IAEA-TECDOC-431 LOW-TEMPERATURE NUCLEAR HEAT APPLICATIONS: NUCLEAR POWER PLANTS FOR DISTRICT HEATING REPORT OF AN ADVISORY GROUP MEETING ON LOW-TEMPERATURE NUCLEAR HEAT APPLICATIONS: NUCLEAR POWER PLANT DISTRICR SFO T HEATING ORGANIZEE TH Y DB INTERNATIONAL ATOMIC ENERGY AGENCY AND HEL PRAGUEDN I , 23-27 JUNE 1986 A TECHNICAL DOCUMENT ISSUED BY THE INTERNATIONAL ATOMIC ENERGY AGENCY, VIENNA, 1987 LOW-TEMPERATURE NUCLEAR HEAT APPLICATIONS: NUCLEAR POWER PLANTS FOR DISTRICT HEATING IAEA, VIENNA, 1987 IAEA-TECDOC-431 Printed by the IAEA in Vienna August 1987 PLEASE BE AWARE THAT ALL OF THE MISSING PAGES IN THIS DOCUMENT WERE ORIGINALLY BLANK The IAEA does not normally maintain stocks of reports in this series. However, microfiche copie f thesso e reportobtainee b n sca d from IN IS Clearinghouse International Atomic Energy Agency Wagramerstrasse5 P.O. Box 100 A-1400 Vienna, Austria Orders shoul accompaniee db prepaymeny db f Austriao t n Schillings 100,- fore for e chequa th m f th IAEf m o n o i n i r eAo microfiche service coupons which may be ordered separately from the INIS Clearinghouse. FOREWORD Nuclear powe alreads lona ha r r g fo yperio d playe vera d y important productioe th rol n i e electricitf no durind an y g 4 nuclea198639 e th r, power plants in 26 countries, with 270 GW(e; total net capacity generated totae th lf nearl o electricit % 16 y y productio worlde th n .i n This production corresponds to about 560 million tonnes of equivalent coal. If the present growth is maintained and if there are no cancellations and no slow-dow implementatioe th n i n plannef no d projects worldwide th , e nuclear power capacity is expected to be around 370 GW(e) by 1990, with nuclear power contributin world'e th f o s % electricag20 l energy supply. Besides generating electricity, nuclear reactors can also supply heat as a primary energy for heating purposed and for industrial needs. Technical and economic studies in several countries have shown that the heat delivery from nuclear source mann i ys i scase s competitive with fossil-fuelled plantcontributins i d san e sam th e t th a timg o t e cleanlines environmente th f o s . Low-temperature nuclear heat gainea s a d co-product of electricity from nuclear power plants (co-generation)is used already in a number of countries for the supply of warm water or steam from very different type reactorf o svariout a d an ss capacities. Compared with nuclear co-generation plant e specializeth s d nuclear heating plants n earla arn i ye stag developmenf eo d Implementationtan . The IAEA reflected the needs of its Member States for the exchange of information in the field of nuclear heat application already in the late 1970s. In the early 1980s, some Member States showed their interest in f heao te th us efro m electricity producing nuclear powee th r n planti d an s developmen f nucleao t r heating plants. Accordingly a technica, l committee meeting wit workshoha organizes wa p 198n i d revieo 3t statue th w f so nuclear heat application which confirmed bot e progresth h s mad thin i e s field and the renewed interest of Member States in an active exchange of information about this subject. In 1985 an Advisory Group summarized the Potential of Low-Temperature Nuclear Heat Application; the relevant Technical Document reviewin situatioe gth e IAEA' th n si n Member States swa issued in 1986 (IAEA-ThCDOC-397). Programme plans were made for 1986-88 e IAEans asketh d Awa promoto t d exchange th e f informationo e , with specific emphasi desige th n no s criteria, operating experience, safety requirements and specifications for heat-only reactors, co-generation plant d powean s r plants adapte hear fo dt application. Becausa f eo growing interest of the IAEA's Member States about nuclear heat employment districe ith n t heating domaine n Advisora , y Group meetin s organizewa g d by the IAEA on "Low-Temperature Nuclear beat Application: Nuclear Power Plant Districr fo s t Heating Praguen "i , Czechoslovaki Junn i a e 1986e .Th information gained up to 1986 and discussed during this meeting is embodied in the present Technical Document. hopes Ii t d that this report would serv e IAEth eA Member Staten a s sa useful technico-economical informatiof o ne us abou e statue th th t f o s low-temperature nuclear heat and give ideas to those who are intending to employ this source of heat as substitution for fossil fuel. EDITORIAL NOTE preparingIn this materialpress, the International the stafffor of Atomic Energy Agency have mounted and paginated the original manuscripts and given some attention to presentation. The views expressed do not necessarily reflect those of the governments of the Member States or organizations under whose auspices manuscriptsthe were produced. thisin The bookuse of particular designations countriesof territoriesor does implynot any judgement by the publisher, the IAEA, as to the legal status of such countries or territories, of their authorities and institutions or of the delimitation of their boundaries. The mention of specific companies or of their products or brand names does not imply any endorsement recommendationor IAEA. partthe the of on CONTENTS 1. INTRODUCTION .......................................................................................7 . 