energy 0901

8/13/2019 Energy 0901

1/104

Karasalihovi Sedlar, D., Dekani, I., Hrnevi, L., Sigurnost opskrbe naftom , Energija, god. 58(2009 ), br. 1., str. 6-13Karasalihovi Sedlar, D., Dekani, I., Hrnevi, L., Oil Supply Security , Energija, vol. 58(2009 ), No. 1, pp. 6-131

8/13/2019 Energy 0901

2/104

Karasalihovi Sedlar, D., Dekani, I., Hrnevi, L., Sigurnost opskrbe naftom , Energija, god. 58(2009 ), br. 1., str. 6-13Karasalihovi Sedlar, D., Dekani, I., Hrnevi, L., Oil Supply Security , Energija, vol. 58(2009 ), No. 1, pp. 6-13 2

ENERGIJAENERGIJA

CONTENTSSADRAJ

01/09IZDAVAHrvatska elektroprivreda d.d., Zagreb

SUIZDAVAISveuilite u Zagrebu, Fakultet elektrotehnike i raunarstvaMinistarstvo gospodarstva, rada i poduzetnitva

ZA IZDAVAA

Mr. sc. Ivan MravakPOMO U IZDAVANJUMinistarstvo znanosti, obrazovanja i porta

UREIVAKI SAVJETMr. sc. Kaimir Vranki,(predsjednik), Zagreb doc. dr. sc.Ante urkovi, Zagreb prof. dr. sc. Igor Dekani, Zagreb prof. dr. sc. Danilo Fereti, Zagreb - mr. sc. Nikica Grubii,Zagreb prof. dr. sc. Slavko Krajcar, Zagreb doc. dr. sc.eljko Tomi, Zagreb doc. dr. sc. Mladen Zeljko, Zagreb

UREIVAKI ODBORGlavni urednik Mr. sc. Goran Slipac, ZagrebGlavni tajnik Mr. sc. Slavica BartaKotrun, ZagrebLektor imun agalj, prof., ZagrebMetroloka recenzija Dragan Borojevi, dipl. ing., ZagrebPrijevod Hrvatsko drutvo znanstvenih i tehnikih pre-voditelja Prevoditeljski centar, ZagrebUREDNITVO I UPRAVAHEP d.d. EnergijaUlica grada Vukovara 37, 10000 Zagreb, HrvatskaTelefoni: +385(1) 6171291 i 6322641Telefaks: +385(1) 6322143e-mail: [email protected]; [email protected]

Godinje izlazi 6 brojevaGodinja pretplata bez PDV-a(10 %) iznosi: za pojednice 275 kn za poduzea 440 kn za studente 65 kniro raun kod Zagrebake banke broj:2360000-1400129978

Godinja pretplata za inozemstvo iznosi USD 95.Devizni raun:Zagrebaka banka broj: 2000006299

Gra ko ureenje omota mr. sc. Kaimir Vranki, ZagrebGra ko ureivanje Bestias dizajn. d.o.o., ZagrebTisak Tiskara Zelina d.d., Sv. Ivan Zelina

Naklada 1 500 primjerakaGodite 58(2009)Zagreb, 2009Broj 1., str.1-104

Oglasi su veliine jedne stranice. Cijena oglasa je 3 000 knbez PDV(22 %).

PUBLISHED BYHrvatska elektroprivreda d.d., Zagreb

CO-PUBLISHED BYUniversity of Zagreb, Fakulty of Electrical Engineering and Com-puting Ministry of Economy, Labour and Entrepreneurship

PUBLISHERS REPRESENTATIVEIvan Mravak, MSc

SUPPORTED BYMinistry of Science, Education and Sport

EDITORIAL COUNCILKaimir Vranki, MSc,(Chairman), Zagreb Assistant Prof Anteurkovi, PhD, Zagreb Prof Igor Dekani, PhD, Zagreb ProfDanilo Fereti, PhD, Zagreb Nikica Grubii, MSc, Zagreb Prof Slavko Krajcar, PhD, Zagreb Assistant Prof eljko Tomi,PhD, Zagreb Assistant Prof Mladen Zeljko, PhD, Zagreb

EDITORIAL BOARDEditor-in-chief Goran Slipac, MSC, ZagrebSecretary - Slavica BartaKotrun, MSc, ZagrebLanguage Editor imun agalj, prof., ZagrebMetrology Dragan Borojevi, dipl. ing., ZagrebTranslation Croatian Association of Scientific and TechnicalTranslators Croatian Translation Agency, ZagrebHEAD OFFICE AND MANAGEMENTHEP d.d. EnergijaUlica grada Vukovara 37, 10000 Zagreb, HrvatskaTelephone: +385(1) 6171291 and 6322641Fax: +385(1) 6322143email: [email protected]; [email protected]

Appears 6 times a year.Annual subsription fee excl. VAT(10 %): for individual subscribers HRK 275 for companies HRK 440 for students HRK 65Number of fgyro account whit Zagrebaka Banka:23600001400129978

Annual subscription fee for the overseas: USD 95.Number of foreign currency account whit Zagrebaka Banka:2000006299

Cover design Kaimir vranki, MSc, ZagrebGraphic layout Bestias Dizajn d.o.o., ZagrebPrinted by Tiskara Zelina d.d., Sv. Ivan Zelina

Circulation 1 500 copiesVolume 58(2009)Zagreb, 2009No. 1., p. p. 1-104

Ads are the size of the page. The price of an ad is HRK 3 000excl. VAT(22 %).

Karasalihovi Sedlar, D., Dekani, I., Hrnevi, L.SIGURNOST OPSKRBE NAFTOM U HRVATSKOJ(pregledni lanak)

Grubii, N.DUGORONI IZGLED CIJENA NAFTE I PLINA(prethodno priopenje)

Klepo, M., Mikulii, V., imi, Z.MODEL PROIZVODNE JEDINICE S UKLJUENIM UVJETIMAOKOLINE U MODELU POUZDANOSTI I RASPOLOIVOSTIELEKTROENEGETSKOG SUSTAVA(prethodno priopenje) Hederi, ., Baruki, M., Mikloevi, K.ANALITIKI PRORAUN OSOVINSKIH STRUJA KOD MO-TORA S HOMOGENIM JARMOM(izvorni znanstveni lanak)

kare, J., Mesi, M.ZATITNI UREAJI I SELEKTIVNOST U PODSUSTAVIMAISTOSMJERNOG RAZVODA I NAPAJANJA

(struni lanak)asopis je ubiljeen u Ministarstvu znanosti, obrazovanja iporta pod brojem 161 od 12.11.1992.

asopis je indeksiran u sekundarnom bibliografaskom izvoruINSPEC The Institution of Electrical Engineering, England.

Karasalihovi Sedlar, D., Dekani, I., Hrnevi, L.OIL SUPPLY SECURITY IN CROATIA(review paper)

Grubii, N.LONG-TERM PROSPECT OF OIL AND GAS PRICES (preliminary information)

Klepo, M., Mikulii, V., imi, Z.PRODUCTION UNIT MODEL WITH ENVIRONMENTAL CONDI-TIONS INCLUDED IN THE ELECTRO-ENERGETIC SYSTEMRELIABILITY AND AVAILABILITY MODEL (preliminary information)

Hederi, ., Baruki, M., Mikloevi, K.ANALYTICAL CALCULATION OF SHAFT CURRENTS IN THE MO-TORS WITH HOMOGENEOUS YOKE (original scienti c paper)

kare, J., Mesi, M.PROTECTION DEVICES AND SELECTIVITY IN DC POWER DIS-TRIBUTION SUB-SYSTEMS

(professional article)The journal is registered with the Ministry of Science, Educationand Sport under No. 161 since 12.11.1992

The journal is indexed with the secondary reference source ofINSPEC The Institution of Electrical Engineering, England.

006-013

014-025

026-055

056-075

075-097

8/13/2019 Energy 0901

3/104

3

UREIVAKA POLITIKAasopis Energija znanstveni je i struni asopiss dugom tradicijom vie od 50 godina. Pokrivapodruje elektroprivredne djelatnosti i energet-ike. asopis Energija objavljuje izvorne znanst-vene i strune lanke irokoga podruja interesa,od speci nih tehnikih problema do globalnihanaliza procesa u podruju energetike.

U vrlo irokom spektru tema vezanih za funk-cioniranje elektroprivredne djelatnosti i openitoenergetike u trinim uvjetima i opoj global-izaciji, asopis ima poseban interes za speci neokolnosti ostvarivanja tih procesa u Hrvatskoj injezinu regionalnom okruenju. Funkcioniranjei razvoj elektroenergetskih sustava u sredinjoj i jugoistonoj Europi, a posljedino i u Hrvatskoj,optereeno je mnogobrojnim tehniko-tehnolokim, ekonomskim, pravnim i orga-nizacijskim problemima. Namjera je asopisa dapostane znanstvena i struna tribina na kojoj ese kritiki i konstruktivno elaborirati navedenaproblematika i ponuditi rjeenja.

asopis je posebno zainteresiran za sljedeutematiku: opa energetika, tehnologije za proiz-vodnju elektrine energije, obnovljivi izvori i zatitaokolia; koritenje i razvoj energetske opremei sustava; funkcioniranje elektroenergetskogasustava u trinim uvjetima poslovanja; izgrad-nja elektroenergetskih objekata i postrojenja;informacijski sustavi i telekomunikacije; restruk-turiranje i privatizacija, reinenjering poslovnihprocesa; trgovanje i opskrba elektrinom en-ergijom, odnosi s kupcima; upravljanje znanjemi obrazovanje; europska i regionalna regulativa,inicijative i suradnja.

Stranice asopisa podjednako su otvorene iskus-nim i mladim autorima, te autorima iz Hrvatskei inozemstva. Takva zastupljenost autora osigu-rava znanje i mudrost, inventivnost i hrabrost, tepluralizam ideja koje e itatelji asopisa, vje-rujemo, cijeniti i znati dobro iskoristiti u svojemprofesionalnom radu.

EDITORIAL POLICYThe journal Energy is a scienti c and profession-al journal with more than a 50-year tradition.Covering the areas of the electricity industryand energy sector, the journal Energy publishesoriginal scienti c and professional articles witha wide area of interests, from speci c technicalproblems to global analyses of processes in theenergy sector.

Among the very broad range of topics relatingto the functioning of the electricity industry andthe energy sector in general in a competitiveand globalizing environment, the Journal hasspecial interest in the speci c circumstancesin which these processes unfold in Croatia andthe region. The functioning and development ofelectricity systems in Central and South EastEurope, consequently in Croatia too, is bur-dened with numerous engineering, economic,legal and organizational problems. The inten-tion of the Journal is to become a scienti c andprofessional forum where these problems willbe critically and constructively elaborated andwhere solutions will be offered.

The Journal is especially interested in the fol-lowing topics: energy sector in general, elec-tricity production technologies, renewablesources and environmental protection; use anddevelopment of energy equipment and systems;functioning of the electricity system in competi-tive market conditions; construction of electricpower facilities and plants; information systemsand telecommunications; restructuring andprivatization, re-engineering of business pro-cesses; electricity trade and supply, customerrelations, knowledge management and train-ing; European and regional legislation, initia-tives and cooperation.

