CALDER HALL ATOMIC POWER STATION electrons, the planets of the system. The diameter of the nucleus is only about a ten-thousandth of that of the atom, yet in spite of its infinitesimally small size the nucleus is itself a complex body built up from particles called protons and neutrons, the ultimate building blocks of matter. Practically the whole mass of the atom is concentrated in the nucleus, for the mass of a planetary electron is less than a thousandth part of the mass of a proton or neutron. When matter undergoes a chemical reaction, such as burn ing for example, the planetary electrons of its atoms are rearranged and as a consequence energy is released. This energy appears generally as heat, as the heat of a coal fire, or light, as in a gas flame. In these reactions the nuclei of the atoms taking part are undisturbed. In some circumstances, however, it is possible to produce a reaction in which a nucleus is disturbed or even broken up, and when this is done very much more energy may be released than is possible when only the planetary electrons are involved. Unlike chemical reactions nuclear reactions cannot generally be made to spread from one atom to the next; each nucleus has to be treated individually. But there is one exception to this rule, the reaction called nuclear fission, which is the cornerstone of nuclear power. Fission is produced when a nucleus of certain elements is struck by a neutron; the nucleus absorbs the e neutron, iglts equilibrium is disturbed, and it is split into two o more or leoss equal parts. In this splitting, energy is released g and also md-ore than one fresh neutron (actually about p 2-5 neutro#ns per fission on the average); the latter are most e importants because they can cause further fissions in neigh u bouring as_toms and these in their turn release more neutrons s to cause yeet another generation of fissions, and so on. In this c way thereac is produced a self-sustaining chain reaction, a nuclear fiorg/re. There arest. many fuels in which an ordinary fire can burn— coal, oil, guas, wood, even metals—but only one naturally occurringhitr material will sustain a nuclear fire. That is the at h w. w w p:// htt d / e z giti di e- gl o o G n, ai m o D c bli u P T / M G 8 5 7: 0 3 2 1- 1 1- 1 0 2 n o d e at er n e G