2. HEAT SOURCES FOR DISTRICT HEATING ................................................... 8 2.1. General approach to the selection of heat sources for the DH 1. INTRODUCTION In 198s expectea 6- - dnuclea r power reactors worldwide have accumulated 4000 reactor year f operation o snuclea4 39 e rTh powe. r plants f countrie6 198o 2 (NPP d n 6n operatioI i en ) e sth wity GW(e0 b n 27 h ) capacity gav e world'th e f nearlo s% electriy16 c energy. For more tha year0 3 ne NPP e th playins ar s n Importana g e t th rol n i e safe and reliable generation of electricity. Public confidence, shaken by the Three Mile Island accident, was coming back and until spring 1986 some hesitating countries starte o decidt d n favoui e f nucleao r r powere Th . Chernobyl accident in late April 1986 changed again the situation rapidly: The situation differs from country to country and in some of them it may slow dow e developmenth n f nucleao t r power evey nn ma somi , leat i eo t d the deferring of nuclear programme. Before Chernobyl in the IAEA's calculations the forecasts for nuclear generating capacity was some 40O GW(e) aroun e yeath d r 1990, what should give mor f enucleao tha% 20 n r share in the world electricity generation total. It is conceivable that these figuree affectedb y ma s . Most countries with developed nuclear installations are, of course,l beyond the point of no return from the nuclear programme Directoe Th . r Genera e Internationath f o l l Atomic Energy Agency, Dr. U. Blix, stated in his speech on June 2nd 1986 at the 2. HEAT SOURCES FOR DISTRICT HEATING The heat needs in industrialized countries are rather high and as already mentioned above severan ,i thef lo m even more tha thire non f o d the fuel currently used is being consumed for heating houses and for supplying industry with process heat. Should these amount fossif so l fuel savee sb y replacinb d g them with nuclear generated heat coult ,i ) d(a bring high savings in the countries' fuel economy, (b) save these products as valuable chemical raws and (c) contribute to the cleanliness of the environment. In the USSR, where large demands for heat occur, the production of watet stead fore ho ran th heaf mo mn i tconsume 198n i d O more tha0 60 n million tons of equivalent fuel. It is therefore not surprising that this large country with high heat needs startede th alread e us o yt lono gag nuclear substituta hea s ta fossir efo lconstantls i fuel d san y payinn a g even increasing attention to this way of heat provision. They are, however, much smaller countries with a similar policy: as an example Switzerland can be introduced, where according to the " Bundesamt fuer Energiewirtschaft" studies were made confirming the advantage of nuclear heat application substitutin fossir fo g l fuel wit gooha d efficiencd yan economy and with a substantial contribution to the improvement of the envi ronment. The heat policy of each individual country is usually a complicated tass alreadkwa t andi y s e IAE,a showth A n nTECOÛC-397i waye ,heaf th s o t provision are very much "country-specific". When a decision is taken to build up centralized district heating systems (CDHS), not only the corresponding heat sources are to be developed but all other parts of the systems have to be implemented as well, such as heat feeding network, heat exchanger stations etc. Only in a few countries with a long tradition of existing CDHS conditions were so positive that further development of larger CLHS became a logical step in the medium and long-term prospective plans. In several other case developmene sth CDHf to s foun costlo Swa to dd therefor an y e several compromises were accepted in some countries (.outlooking, of course, from political constraints publie ,th c attitude etc.;. Some general views featurin e philosophth g selectioe th e f th o y f no most suitable technology servin s futurga e heat sourc districr fo e t heating (Drij syste e introducemar e followinth n i d g sub-chapter.