The pages of the Journal are equally open toexperienced and young authors, from Croatiaand abroad. Such representation of authorsprovides knowledge and wisdom, inventivenessand courage as well as pluralism of ideas whichwe believe the readers of the Journal will appre-ciate and know how to put to good use in theirprofessional work.

8/13/2019 Energy 0901

4/104

UVODINTRODUCTION

4

Dear Readers!

Before you is the rst issue of Energija for the year 2009. Thisyear began with a recession in the supply of natural gas, pri-marily to the countries of west and southeast Europe. This re-cession had severe repercussions on the countries which im-port all, or nearly all, necessary quantities of natural gas, andsomewhat lesser repercussions on the countries which availof certain amounts of reserves. In the last issue of Energija,we published an article which addressed natural gas supplysecurity in Croatia. In this issue, we continue with the analysisof oil supply security in Croatia, as well as with other aspects,such as long-term prospects of oil and natural gas prices. Wehope these articles will help you understand the events on theworld energy sources market, as well as the consequencesthese events can have on the supply of energy sources of thecountries such as, for example, Croatia.

In this issue of Energija we publish very interesting articlesfrom various elds, from energetic to specialist elds of elec-trical engineering:

Oil supply security in Croatia, Long-term aspects of oil and natural gas prices, Production unit model with environmental conditions

included in the electric power system reliability andavailability model,

Analytical calculation of shaft currents in homogenousyoke motors,

Protection devices and selectivity in DC power distributionsub-systems.

The rst article describes the concept of oil supply security inCroatia. Starting from the fact that Croatia settles its require-ments for primary energy sources from liquid and gas fuels atthe level of approximately 70 %, and that the share of import ofthese forms of energy will grow in the future, the authors es-tablish the need to create infrastructural assumptions for cre-ating strategic oil reserves. The estimate of necessary storagecapacities is made based on the projection of oil consumptionuctuations in Croatia, projection of oil production in Croatiaand on import. The projections of production, import and of oiland oil derivatives consumption in Croatia for the period until2020 are taken over from the latest projections of oil require-ments de ned in the draft of the Green Book of the Energy De-velopment Strategy of the Republic of Croatia.

In this issue we have another article which addresses oil andnatural gas market aspects. Namely, the issue of being famil-iar with future uctuations of the prices of these energy sourceshas been attractive. The speci city of this article lies in the factthat the future long-term oil and natural gas prices prospectsare analysed through the capital market and not through theusual complex econometric models. The author points out thatthe consideration of future oil and natural gas prices requiresdistinguishing short-term from long-term disturbances, thatis, determination factors. What is interesting is that as early asin the rst half of the year 2008, this author predicted a fall in

Potovani itatelji!

Pred Vama je prvi broj asopisa Energija u 2009. godini.Ova je godina poela redukcijom u isporuci prirodnog plina,ponajprije zemljama srednje i jugoistone Europe, koja jeteko pogodila zemlje koje uvoze sve ili gotovo sve potrebnekoliine prirodnog plina, a neto manje pogodila je zemljekoje su raspolagale odreenim zalihama. U prolom brojuasopisa Energija objavili smo lanak koji se odnosio naanalizu sigurnosti opskrbe prirodnim plinom u Hrvatskoj. Uovom broju nastavljamo s analizom sigurnosti opskrbe naf-tom u Hrvatskoj kao i drugim vanim aspektima, kao to suprimjerice dugoroni izgled cijene nafte i prirodnog plina.Nadamo se kako e vam ovi lanci pomoi u razumijevanjuzbivanja na tritu energenata kao i razumijevanja posljedica

koje mogu imati na opskrbu energentima zemalja, kao to jeprimjerice Hrvatska.

U ovom broju asopisa Energija objavljujemo vrlo zanimljivelanke iz razliitih podruja, od energetskih do specijalistikihpodruja elektrotehnike:

Sigurnost opskrbe naftom u Hrvatskoj, Dugoroni izgled cijena nafte i plina, Model proizvodne jedinice s ukljuenim uvjetima okoline

u modelu pouzdanosti i raspoloivosti elektroenergetskogsustava,

Analitiki proraun osovinskih struja kod motora s

homogenim jarmom, Zatitni ureaji i selektivnost u podsustavima istosmjernograzvoda i napajanja.

U prvom lanku opisana je koncepcija sigurnosti opskrbenaftom u Hrvatskoj. Polazei od injenice kako Hrvatskapodmiruje potrebe u primarnim oblicima energije iz tekuihi plinovitih goriva na razini od priblino 70 % te kako e udiouvoza ovih oblika energije u budunosti rasti, autori de nirajupotrebu stvaranja infrastrukturnih pretpostavki za formiranjestratekih zaliha nafte. Prosudba potrebnih skladinih kapac-iteta izvrena je temeljem projekcije kretanja potronje nafteu Hrvatskoj, projekciju proizvodnje nafte u Hrvatskoj te uvoza.Projekcije proizvodnje, uvoza kao i potronje nafte i naftnihderivata u Hrvatskoj za razdoblje do 2020. godine preuzete suiz najnovijih projekcija potreba za energijom de niranih u na-crtu Zelene knjige Strategije energetskog razvitka RepublikeHrvatske.

U ovom broju imamo jo jedan lanak koji se bavi aspek-tima trita nafte i prirodnog plina. Naime, pitanje spoznajebudueg kretanja cijena ovih energenata oduvijek je privlailapozornost. Speci nost ovog lanka je u tomu to se buduidugoroni izgled cijena nafte i prirodnog plina analizira kroztrite kapitala, a ne kako je to uobiajeno kroz sloeneekonometrijske modele. Autor u lanku istie kako je zasagledavanje budueg kretanja cijena nafte i prirodnog plinanuno luiti kratkorone poremeaje od dugoronih, odnosno

8/13/2019 Energy 0901

5/104

8/13/2019 Energy 0901

6/104

6Karasalihovi Sedlar, D., Dekani, I., Hrnevi, L., Sigurnost opskrbe naftom , Energija, god. 58(2009 ), br. 1., str. 6-13Karasalihovi Sedlar, D., Dekani, I., Hrnevi, L., Oil Supply Security , Energija, vol. 58(2009 ), No. 1, pp. 6-13

SIGURNOST OPSKRBENAFTOM U HRVATSKOJ

OIL SUPPLY SECURITY INCROATIADaria Karasalihovi Sedlar Igor Dekani Lidia Hrnevi,

Zagreb, HrvatskaZbivanja na globalnom energetskom tritu, porast trine nestabilnosti i sve

vea uloga geopolitike u opskrbi energijom, kontinuirano utjeu na energetskusigurnost koja predstavlja glavni postulat energetske politike, ali ujedno i

kriterij njezine uspjenosti. Osiguranje nesmetane opskrbe naftom i plinomosnovna je zadaa svake nacionalne energetske politike. Mogunosti i uvjeti

dobave primarnih izvora energije, meu kojima su nafta i prirodni plin dalekonajvaniji energenti s obzirom na njihov udio u potronji energije, te s obziromna njihovu strateku vanost, predstavljaju temelj za osiguravanje sigurnosti

opskrbe naftom i prirodnim plinom u sklopu nacionalne energetike. Sigurnostopskrbe naftom u Hrvatskoj je usmjerena na utvrivanje kritine energetskeinfrastrukture sa stajalita energetske sigurnosti, zatim na kreiranje sustava

za kontinuirano analiziranje i praenje sigurnosti opskrbe naftom, reagiranje usluajevima kritine opskrbe te razradu mjera za sprjeavanje i amortizaciju u

situacijama ugroenosti energetske sigurnosti.The occurrences on the global energy market, increased market instability

and the increasingly signi cant role of geopolitics in energy supply, continuallyimpact the energy supply security which represents the main postulate of

the energy politics, as well as a criterion of its successfulness. Assurance ofan uninterrupted oil and gas supply is the basic task of each national energypolicy. Possibilities and conditions of the supply of primary energy sources,

among which oil and natural gas are by far the most important energy sourcesin relation to their share in energy consumption, and as regards their strategic

importance, these represent the basis for assurance of oil and natural gassupply security within the national energy supply. Oil supply security in Croatia isdirected towards determining the critical energy supply infrastructure from theviewpoint of energy supply security, towards creating a system for continued oilsupply security analysis and monitoring, acting in critical supply situations and

towards an elaboration of measures for prevention and amortization in cases ofendangerment of energy supply security.

Kljune rijei: energetska sigurnost; sigurnost opskrbe naftom;strateke zalihe nafte

Key words: energy supply security; oil supply security; strategic oil reserves

8/13/2019 Energy 0901

7/104

8/13/2019 Energy 0901

8/104


1 UVOD

Analiza geopolitikih prilika na meunarodnimenergetskim tritima, procjena opasnosti odporemeaja opskrbe naftom i prirodnim pli-nom te predvianja sustava za ublaavanje po-sljedica u sluaju poremeaja opskrbe naftom,predstavlja znaajan element, kako energetske,tako i ukupne nacionalne sigurnosti [1]. Stoga je analiza sigurnosti opskrbe naftom u RH traj-na potreba energetske sigurnosti i nacionalnesigurnosti zemlje. S obzirom na injenicu daHrvatska oko 70 % svojih potreba u primarnojenergiji podmiruje koritenjem tekuih i plino-vitih goriva, odnosno nafte i plina, iznimno jevano ralanjivanje potreba, okolnosti i stanjadobave nafte.

2 ANALIZA STANJA UHRVATSKOJ S CILJEMUTVRIVANJA KRITINIHELEMENATA U OPSKRBINAFTOM

Kao ulazna pretpostavka analize stanja dugo-rono se predvia prosjena godinja stopa po-rasta domaeg proizvoda od 4,5 % godinje do2020. godine i ista dugorona dinamika rasta do2030. godine. S obzirom da su rast bruto doma-eg proizvoda, te proizvodnja i potronja ener-

gije uzajamno povezani, rast bruto domaegproizvoda zahtijeva i poveanje potronje ener-gije [2]. Potronja tekuih goriva u Hrvatskojpredstavlja glavni izvor energije u naoj zemlji.S obzirom na geografske znaajke Hrvatske kaoi gospodarsku vanost prometa i turizma za bu-dui razvitak, procjenjuje se kako e uloga teku-ih goriva u energetskoj potronji u Hrvatskoj idalje biti vrlo znaajna te da se njihov udio neeznatnije smanjivati u iduem razdoblju do 2020.godine, pa i do 2030. godine. Oekuje se da eizmeu 2020. i 2030. godine udio tekuih gorivau strukturi potronje neto pasti [3]. Prema podlogama za izradu Strategije energet-skog razvitka Hrvatske, u osnovnom scenarijukoji ukljuuje podrobnu analizu nalne potro-nje energije u industriji, prometu i opoj potro-nji, predvia se porast potronje tekuih gorivau neposrednoj potronji od oko 2 % godinje urazdoblju do 2030. godine i na temelju toga sepredvia potronja nafte koja je prikazana utablici 1 i na slici 1 [4]. Osim toga, procjena jeuzela u obzir i dodatne pretpostavke za procjenupotronje(gospodarski rast, smanjenje gubita-ka u preradi nafte, zamjenu goriva pri obnovira nerija, prestanak rada termoelektrana naloivo ulje, osiguravanje dodatnih koliina nafte

1 INTRODUCTION

Analysis of geopolitical circumstances on the inter-national energy markets, evaluation of the danger ofdisruption of oil and natural gas supply and the pla-nning of systems for amelioration of consequencesin case of oil supply disruption, represent signi cantelements both of the energetic and the overall na-tional security. Therefore, the analysis of oil supplysecurity in Croatia is a constant requirement of theenergy supply security and the countrys national se-curity. Considering the fact that Croatia settles about70 % of its needs of primary energy by using liquidand gaseous fuels, that is, oil and gas, it is extremelyimportant to analyse the requirements, circumstan-ces and situation in oil supply.

2 ANALYSIS OF THE SITUATION

IN CROATIA WITH THE AIM TODETERMINE CRITICAL OIL SUP-PLY ELEMENTSAs the input assumption of situation analysis, in thelong-term an average annual growth rate of dome-stic product is predicted at 4,5 % annually until year2020, and the same long-term growth dynamics arepredicted until year 2030. Considering the fact thatthe growth of gross domestic product, energy pro-duction and consumption are interrelated, growthof gross domestic product also demands increased

energy consumption. Consumption of liquid fuels inCroatia represents the main energy source in ourcountry. Considering Croatias geographic characte-ristics, as well as the economic importance of traf cand tourism for future development, it is estimatedthat the role of liquid fuels in energy consumption inCroatia will continue to be very important and thattheir share will not decrease signi cantly in the fo-llowing period until year 2020, and even until 2030. Itis expected that between 2020 and 2030 the share ofliquid fuels in the consumption structure will fall toa certain extent.

According to the bases for the elaboration ofCroatias Energy Sector Development Strategy, inthe basic scenario which includes a detailed anal-ysis of the nal energy consumption in industry, traf-c and general consumption, a rise in liquid fuelsconsumption is predicted in direct consumption atabout 2 % annually in the period until year 2030 andbased on that, fuel consumption as shown in Table 1and Figure 1 is predicted. Besides that, the estimatetook into consideration additional assumptions forestimate of consumption as well(economic growth,decrease of loss in oil processing, exchange of fuelsat re neries renovation, termination of operation offuel oil thermal power plants, provision of additio-nal oil quantities and derivatives for the needs of the

8/13/2019 Energy 0901

9/104


Tablica 1 Projekcija potronje tekuih goriva i potrebe za naftom [4]

Table 1 Projection of liquid fuels consumption and oil requirements [4]

Tablica 2 Bilanne rezerve i proizvodnja nafte i kondenzata u RH [4]Table 2 Oil and condensates balance reserves and production in Croatia [4]

mandatory and strategic oil reserves). Based onthese assumptions, long-term needs of domesticenergy markets for oil derivatives and crude oilare estimated.

i derivata za potrebe obveznih i stratekih zalihanafte). Na temelju ovih pretpostavki procijenjenesu dugorone potrebe domaih energetskih tri-ta za naftnim derivatima i sirovom naftom [5].

Godina /Year 2006. 2010. 2020.Stopa rasta potronje /

Consumption growth rate,%

2030.Stopa rasta potronje /

Consumption growth rate2020.2030.,

%Derivati /Derivatives106 t 4,8 5,2 5,8 1,3 6,5 1,2

Nafta /Oil106 t 5,0 5,4 6,2 1,6 6,9 1,1

Nafta iKondenzat /

Oil andcondensate

1990. 1995. 2000. 2001. 2002. 2003. 2004. 2005. 2006.

Rezerve /Reserves

103 m329 950 20 044 11 474 10 622 10 153 10 356 11 794 9 331 9 691

Proizvodnja /Production

103 t2 497 1 500 1 214 1 121 1 108 1 052 1 001 946 917

Slika 1 Projekcija potronje tekuih goriva i potrebe za naftomFigure 1 Projection of liquid fuels consumption and oil requirements

Proizvodnjom nafte i kondenzata na domaim ek-sploatacijskim poljima pokriva se oko 20 % doma-ih potreba za sirovom naftom. Kretanja preostalihbilannih rezervi nafte i kondenzata u Hrvatskoj urazdoblju od 1990. do 2006. godine prikazana su utablici 2 i slici 2, a proizvodnja na slici 3. One pred-stavljaju osnovu za procjenu budue proizvodnjenafte u RH. [3]

The production of oil and condensates on dome-stic exploitation elds covers about 20 % of dome-stic requirements for crude oil. Fluctuations of therest of the oil and condensates balance reserves inCroatia in the period from 1990 to 2006 are shownin Table 2 and Figure 2, and the production in Fi-gure 3. These represent the basis for the estimateof future oil production in Croatia.

8/13/2019 Energy 0901

10/104


Prilikom prorauna projekcija proizvodnje nafte ikondenzata za razdoblje do 2020. godine u obzir je uzeta budua proizvodnja nafte i kondenzata napostojeim domaim eksploatacijskim poljima.Nadalje je u obzir uzeta proizvodnja nafte prilikomuporabe metoda za poveanje iscrpka nafte(EORmetode) kao i proizvodnja nafte koja je ocijenjenakao mogua prilikom koritenja novih tehnika itehnologija. Procjena budue proizvodnje nafte uRH u razdoblju do 2020. godine prikazana je u ta-blici 3 i gra ki na slici 4.

Slika 2 Kretanje rezervi nafte u HrvatskojFigure 2 Oil reserves uctuation in Croatia

Slika 3 Proizvodnja nafte u HrvatskojFigure 3 Oil production in Croatia

When estimating the projections of oil and con-densates production for the period until 2020,future oil and condensates production on the exi-sting domestic exploitation elds has been takeninto consideration. Furthermore, oil productionwith the use of the Enhanced Oil Recovery Methodhas been taken into consideration, as well as oilproduction assessed as possible with using newtechniques and technologies. Estimate of futureoil production in Croatia in the period until 2020 isshown in Table 3, and graphically in Figure 4.

Godina /Year 2006. 2010. 2020. 2030.Nafta i kondenzat /Oil and condensate103 t 917 1 100 550 350

Tablica 3 Projekcija proizvodnje nafte u Hrvatskoj [4]Table 3 Projection of oil production in Croatia [4]

Slika 4 Projekcija proizvodnje nafte u HrvatskojFigure 4 Projection of oil production in Croatia

8/13/2019 Energy 0901

11/104


3 RAZLOZI ZA STRATEKEZALIHE NAFTE Na temelju iznesenih procjena, u razdoblju izme-u 2020. i 2030. godine udio domae proizvodnjeu podmirivanju energetskih potreba e i daljeopadati ime e rasti zavisnost gospodarstva Hr-vatske o uvoznoj nafti, koja e nakon 2020. godineiniti preko 90 % ukupnih potreba za naftom [3].Nakon 2020. godine osobito vano postaje uklju-ivanje energetske infrastrukture u infrastrukturuneposrednog i ireg okruenja, te diversi ciranjeopskrbe novim izvorima i osiguranje novih pravacauvoza. Glavni razlozi za stvaranje stratekih zalihanafte proizlaze iz temeljne potrebe osiguranja do-bave nafte u svim moguim okolnostima, odnosnoosiguranja opskrbe domaeg trita ak u sluajuprivremenog prekida stalne dobave nafte s meu-narodnih trita.

Razvijene zemlje uvoznice nafte ve nekoliko de-setljea nastoje opasnosti i potencijalne nestabil-nosti meunarodnog naftnog trita, kao i njihovodjelovanje na nacionalna energetska trita i su-stave, umanjiti stvaranjem stratekih zaliha nafte[6]. Strateke zalihe nafte organizirane su u oblikulogistikog i komercijalnog sustava za uskladite-nje odreenih koliina sirove nafte, koji je pod nad-zorom dravnih institucija ili tvrtki s javnim nad-zorom koje omoguuju skladitenje sirove nafte injezino putanje na trite u sluaju poremeaja[5]. Sustavom stratekih zaliha nafte se u sluaju

prekida ili smanjene opskrbe domaeg naftnogtrita, omoguuje dobava dodatnih koliina nafteza osiguravanje normalne opskrbe tijekom trajanja trinog poremeaja, odnosno poremeajauvoza nafte redovitim sredstvima i mehanizmima[7]. Dosadanje iskustvo pokazalo je kako zemljeuvoznice nafte, koje imaju strateke zalihe nafte,zajedno s obveznim zalihama naftnih derivata,imaju visok stupanj sigurnosti opskrbe naftom i to je znaajna komponenta energetske, gospodarskei ukupne nacionalne sigurnosti [8].

4 PROCJENA UGROENOSTIHRVATSKOG GOSPODARSTVAU POGLEDU MOGUIH PREKI-DA DOBAVE NAFTEHrvatska samo djelomino podmiruje svoje po-trebe za energentima proizvodnjom nafte i pri-rodnog plina, dok vei dio uvozi. Vlastita opskr-bljenost ukupnom primarnom energijom je 1988.godine iznosila 65 %, 2000. godine 50 %, a 2005.godine oko 45 %. Prema predvianjima, prateidosadanji trend smanjenja, 2030. godine vlasti-ta opskrbljenost ukupnom primarnom energijome iznositi svega 21 % do 23 %. S obzirom na na-

3 REASONS FOR STRATEGICOIL RESERVESBased on the presented estimates, in the periodbetween 2020 and 2030, the share of domesticproduction in the settlement of energy require-ments will continue to fall and, because of that,the dependence of Croatias economy on impor-ted oil will grow and constitute over 90 % of totaloil requirements after year 2020. After 2020, whatbecomes especially important is the inclusion ofthe energy infrastructure into the infrastructureof the direct and wider environment and the di-versi cation of the supply with new sources andprovision of new import routes. The main reasonsfor creating strategic reserves arise from the ba-sic need of insurance of oil supply in all possiblecircumstances, that is, insurance of supply for thedomestic market, even in the case of temporarydisruption of continuous oil supply from interna-tional markets.

For several decades now, developed oil impor-ting countries have been trying to ameliorate thedangers and potential instabilities of the interna-tional oil market, as well as their impact on na-tional energy markets and systems, by creatingstrategic oil reserves. Strategic oil reserves areorganized in the form of a logistic and commercialsystem for storage of certain quantities of crudeoil and the release thereof onto the market in caseof disruption. In case of disruption or decreasedsupply of the domestic oil market, the system ofstrategic oil reserves enables the supply of additi-onal oil quantities for insurance of normal supplyfor the duration of market disruption, that is, forthe duration of the disruption of oil import by re-gular means and mechanisms. The experience sofar has shown that oil importing countries, whichhave strategic oil reserves, along with mandatoryoil derivatives reserves, also have a high level of oilsupply security and that is an important elementof the energetic, economic and overall nationalsecurity.

4 ESTIMATE OF THE ENDAN-GERMENT OF CROATIA INVIEW OF POSSIBLE OIL SUP-PLY DISRUPTIONSCroatia settles its requirements for energy sour-ces only partially by oil and natural gas productionwhile it imports the larger part thereof. Own su-pply of overall primary energy amounted to 65 %in 1988, 50 % in 2000, and about 45 % in 2005.According to the estimates, and following the for-mer decrease trend, in 2030 own supply of overallprimary energy will amount to only 21 % to 23 %.

8/13/2019 Energy 0901

12/104


vedena predvianja, vidljivo je da e Hrvatskasve vie ovisiti o uvozu energenata, prvenstvenonafte. Nakon 2015. godine, proizvodnja nafte eznaajnije padati, a uvoz intenzivno rasti. Iz svevee uvozne zavisnosti proizlazi i porast osjet-ljivosti energetskog sektora i time cjelokupnoggospodarstva RH o zbivanjima i moguim pore-

meajima na meunarodnim tritima energije.Izloenost gospodarstva Hrvatske oscilacijamameunarodnih energetskih trita nakon 2015.godine raste, kad se ocjenjuje da e uvoz nafteprijei 85 % potreba, te posebno nakon 2020. go-dine, kad e uvoz nafte premaivati 90 % doma-ih potreba, te se ocjenjuje da raste i ugroenostgospodarstva u pogledu moguih prekida doba-ve nafte [3].

Za funkcioniranje pouzdanog i odrivog energet-skog sektora, potrebno je osigurati strateke za-lihe nafte i u skladu s time ugovoriti nove koliineza dobavu prema postojeim planovima razvojatransportnog sustava i potronje, kako bi se upostojeim trinim i meunarodnim geopoli-tikim prilikama osiguralo maksimalno mogueunaprjeenje energetske sigurnosti Hrvatske.Cilj je osigurati organizacijske pretpostavke, pla-nove i mjere za razvitak stratekih zaliha nafte,pri emu su tri glavne funkcije stratekih zaliha.Sigurnosna, u smislu poveanja sigurnosti op-skrbe naftom i podizanja energetske sigurnosti,gospodarska, budui da strateke zalihe stabi-lizirajue djeluju na gospodarstvo i njegov polo-aj u okruenju, te geopolitika, zbog stvaranjakonkurentskih prednosti gospodarstva Hrvatskeu odnosu na svoje neposredno okruenje.

5 ZAKLJUAKU smislu osiguravanja opskrbe naftom u Hr-vatskoj je potrebno osposobljavanje energet-skog sustava, prvenstveno Hrvatske agencije zaupravljanje zalihama naftnih derivata(HANDA) za pripremu, organizaciju i uspostavu sustava zastrateke zalihe nafte, te osposobljavanje doma-

ih kompanija INA, JANAF, i drugih za stvaranjeinfrastrukturnih pretpostavki formiranja strate-kih zaliha nafte. Nadalje je potrebna prilagodbaorganizacijskog i nancijskog sustava stratekihzaliha u skladu sa zakonskim i drugim propisi-ma.

Prosudba potrebnih skladinih kapaciteta izvre-na je prema projekciji kretanja budue potronjenafte u Hrvatskoj, a uzimajui u obzir minimalnopotrebne skladine kapacitete kao poetak ra-zvitka stratekih zaliha do razine od 90-dnevneprocijenjene godinje potronje nafte. Kako bise omoguio razvoj stratekih zaliha nafte po-trebno je osigurati dodatne skladine kapacite-

Considering the above predictions, it is obvious thatCroatia will increasingly depend on the import ofenergy sources, oil primarily. After year 2015, oilproduction will fall more signi cantly, and importwill grow intensively. The increasingly extensivedependence on import also gives rise to an incre-ased sensitivity of the energy sector and therefore

of the entire economy of Croatia to the events andpossible disruptions on international energy mar-kets. Croatias exposedness to the oscillations ofinternational energy markets after year 2015 rises,when it is estimated that oil import will exceed 85 %of requirements, and especially after 2020, when oilimport will exceed 90 % of domestic requirements.Endangerment of the economy in view of possibleoil supply disruptions is also estimated as growing.

The functioning of a reliable and sustainable energysector requires the insurance of strategic oil reser-ves and, in accordance with that, the contractingof new supply quantities according to the existingplans of development of the transport system andconsumption, so as to enable the maximum possi-ble improvement of Croatias energy supply securityin the existing market and international geopoliticalcircumstances. The objective is to provide organiza-tional assumptions, plans and measures for the de-velopment of strategic oil reserves, whereat thereare three main functions of strategic reserves. Thesecurity function, in the sense of increased secu-rity of oil supply and improving the level of energysecurity; the economic function, because strategicreserves have a stabilizing effect on the economyand its position in the environment; and the geopo-litical function, because of creation of competitiveadvantages of Croatias economy in relation to itsdirect environment.

5 CONCLUSIONFor the purpose of insuring oil supply in Croatia, it isnecessary to capacitate the energy system, prima-rily the Croatian Agency for Oil Derivatives ReservesManagement(HANDA) for the preparation, organi-

zation and establishment of a system for strategicoil reserves, and to capacitate domestic companiesINA, JANAF, and other for the establishment of in-frastructural assumptions for the formation of stra-tegic oil reserves. Furthermore, an adjustment ofthe organizational and nancial strategic reservessystem in accordance with legal and other regulati-ons is also necessary.

The estimate of necessary storage capacities hasbeen performed according to the projection of fu-ture oil consumption uctuation in Croatia, andthat by taking into consideration the minimumnecessary storage capacities as the beginning ofthe development of strategic reserves up to the

8/13/2019 Energy 0901

13/104


te. Ukupne potrebe za skladinim kapacitetimaprocjenjuju se na 1,4 milijuna tona u 2012. go-dini te oko 1,55 milijuna tona 2020. godine, toodgovara ukupno potrebnim skladinim kapaci-tetima oko 1 640 000 m3 2012. godine, odnosno1 820 000 m3 2020. godine.

Takoer je potrebna izgradnja skladinih kapaci-teta za osiguranje 90-dnevnih potreba Hrvatskedo 2012. godine, to uz postojee skladine ka-pacitete od 960 000 m3 ili oko 820 000 tona, nala-e izgradnju kapaciteta za novih 600 000 tona ili700 000 m3 do 2012. godine, te razvoj dodatnihskladinih kapaciteta i izgradnju novih skladitaod daljnjih 150 000 tona ili oko 180 000 m3nakon2012. do 2020. godine.

Osnivanje znaajnijih kapaciteta za strateke za-lihe nafte ili za meunarodnu ponudu skladinihkapaciteta zahtijevala bi obilnije dimenzioniranje

skladita i skladinih kapaciteta.

level of 90-day estimated annual oil consumption.In order to enable the development of strategic oilreserves, it is necessary to insure additional stora-ge capacities. Total requirements for storage ca-pacities are estimated at 1,4 million tons in 2012,and about 1,55 million tons in 2020, which suitsthe totally necessary storage capacities of about

1 640 000 m3

in 2012, that is, 1 820 000 m3

in 2020.The construction of storage capacities for the insu-rance of 90-day Croatias requirements up to 2010 isalso necessary, and this, along with the existing sto-rage capacities of 960 000 m3 or about 820 000 tons,requires the construction of capacities for another600 000 tons or 700 000 m3 until 2012, and the de-velopment of additional storage capacities and con-struction of new warehouses of another 150 000 tonsor about 180 000 m3 after year 2012 and up to 2020.

Creation of signi cant capacities for strategic oil re-

serves or for the international offer of storage capaci-ties would require a more extensive dimensioning ofthe warehouse and storage capacities.

LITERATURA / REFERENCESADAMS, N., Terrorism & Oi,. PennWell, Tulsa, 2002[1]DEKANI, I.; KOLUNDI, S.; KARASALIHOVI, D., Stoljee nafte: Veza izmeu nafte, novca i moi koja[2] je promijenila svijet,. Drugo izmijenjeno i dopunjeno izdanje. Naklada Zadro, Zagreb, 2004.Republika Hrvatska, Ministarstvo gospodarstva, rada i poduzetnitva, Energija u Hrvatskoj, Godinji en-[3]ergetski pregled 2006., Zagreb, 2007.Ministry of Economy, Labor and Entrepreneurship, Prilagodba i nadogradnja Strategije energetskog raz-[4]

vitka Republike Hrvatske, Nacrt Zelene knjige, Zagreb,(2008-07-17)Energy Information Administration, Of cial Energy Statistics from the U.S. Government;[5] http://www.eia.doe.gov / (2008-09-21)BP Statistical Review of World Energy 2008,[6] http://www.bp.com (2008-10-12)A European Strategy for Sustainable, Competitive and Secure Energy, COM[7] (2006), http://ec.europa.eu/energy/green-paper-energy/index_en.htm (2008-04-28)The National Security Strategy of the United States of America, The White House, Washington, March,[8]2006 http://whitehouse.gov. (2006-03-20)

Authors Adresses:

Assistant Prof.Daria Karasalihovi Sedlar, [email protected] Dekani, [email protected] Hrnevi, [email protected] of ZagrebFaculty of Mining, Geology and PetroleumEngineeringPierottijeva 6, 10000 ZagrebCroatia

Manuscript received on:2009-01-22

Accepted:2009-02-05

Adrese autora:

Doc. dr. sc.Daria Karasalihovi [email protected]

Prof. dr. sc.Igor [email protected]

Dr. sc.Lidia Hrnevi [email protected] u Zagrebu

Rudarsko-geoloko-naftni fakultetPierottijeva 610000 Zagreb

Hrvatska

Urednitvo primilo rukopis:2009-01-22

Prihvaeno:2009-02-05

8/13/2019 Energy 0901

14/104

8/13/2019 Energy 0901

15/104

8/13/2019 Energy 0901

16/104

Grubii, N., Dugoroni izgledi cijena nafte i plina, Energija, god. 58(2009 ), br. 1., str. 14-25Grubii, N., Long-Term Prospect of Oil and Gas Prices , Energija, vol. 58(2009 ), No. 1, pp. 14-25 16

1 UVOD

Velike oscilacije cijena nafte na svjetskom tritu,relativno bre i znaajnije od poetka sedamde-setih godina, kao bogom su dane za izradu ra-zliitih scenarija buduih zbivanja i cijena nafte iplina na svjetskom tritu.

Autori scenarija, uglavnom ameriki, gotovo senatjeu u pogaanju i grijeenju oko oekiva-nih kretanja cijena nafte(slika 1 ). To stoga jer je atraktivno(stvar prestia), ali i nemogue po-goditi kretanje cijena nafte(zbog neoekivanihfaktora utjecaja i problem njihove kvanti kacije),tako da im je bila osigurana dugotrajna i zabavnaigra. Razlog tome je to se ne zarauje samo naproizvodnji nafte, ve i na njenoj cijeni. Tonije,na promjeni te cijene. A zarade na promjeni cijene su velike, koji puta vee od zarade na samojproizvodnji nafte.

1 INTRODUCTION

Signi cant oscillations of prices on the world mar-ket, which are relatively quicker and more signi cantthan they were at the beginning of the seventies, areas if god-given for the elaboration of different sce-narios of future events and oil and gas prices on theworld market.Authors of scenarios, mostly Americans, are almostcompeting in guessing and mistaking the expectedprices uctuations(Figure 1). That is because it isattractive (a matter of prestige) but also impossi-ble to guess the oil prices uctuations(because ofunexpected impact factors and the problem of theirquanti cation), so that they will surely be enjoying alasting and fun game. The reason for that is the factthat oil production is not the only source of pro t,but its price as well. More precisely, the change ofthat price. And pro ts from price changes are gre-at, sometimes even greater than the pro ts from oilproduction itself.

Slika 1 Kretanje cijene nafte Brent [2]Figure 1 Oil prices uctuations Brent [2]

Nakon puno godina igranja, promatrai su,izgleda, postali svjesni nemogunosti toneprocjene zbivanja na svjetskom tritu naf-te. Jedan od direktora Agencije za energetikuOECD-a(Georg Lamsden) na pitanje o oeki-vanoj cijeni barela nafte, sad ve davne 1991.godine odgovorio je, kako se toan odgovormoe dobiti samo u raju za budale. Osobnobih otiao tako daleko i oprezno se suglasio snajmudrijim strunjacima koji predviaju dae se cijene nafte kretati izmeu 20 USD/bbl i 150 USD/bbl.

Unato oprenim miljenjima o procjenjivanjukretanja cijena nafte, znanstveno je mogue

After years of playing the game, the spectatorshave apparently become aware of the impossibilityto estimate accurately the events on the world oilmarket. When asked about the expected price ofthe oil barrel, one of the directors of the Internati-onal Energy Agency of the OECD(Georg Lamsden),as early as in 1991, replied that the exact answercan only be gained in fools paradise. I would perso-nally go that far and carefully agree with the wisestexperts who predict that oil prices will uctuatebetween 20 USD/bbl and 150 USD/bbl.

In spite of contradictory opinions on the estimationsof oil prices uctuations, it is scienti cally possible

8/13/2019 Energy 0901

17/104

Grubii, N., Dugoroni izgledi cijena nafte i plina, Energija, god. 58(2009 ), br. 1., str. 14-25Grubii, N., Long-Term Prospect of Oil and Gas Prices , Energija, vol. 58(2009 ), No. 1, pp. 14-2517

odrediti granice, unutar kojih se, uz odreenuvjerojatnost, moe oekivati njeno kretanje. Dabi uz visoku vjerojatnost te granice bile to bo-lje pogoene(to preciznija procjena), nuno jeidenti cirati i kvanti cirati faktore koji determi-niraju kretanja cijena nafte, te ekonometrijskimmodelima izvriti procjene.

2 GRANICE RASPONA CI-JENE

Minimalna cijena, odreena je uvijek(za oskud-ne resurse) maksimalnim(graninim) trokovi-ma proizvodnje, uveanim za pro t. Isti zakonvrijedi i za donju granicu cijene nafte. Tu granicue uvijek odreivati trokovi proizvodnje posljed-nje potrebne, dakle najskuplje, jedinice proizve-dene nafte.

Za razliku od minimalne cijene, koja je odre-ena trokovima proizvodnje nafte, maksimal-na cijena je odreena platenom spremnou(sposobnou) potroaa naftnih derivata, kojase obino iskazuje kroz elastinost tranje de-rivata nafte.

Cijene e se uvijek kretati unutar tih dviju grani-ca. Problem je jedino u tome to su maksimalnitrokovi proizvodnje nafte uvijek puno nii odplatene spremnosti potroaa. Upravo zbogveliine te razlike, prisutne su i velike oscilacijecijena. Ta injenica pospjeuje trgovinu s cijena-ma (ugovorima).

U uvjetima krize dolazi do kontrakcije potro-nje, smanjuje se potranja, pa se i graninaproizvodnja trokovno pomie nanie. S njome,nanie se pomie i minimalna cijena. U uvjeti-ma gospodarske ekspanzije, razliitim nan-cijskim instrumentima poveava se platenaspremnost potroaa, jaa trgovina ugovorima,a s time ekspandira i maksimalna cijena nafte.Dakle, dok je minimalna cijena nafte odreenarealnim faktorom, trokom, maksimalna cijena

nafte odreena je trinim, pekulativnim para-metrima.

Na slici 1 se vidi da su uspostavljene graniceuktuacije cijene nafte izmeu 30 USD/bbl i150 USD/bbl. U regularnim uvjetima cijenanafte e uktuirati u tom rasponu. Izvanredneokolnosti u uvjetima krize ili prosperiteta moguodrediti i iri okvir uktuacije.

3 FAKTORI DETERMINACIJE

Pri sagledavanju budueg kretanja cijena naf-te (i plina) na svjetskom tritu nuno je luiti

to determine the boundaries within which, with acertain probability, their uctuation can be expected.In order to guess as closely as possible those boun-daries with a high level of probability(the most deta-iled estimate possible), it is necessary to identify andquantify the factors which determine the oil pricesuctuations, and to undertake estimations by virtue

of econometric models.

2 BOUNDARIES OF PRICERANGES

Minimum price is always determined(for scarce re-sources ) by maximum(cut-off) production costs in-creased by pro t. The same rules apply to the loweroil price boundary. That boundary will always be de-termined by production costs of the last required, thatis, of the most expensive unit of the produced oil.

Unlike the minimum price which is determined by oilproduction costs, the maximum price is determinedby the paying capacity of the consumers of oil deriva-tives, and this capacity is usually shown through theelasticity of demand for oil derivatives.

The prices will always uctuate between those twoboundaries. The only problem is that maximum oilproduction costs are always signi cantly lower thanthe consumers paying capacity. Exactly due to theextent of that difference, great price oscillations arealso present. That fact enhances the price(contract) trade.

In the circumstances of crisis, there occurs a con-traction of consumption, demand decreases, and so,in view of costs, the cut-off production also movesdownward. And with the cut-off production, the mi-nimum price moves downward as well. In the cir-cumstances of economic expansion, various nanci-al instruments are used to increase the consumerspaying capacity, strengthen the contract trade, andconcurrently expand the maximum oil price as well.Therefore, while the minimum price of oil is determi-ned by the real factor- the cost, the maximum price

of oil is determined by the market - the speculativeparameters.

Figure 1 shows that oil price uctuation bounda-ries have been set up between 30 USD/bbl and150 USD/bbl. In regular conditions, the price of oilwill uctuate within that range. Extraordinary con-ditions in the circumstances of a crisis or prosperitymay determine a wider uctuation range.

3 DETERMINATION FACTORS

When contemplating the future oil(and gas) priceuctuation on the world market, it is necessary to

8/13/2019 Energy 0901

18/104


kratkorone poremeaje od dugoronih faktoradeterminacije kretanja na svjetskom tritu naf-te (i plina) (slika 2 ).

Kratkorone poremeaje ine razni oblici pri-rodnog ili drutvenom podrijetla, lokalnog ka-raktera, bez mogunosti znaajnijeg utjecaja

na globalna zbivanja, na svjetskom tritu nafte(i plina). Premda kratkorono mogu dovesti domanjih ili veih poremeaja na svjetskom tritunafte(i plina), ti faktori nisu od veeg znaenja prisagledavanju dugoronih kretanja cijena nafte(iplina).

Dugoroni, tj. faktori determinacije kretanja nasvjetskom tritu su od presudne vanosti zakretanja cijena nafte i plina.

Zapadnim ekonomijama, posebno privredi SAD,imanentni su izraeni ciklusi u razvoju. Ameri-

ki ekonomisti su, uglavnom prestrukturiranjemprivrede, uspijevali prilino dobro rjeavati pro-bleme recesije, u prolom stoljeu.

Kao i vie puta prije toga, tijekom 1990. godine,ameriki ekonomisti su ustanovili prve znakovenadolazee recesije. Dolo je do pada privredneaktivnosti, rasta nezaposlenosti i in acije. To jebio dovoljan znak State Departmentu da se morapozabaviti s vrlo ozbiljnim problemom. Kako jetijekom 80-tih godina ve izmijenjena gotovocjelokupna privredna struktura zemlje, to je tamogunost u svrhu oivljavanja privrede, ovaj

puta iskljuena. Vrlo prikladno, meutim, moglo je posluiti iznalaenje trita koje e apsorbirativelike koliine industrijskih proizvoda. I krenulo je s tzv. globalizacijom. Mobilnost proizvodnihfaktora pogodovala je njihovu seljenju na jeftinijapodruja, ponajvie u Kinu, Indiju i istonu Eu-ropu.

Ako se uz to ostvari jo i jeftina energija, onda jeuspjeh siguran. Smanjenjem trokova proizvod-nje pridonosi se eliminaciji razornog djelovanja(trokovne) in acije po razvijene zapadne ekono-mije. Tako je i bilo. Stvorena su golema nova po-troaka podruja, i kapitalizmu je bilo zagaran-tirano preivljavanje iduih 1 do 2 krizna ciklusa(8 do16 godina).

Novi krizni ciklus, uslijedio je 2000. do 2003. go-dine. Rije je o tzv. dot-com krizi, i relativno jelako svladana. Novi ciklus gospodarskog rastavrlo brzo je dosegao prethodne vrhunce. Finan-cijska aktivnost razvila se do nesluenih razmje-ra. Obilje raspoloiva novca pogodovalo je rastupotranje, irenju nancijske industrije, ali i za-postavljanju realnog sektora gospodarstva. Bila je to klica nove krize.

excrete short-term disturbances from long-termuctuation determination factors on the world oil

(and gas) market(Figure 2).

Short-term disturbances include various forms ofnatural or social origin and local character, wit-hout the possibility of signi cant impact on global

events on the world oil(and gas) market. Althoughin the short-term they may lead to minor or grea-ter disturbances on the world oil(and gas) market,those factors are not of greater signi cance whencontemplating long-term oil(and gas) prices uc-tuations.

Long-term factors, that is, determination factors ofworld market uctuations, are of key importancefor uctuations of oil and gas.

Pronounced development cycles are immanent towestern economies, especially to the economy of

the USA. In the past century, mostly by re-structu-ring the economy, the American economists havebeen quite successful in solving the recession pro-blems.

Just as many times before, during 1990, Americaneconomists established the rst signs of the upco-ming recession. There occurred a fall in the econo-mic activity, growth in unemployment and in ation.That was a sign indicative enough for the State De-partment to realize that they have to deal with a veryserious problem. As almost the entire economicstructure of the country had been modi ed during

the 80s, that possibility for the purpose of revival ofeconomy is excluded this time. However, nding amarket which would absorb great amounts of in-dustrial products could have been very expedient.And the so-called globalization was launched. Themobility of production factors favoured their movingto cheaper regions, mostly to China, India and Ea-stern Europe.

If cheap energy is also realized along with that, thensuccess is ensured. The reduction of production co-sts contributes to the elimination of the destructiveeffect of the(cost ) in ation on the western econo-mies. And that is what happened. Enormous newconsumer areas were created and capitalism wasguaranteed to survive the next 1 to 2 crisis cycles(8 to 16 years).

The new crisis cycle ensued in 2000 to 2003. Thematter at hand is the so-called dot-com crisis andit was overcome relatively easily. The new cycle ofeconomic growth reached the peaks of the previousperiod very quickly. Financial activity developed tounexpected proportions. An abundance of availablemoney favoured the growth of demand, expansionof the nancial industry but also the neglecting ofthe real economy sector. That was the seed of thenew crisis.

8/13/2019 Energy 0901

19/104


A onda je uslijedila aktualna kriza. Greka u -nancijskoj sferi(zbog kolapsa hipotekarnog tri-ta u SAD-u) dovela je do otkrivanja svih sustav-nih slabosti. Bez kvalitativno novih proizvoda, re-alni sektor ostajao je bez jednog po jednog dijelapotranje, pa je i sam zavrio u krizi [1].

Gotovo nulte kamate na kratkorone pozajmicenovca amerikoj dravi ukazuju na prestanakmeusobnog nanciranja banaka, odnosno gos-

podarstva od strane banaka. Tek kad pone ra-sti potranja za novcem, doi e i do oivljavanjagospodarske aktivnosti u SAD-u, a prva indikaci- ja e biti porast kratkoronih kamatnih stopa.

And then the present crisis ensued. A mistake inthe nancial sphere(because of the collapse of themortgage market in the USA) brought about theuncovering of all system weaknesses. Without qu-alitatively new products, one by one, the real sectorremained without parts of the demand and endedup in crisis itself [1].

Almost zero interest on short-term money loans in-dicated to USA that the inter- nancing of the banks,

that is, the nancing of the economy by the bankscame to a stop. A revival of the economic activity inthe USA will not happen before the demand for mo-ney starts to increase, and the rst indication of thiswill be the growth of short-term interest rates.

Slika 2 Kretanje vrijednosti S&P 500 indeksa [2], [3]

Figure 2 S&P 500 index value uctuation [2], [3]

Slika 3 Kretanje kamatne stope na 3-mjesene trezorske zapise u SAD [2]Figure 3 Fluctuations of interest rates on 3-month treasury securities in USA [2]

8/13/2019 Energy 0901

20/104


Jedan od najznaajnijih faktora determinacije jeUSD(ameriki dolar) obraunska i valuta plaa-nja u svjetskoj trgovini naftom. Iz ove konstatacije,uoljiva je dihotomija dolara, i to, kao nacionalnevalute SAD-a i kao obraunske i valute plaanja usvjetskoj trgovini naftom.

Dakle, politikom teaja, SAD preko dolara izravnomogu i utjeu na cijenu nafte.

One of the most important determination fac-tors is the USD(American dollar) accounting andpayment currency in world oil trade. This fact alsoreveals the dichotomy of the dollar, and that bothas the USA national currency, and as the accoun-ting and payment currency in world oil trade.

Therefore, by virtue of the currency politics, theUSA can and do directly in uence the price of oil.

Slika 4 FOREX paritet USD/EUR [2]Figure 4 FOREX USD/EUR parity [2]

Primjerice, sredinom prole godine cijena ame-rikog dolara je pala ispod 0,7 EUR. Na taj na-in je realna vrijednost nafte bila znaajno niaod njene nominalne vrijednosti(u to doba iznad100 USD/bbl).

Pored svjesne politike vlade SAD-a u ostvarivanjusvojih interesa politikom teaja dolara, na vrijed-nost dolara, pa dakle i na cijenu nafte, izravnoutjeu i privredne i budetske prilike SAD-a.

Zbog uestalog ponavljanja, kao faktor determi-nacije, moe se promatrati i nedisciplina lanica

OPEC-a u pridravanju dogovorenih proizvodnihkvota. Upravo to je bio osnovni uzrok uestalognaruavanja odnosa ponude i potranje nafte sizravnim reperkusijama na ravnotenu cijenunafte na svjetskom tritu.

Rast cijena nafte jo tamo, od poetkom 70-tihgodina, donio je veliki kapital zemljama izvozni-cama nafte, ali je doveo i do sve vee supstitucijenafte(u potronji) gdje je to bilo mogue(svugdjeosim u transportu), pa i do intenziviranja procesarazvoja energetski racionalnijih tehnologija.

Istodobno, rast cijena nafte, omoguio je racio-nalnu proizvodnju nafte i onim zemljama, izvan

For example, in the middle of last year, the price ofthe American dollar fell bellow 0,7 EUR. Thus thereal oil value was signi cantly lower than its nomi-nal value(higher than 100 USD/bbl at that time).

The value of the dollar, and therefore the price ofoil as well, is not only in uenced by the purposefulpolitics of the US Government in attainment of theirinterests by virtue of the dollar currency politics, butthese are also directly in uenced by economic andbudgetary circumstances in the USA.

Because of the frequency of repetition, the lack of

discipline of the OPEC member states in complyingwith the agreed production quotas can also be vi-ewed as a determination factor. This was the veryreason of frequent disturbances of the oil offer anddemand ratio, with direct repercussions on the ba-lanced oil price on the world market.

Back in the beginning of the 70s, the growth of oilprices brought great capital to the oil exportingstates, but it also brought about increasing sub-stitution of oil(in consumption) wherever possible(everywhere except in transport), and even intensi-ed the development process of energetically morerational technologies.

8/13/2019 Energy 0901

21/104


OPEC-a, gdje se to do tada nije isplatilo, zbogvisokih trokova eksploatacije.

Osnovni ekonomski interes SAD-a je jaka i sve jaa privreda zemlje, s ulogom nosioca svjetskogprivrednog razvoja. Za to je nuna stabilnost uvje-ta privreivanja, prije svega kroz stabilnu cijenu

energije, koju je mogue ostvariti kroz stabilneodnose ponude i potranje na svjetskom trituenergenata.

Tom interesu sueljen je interes dijela zemaljaizvoznica nafte. Privredno nerazvijene zemlje, ilimanje razvijene zemlje, teile su za samostalnimraspolaganjem nad vlastitim izvorima mineral-nih sirovina i pro tima od njihove eksploatacije,prije svega od nafte.

Na kraju, svemu tome treba suprotstaviti inte-rese sudionika nancijskih trita. Obino se u

predkriznim vremenima pojaava trgovina ugo-vorima radi kompenzacije gubitaka iz realnogsektora. Uz hranu, najprikladnija za to je nafta,zbog relativno niske cjenovne elastinosti po-tronje. Kad kompenzacija ne uspije, ulazi seu krizu. Paralelno s time kontrahira trgovinaugovorima i cijena nafte svodi se na minimalnu,trokovno de niranu.

4 PREDVIDIVI FAKTORI DE-TERMINACIJE ZA BUDUE

RAZDOBLJEZa razliku od ranijih kriza svijet je u 2009. godinuuao u pratnji dvaju ekonomskih problema, sma-njene privredne aktivnosti(recesije) i smanjenjacijena. Kao posljedica tih dvaju faktora javlja sepad zaposlenosti, a sve ozbiljnija postaje i pri- jetnja de acije. Za razliku od prethodnih kriznihsituacija, s in acijom, za ovaj sluaj ne postojeisprobani recepti ozdravljenja gospodarstva.

Do sada su ve aktivirane gotovo sve kratkoro-ne mjere (smanjenje kamatnih stopa, emisijenovca, dravni otkup dugova, dravna nancijskapomo bankama i poduzeima) tek s manjimuspjehom na ublaavanju posljedica gospodar-ske kontrakcije.

U takvim okolnostima izvjesno je daljnje kontra-hiranje gospodarske aktivnosti, pa i potranje zanaftom.

Uz nepromijenjene uvjete gospodarsko oivlja-vanje mogue je oekivati u iduih 3 do 5 godina,kao posljedicu rasta potranje za trajnijim ro-bama koje e u meuvremenu biti zamijenjenenovima, zbog dotrajalosti.

At the same time, the growth of oil prices enabledmore rational oil production in those countries aswell, outside of OPEC, where it was formerly unpro-table due to high exploitation costs.

USAs basic interest is a strong, and increasinglystronger, national economy, with the role of the

carrier of the world economic development. Thatrequires stable economic conditions, primarily thro-ugh stable energy prices which can be achieved bystable offer and demand ratios on the world energysources market.

The said interest is confronted by the interest of apart of the oil exporting states. Economically unde-veloped countries or less developed countries stri-ved for an independent disposal of own mineral rawmaterial sources and pro ts from their exploitation,primarily from oil.

Finally, all of this should be confronted by the inte-rests of the participants of the nancial markets. Inthe pre-crisis periods, the contract trade usually in-tensi es for the purpose of compensation of lossesfrom the real sector. Besides food, oil is the mostsuitable instrument for that purpose because of itslow consumption price elasticity. When the com-pensation is unsuccessful, a crisis emerges. Simul-taneously, contract trade contracts, and the price ofoil drops to the minimum, cost-de ned, price.

4 PREDICTABLE DETERMINA-TION FACTORS FOR THE FU-TURE PERIOD

Unlike the former crises, the world entered 2009accompanied by two economic problems - reducedeconomic activity(recession) and reduced prices.The consequence of those two factors is a fall inemployment, and the threat of de ation is also be-coming more serious. Unlike the former crisis situ-ations, with in ation, there are no tested recipes forthis case for the recovery of economy.

So far, almost all short-term measures(reductionof interest rates, money emission, state redemptionof debt, state nancial aid to banks and companies) have been activated with only slight success in theamelioration of the consequences of the economiccontraction.

In such circumstances, further contraction of eco-nomic activity, as well as of oil demand, is certain.

If the conditions do not change, economic revivalcan be expected in the next 3 to 5 years as a con-sequence of growth of demand for more durablegoods which will be replaced by new ones in themeantime, due to their state of dilapidation.

8/13/2019 Energy 0901

22/104

8/13/2019 Energy 0901

23/104


Nakon dosezanja dna krize, i zapoinjanja gospo-darskog oporavka, uslijedit e i oporavak cijenenafte. Na krai rok cijena nafte bi mogla porastido razine oko 50 USD/bbl, odnosno srednjoronodo 70 USD/bbl, otprilike.

Izlaskom iz krize nastupit e ponovno oivljavanjetrgovanja cijenama i daljnjeg rasta cijene nafte svedo prethodnih vrhunaca.

Sukladno ciklinosti razvoja amerikog gospodar-stva vrhunac gospodarskog prosperiteta moe seoekivati oko 2017. godine.

5 ZAKLJUAKCijena nafte bila je i ostat e vjerni pratilac zbiva-nja u svjetskom gospodarstvu. tovie, kao jedanod najboljih indikatora zdravlja svjetske ekonomi- je, napose amerike kao vodee i po veliini i porazvijenosti.

U kraem dolazeem razdoblju cijena nafte eoscilirati izmeu 25 USD/bbl i 70 USD/bbl, u ra-stuem trendu. Dugorono, cijena nafte e bitiusmjerena prema 150 USD/bbl.

Moe se oekivati da e ponuda nafte na svjetskomtritu do 2020. godine moi zadovoljiti potranju.Zalihe i iscrpljivanje pliih i jeftinijih izvora nafte,oekuje se, jo uvijek nee znaajnije utjecati narazinu postojeih marginalnih trokova proizvod-nje. Stoga se ne oekuje niti rast minimalne razinecijena nafte do 2020. godine.

Ocjene kretanja cijena prirodnog plina su ostaleu sjeni ocjena kretanja cijena nafte, upravo zbog

Slika 6 Tehnika analiza Kretanje cijene nafte Brent [2]

Figure 6 Oil Price Fluctuation technical analysis Brent [2]

After the bottom of the crisis has been reachedand the economic recovery has started, the reco-very of oil prices will ensue. In the short-term, oilprices might grow up to the level of 50 USD/bbl,that is, to approximately 50 USD/bbl in the middleterm.

After the crisis ends, a revival of prices trade andfurther oil price growth will ensue again all up tothe former levels.

Following the cyclicality of the development of theAmerican economy, a peak of the economic pros-perity can be expected around 2017.

5 CONCLUSIONThe price of oil has always been, and will remain,a loyal companion of the events in the world eco-nomy. Moreover, it will remain one of the best indi-cators of the soundness of world economy, espe-cially American as it is the leading economy bothaccording to size, and to the level of development.In the shorter upcoming period, price of oil will os-cillate between 25 USD/bbl and 70 USD/bbl withan upward trend. In the long-term, the price of oilwill move towards 150 USD/bbl.

Oil offer on the world market until 2020 can beexpected to successfully meet the demand. Reser-ves and exploitation of more shallow and cheaperoil sources are not expected to impact signi cantlythe level of existing marginal production costs yet.Therefore, growth of the minimum oil price levelsis not expected either until 2020.

8/13/2019 Energy 0901

24/104


toga, jer su cijene prirodnog plina pri meunarod-noj trgovini i razmjeni izravno zavisne o cijenamanafte (derivata nafte). Tonije, o cijeni niskosum-pornog loivog ulja, kao derivatu nafte.Cijene energenata, openito, nuno moraju biti umeusobnoj korelaciji, kako bi se mjerama eko-nomske politike, upravo preko tih cijena, usmjera-

vala potronja pojedinih energenata, ovisno o ci-ljevima dane ekonomske politike. Takve promjenemogu izazvati samo glavni svjetski potroai i/iliglavni svjetski proizvoai energenata.

Moe se oekivati blago jaanje cijena prirodnogplina prema cijenama nafte, zbog djelovanja nizafaktora na rast potranje za prirodnim plinom,iduih godina. Uz ve izgraenu transportnu infra-strukturu (plinovode), brojnost potroaa i veliinupotronje, daljnjem irenju potronje pogodovat ei sve vei zahtjevi za energetskom racionalnou,uinkovitou i ekolokom uvjetovanou.

Evaluations of uctuations of natural gas pricesremained in the shadow of the evaluations of uc-tuations of oil prices exactly because of the factthat natural gas prices in international trade andexchange directly depend on oil prices(oil derivati -ves prices ). In particular, they depend on the priceof low-sulphur fuel oil as the oil derivative. Prices

of energy sources in general need to be interrela-ted in order to use the measures of economic po-litics to direct the consumption of those sources,exactly by virtue of those prices, depending on thegoals of the given economic politics. Such chan-ges can only be caused by main world consumersand/or main world producers of energy sources.

A slight strengthening of natural gas prices towar-ds oil prices can be expected because of the effectof a number of factors on the growth of demandfor natural gas in the following years. Further de-mand expansion will be favoured by not only the

already constructed transport infrastructure(gaspipelines), great numbers of consumers and theextent of consumption, but also by increasing de-mand for energetic rationality, ef ciency and eco-logical conditions.

8/13/2019 Energy 0901

25/104


LITERATURA / REFERENCESReuters www.reuters.com[1]Bloomberg www.bloomberg.com[2]Standard & Poors www.standardandpoors.com[3]

Authors Adresses:

Nikica Grubii, [email protected] Oil Industry, plcAvenija V. Holjevca 1010000 ZagrebCroatia

Manuscript received:2009-01-21

Accepted:2009-01-31

Adrese autora:

Mr. sc. Nikica [email protected]

INA Industrija nafte d.d.Avenija V. Holjevca 10

10000 ZagrebHrvatska

Urednitvo primilo rukopis:2009-01-21

Prihvaeno:2009-01-31

8/13/2019 Energy 0901

26/104

26Klepo, M., Mikulii, V., imi, Z., Model proizvodne jedinice , Energija, god. 58(2009 ), br. 1., str. 26-55Klepo, M., Mikulii, V., imi, Z., Production Unit Model , Energija, vol. 58(2009 ), No. 1, pp. 26-55

MODEL PROIZVODNEJEDINICE S UKLJUENIM

UVJETIMA OKOLINE U MODELPOUZDANOSTI I RASPOLOIVOSELEKTROENEGETSKOG SUSTAVA

POWER PLANT MODEL WITHENVIRONMENTAL CONDITION

INCLUDED IN THE ELECTRICPOWER SYSTEM RELIABILITYAND AVAILABILITY MODE

Mio Klepo Vladimir Mikulii Zdenko imi, Zagreb, HrvatskaU radu se izlau rezultati teorijsko-metodoloke razrade modela kojim se proizvodne

jedinice, na iji rad, odnosno pogonske osobine, a time i raspoloivost i pouzdanost utjeestanje okoline, najee nepovoljne atmosferske prilike, ukljuuju u modele za izraunpouzdanosti i raspoloivosti elektroenergetskog sustava pri operativnim planiranjima

njegova rada. Model proizvodne jedinice s ukljuenim uvjetima okoline pokraj ovisnosti ovremenu u izraun pokazatelja pouzdanosti i raspoloivosti elektroenergetskog sustava

uvodi i ovisnost o uvjetima okoline u kojima se jedinica nalazi tijekom vremena izloenostitim uvjetima.

This work presents the results of the theoretical-methodological elaboration of themodel by virtue of which the generating units are included in the models for calculation

of reliability and availability of the electric power system in the operative plans of itsoperation. The operation, that is, the operative features of these generating units,

and therewith also their reliability and availability, are in uenced by the state of theenvironment, mostly by adverse weather conditions. The generating units model withenvironmental conditions included also introduces into the calculation of indicators of

the electric power system reliability and availability, along with the time dependence, thedependence on the environmental conditions which the unit is exposed to during duration

of the period of such conditions.

Kljune rijei: dvoparametarski model proizvodne jedinice; model pouzdanosti iraspoloivosti sustava; uvjeti stanja okoline; utjecaj okoline na stanje proizvodne

jediniceKey words: double-parameter generating unit model; system reliability and

availability model; environmental state conditions; environmental impact on thestate of the generating units

8/13/2019 Energy 0901

27/104

8/13/2019 Energy 0901

28/104

Klepo, M., Mikulii, V., imi, Z., Model proizvodne jedinice , Energija, god. 58(2009 ), br. 1., str. 26-55Klepo, M., Mikulii, V., imi, Z., Production Unit Model , Energija, vol. 58(2009 ), No. 1, pp. 26-55 28

1 UVOD

Opi problem prikupljanja podataka, statistikeobrade i izrauna parametara i pokazatelja zauspostavu modela proizvodnih jedinica pri ope-rativnim planiranjima pogona, te naina pristu-pa i rjeenja problema ukljuivanja proizvodnih jedinica u model pouzdanosti i raspoloivostielektroenergetskog sustava, do sada su detalj-nije obraeni i izloeni u vie radova [1] do [14].Ovaj rad uvodi uvjete, odnosno stanje okolinekao parametra koji kada prijee odreenu razi-nu nepovoljnog utjecaja, ili zbog odreenih teh-niko-tehnolokih rjeenja proizvodnih jedinica,utjee na stanje raspoloivosti i pouzdanostiproizvodne jedinice, a time i raspoloivosti i po-uzdanosti elektroenergetskog sustava u cjelini.Uvjeti okoline mogu imati utjecaja na samo jed-no proizvodno postrojenje, ali i vie njih ako seradi o nepovoljnim atmosferskim prilikama kojezahvaaju ili djeluju na velikom podruju. Ipak,pretpostavlja se da je iznimno niska vjerojatnostda nepovoljne atmosferske prilike istodobno za-hvate i nepovoljno utjeu na veliki broj ili pak sveproizvodne objekte elektroenergetskog sustava.

Pod uvjetima okoline kod elektroenergetskihpostrojenja najee se podrazumijevaju atmos-ferske prilike koje ih okruuju. Velik dio opreme,odnosno postrojenja elektroenergetskog susta-va, zatien je, tj. izoliran od nepovoljnih utje-caja okoline, pogotovo atmosferskih prilika, paza njih s velikom tonou vrijedi pretpostavkao konstantnosti uestalosti prijelaza iz stanja ustanje, bez obzira na stanje okoline. Pogotovo tovrijedi za proizvodna i ostala postrojenja smje-tena u zgradama, podzemnim prostorijama isl. Meutim, kako su postrojenja pokraj svih za-tita, a osobito kada tih zatita nema, za vrijemeolujnog vremena, grmljavine, padalina s jakimvjetrom, i sl., vrlo esto izloena nepovoljnimutjecajima, pretpostavka o konstantnoj uesta-losti kvara nije vie odriva kada ti nepovoljniutjecaji prijeu odreenu razinu.

2 MODEL JEDNE JEDINICES UKLJUENIM UVJETIMAOKOLINE2.1 Jednostavni model proizvodne jedinice- model bazne jedinice

Model jedinice s dva stanja(slika 1 ) detaljno jeobraen i izloen u [2], [10] i [12]. To je ujedno inajee koriteni model budui da pokraj jed-nostavnosti i potrebnog malog broja podatakanajbolje aproksimira neprekidan rad jedinicekoja pokriva bazni dio dijagrama optereenja.

1 INTRODUCTION

So far, the general problem of data collection, stati-stical analyses and calculations of parameters andindicators for the establishment of the generatingunit models in operational planning, and the ma-nner of approaching and solving problems of inclusi-on of generating units into the electric power systemreliability and availability model have been analyzedin more detail and presented in several works [1] to[14]. This work introduces conditions, that is, stateof the environment as the parameter which, whenit passes the level of adverse impact, or, due to cer-tain technical-technological solutions of generatingunits, impacts the state of availability and reliabilityof the generating unit, and therewith the availabilityand reliability of the electric power system as a who-le. Environmental conditions can impact only onegenerating plant, but also more of them if adverseweather conditions are such that they encompass oraffect a wide territory. Still, it is presumed that theprobability that adverse atmospheric conditions willsimultaneously encompass and negatively impact alarge number, or possibly even all the production fa-cilities of the electric power system, is quite low.

The environmental conditions in electric powerplants mostly mean atmospheric conditions whichsurround it. A large portion of the equipment, thatis, of the electric power system plant, is protected,that is, insulated from adverse environmental im-pacts, atmospheric conditions especially, so theassumption of the constancy of the rate of transitionfrom state to state applies to that portion with greataccuracy, regardless of the state of the environment.This applies especially to production and all otherplants located in the buildings, underground rooms,etc. However, as the plants, with all the protectionsand even when there are no protections, during stor-my weather, thunder, rainfall with heavy winds, etc.,are very often exposed to adverse conditions, theassumption on the constancy of the failure rate isno longer sustainable when those impacts exceed acertain level.

2 THE MODEL OF A UNIT WITHENVIRONMENTAL CONDITIONSINCLUDED2.1 Simple generating unit model - basic unitmodel

The unit model with two states(Figure 1) is analyzedin detail and presented in [2], [10] and [12]. This isalso the most frequently used model because withthe simplicity and small amount of data necessaryit approximates best the perpetual operation of theunit covering the basic part of the load diagram.

8/13/2019 Energy 0901

29/104

Klepo, M., Mikulii, V., imi, Z., Model proizvodne jedinice , Energija, god. 58(2009 ), br. 1., str. 26-55Klepo, M., Mikulii, V., imi, Z., Production Unit Model , Energija, vol. 58(2009 ), No. 1, pp. 26-5529

unavailability N (t ):

The transient part of the availability function gra-vitates towards zero very soon, and the moment intime when the transient part of the function can be

neraspoloivost N (t ):

Prijelazni dio funkcije raspoloivosti vrlo brzo tei knuli, a vremenski trenutak kada se moe zanema-riti prijelazni dio funkcije u odnosu na stacionarni

Sustav linearnih diferencijalnih jednadbi kojimase opisuje Markovljev proces prema tom jedno-stavnom modelu u opem obliku glasi:

The system of linear differential equations whichdescribes the Markov process according to thatsimple model in the general form reads:

),()()(

),()()(

t P t P t P

t P t P t P

001

100

=

+=(1)

(2)

(3)

(4)

(5)

gdje je:

)(t P i

t t P i

d)(d

derivacija vjerojatnosti stanjai povremenut ,

)(t P i vjerojatnost stanjai (i = 0, 1, 2, ..., n).

Uz pretpostavku da je ut = 0 jedinica u ispravnomstanju, poetni uvjeti glase:

where it is as follows:

)(t P i

t t P i

d)(d derivation of the probability of the

state i per timet ,)(t P i probability of the statei (i = 0, 1, 2, ..., n)

With the assumption that int = 0 the unit is in so-und condition, the initial conditions read:

.)(

,)(

00

10

1

0

==

P

P

U svakom trenutku mora biti ispunjen uvjet da seproizvodna jedinica mora nalaziti u jednom od sta-nja u prostoru stanja, tako da jednadba identitetaglasi:

At all times the condition that the generating unitmust be in one of the states in the state spacemust be ful lled, so that the identity equation re-ads:

110 =+ )()( t P t P .

,

.

Gornji sustav linearnih diferencijalnih jednadbiuz poetne uvjete(2) ima sljedee rjeenje:

raspoloivost A(t ):

The above system of linear differential equations withthe initial conditions(2) has the following solution:

availability A(t ):

t t P t A )(e)()( ++++== 0

t t P t N )(e)()( ++

+

== 1

8/13/2019 Energy 0901

30/104


dio ovisi o veliini uestalosti popravka . Ope-nito, moe se uzeti da prijelazno stanje zavravanakon vremenan = t ( + ) = 4, ( t +=

4).

Prijelazno stanje zavrava i prije ukoliko je > ,to je kod proizvodnih jedinica elektroenergetskogsustava redovito ispunjeno. Zbog toga se u svim

praktinim proraunima koriste izrazi za stacio-narne vrijednosti raspoloivosti i neraspoloivosti, jer se uz zanemarivu pogreku postie znatno po- jednostavljenje prorauna. Svi daljnji prorauni uovom radu bit e vezani i odnosit e se na staci-onarne vrijednosti raspoloivosti, odnosno neras-poloivosti opeg oblika:

disregarded in relation to the steady part dependson the repair rate . In general, it can be assu-med that the transient state ends after the timen = t ( + ) = 4, ( t

+=

4).

The transient state ends even before in case of > ,which is regularly the case with electric power

generating units. Because of that, in all practicalcalculations, expressions for steady values of ava-ilability and unavailability are used because, withnegligible error level, a signi cant simpli cation ofthe calculation is obtained. All further calculationsin this work will be connected and will relate to thesteady values of the availability, that is, unavailabi-lity in the general form:

(6)

(7)

,

.

.

,

,

,

)()(lim =+

==

At A P t

0

)()(lim =+

==

N t N P t

1

Pritom u svakom trenutku mora biti ispunjenosnovni uvjet iz jednadbe identiteta:

Thereat, the basic condition from the identity equ-ation must be ful lled at all times.

(8)

(9)

(10)

(11)

( ) ( ) 1=+ t N t A

Izraz za raspoloivost jedinice moe se napisati iu obliku:

The expression for unit availability can also be wri-tten in the form:

A +=+

= 111

1...)(

to kod visokoraspoloivih jedinica predstavlja vrlodobru aproksimaciju raspoloivosti.

Parametri modela bazne jedinice u stacionarnomstanju mogu se izraunati iz podataka o pogonu jedne ili vie jedinica tijekom dueg vremenskogperioda. Tako, uvaavajui podatke o stanjima ipokazateljima pogonskih stanja proizvodne jedi-nice([10] i [12]), procijenjene ili izraunate vrijed-nosti ulaznih parametara za model bazne jedinice(slika 1 ) jesu:

and this, in highly-available units, represents verygood availability approximation.

Parameters of the steady state basic unit modelcan be calculated based on the data on the driveof one or more units through a longer period oftime. Thus, taking into consideration the data onthe states and indicators of the driving states ofgenerating units([10] i [12]), the estimated or cal-culated values of input parameters for the basicunit model(Figure 1) are:

SK N =

SP N =

8/13/2019 Energy 0901

31/104

Klepo, M., Mikulii, V., imi, Z., Model proizvodne jedinice , Energija, god. 58(2009 ), br. 1., str. 26-55Klepo, M., Mikulii, V., imi, Z., Production Unit Model , Energija, vol. 58(2009 ), No. 1, pp. 26-5531

(12)

(13)

,

,

SP SK SP

SP N

SK N

SK N

P +

=+

=0

SP SK SK

SP N

SK N

SP N

P +=+=1

gdje je:

procijenjena ili izraunata vrijednost ue-stalosti kvara jedinice,

procijenjena ili izraunata vrijednost ue-stalosti popravka jedinice,

i P procijenjena vrijednost vjerojatnosti stanjakomponente ili sustavai (i = 0, 1, 2, ..., n),

N broj dogaaja,SK broj sati ispada iz pogona,SP broj sati pogona.

where it is as follows:

estimated or calculated value of unit failurerate,

estimated or calculated value of unit repairrate,

i P estimated value of the probability of the state ofthe component or the systemi (i = 0, 1, 2, ..., n),

N number of occurrences,SK number of hours of outage,SP number of driving hours.

Slika 1 Shema jednostavnog modela proizvodne jedinice - model bazne jediniceFigure 1 Scheme of the simple production unit model - basic unit model

Oznake:

"0" stanje spremnosti jedinice za pogon,"1" stanje nespremnosti jedinice za pogon,

uestalost kvara jedinice, uestalost popravka jedinice.

Oito je da raspoloivost, odnosno neraspoloivost jedinice prema izrazima(12) i (13) ne ovise o broju ispada iz pogona, tako da se njihove vrijednostimogu procijeniti direktno iz vremena ostajanja ilizadravanja u pojedinim stanjima tijekom proma-tranog vremenskog intervala. U modelu dva stanjavrijeme odravanja uvijek se iskljuuje iz odreiva-nja rizika ispada iz pogona.

Izraz(13) najee se naziva rizikom ispada iz po-gona(engl.Forced Outage Rate FOR) i predstavljaprocjenu vjerojatnosti ispada iz pogona u bilo kojemsluajno odabranom trenutku. Kvaliteta te procjenenajvie ovisi o tipu pogona, tako da statistika pogon-skih podataka mora ukljuivati i vrstu pogona. Todalje znai da bi primjena tog jednostavnog modela

Symbols:

"0" unit operation condition,"1" unit non-operation condition,

rate of unit failure, rate of unit repair.

It is obvious that availability, that is, unavailabilityof the unit according to the expressions(12) and(13) do not depend on the number of outages, sothat their values can be estimated directly basedon the time of abiding or staying in certain statesduring the observed time interval. In the two-state model, the maintenance time is alwaysexcluded from the determination of the outagerisk.

Expression(13) is most usually called ForcedOutage Rate and it represents the estimate ofthe probability of outage at any randomly chosenmoment. The quality of such estimate mostlydepends on the type of drive, so that the statisti-cs of drive data must include the type of drive as

8/13/2019 Energy 0901

32/104


kod jedinica koje rade u vrnom dijelu dijagra-ma optereenja, jedinica koje se ee ukljuuju i iskljuuju iz pogona(cikliki rad), jedinica urezervi ili pripravnosti za pogon, tj. u svim uvjeti-ma koji ne znae kontinuiran pogon pod optere-enjem, dovela do neadekvatne procjene rizikaispada iz pogona.

Meutim, vrlo esto neraspoloivost odgovara- juih podataka o pogonu proizvodnih postrojenjapotrebnih da bi se izraunalo parametre sloe-nijih modela uvjetuje primjenu upravo tog jed-nostavnog modela dva stanja, bez obzira to sepogon znatno razlikuje od konstantnog. Jedanod naina da se smanje problemi i netonostiprimjene modela dva stanja koji pritom nastaju jest da se iz promatranja iskljue trajanja pri-pravnosti jedinice za pogon ili stanja rezerve. Utom sluaju sati ispada iz pogona reduciraju sesamo na sate ispada iz pogona tijekom vremena

potrebe za pogonom. Parametri prema izrazi-ma (10) i (11) raunaju se bez sati rezervnog is-kljuenja. Izraz za rizik ispada iz pogona dobivanovi oblik:

well. Furthermore, this means that the applicationof that simple model in units working in the peakpart of the load diagram, units which go on and offfrom operation more often(cyclic operation), units instandby or state of operation condition, that is, in allthe conditions which do not mean a continued ope-ration under load, would bring about an inadequate

assessment of outage risk.However, very often the unavailability of adequatedata on the drives of the generating plants neces-sary for the calculation of the parameters of morecomplex models conditions the application of exactlythat simple two-state model, regardless of the factthat the drive is signi cantly different from the con-stant one. One of the ways to decrease the extent ofthe problems and the inaccuracies in the applicationof the two-state model wh

energy 0901

Documents