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The nuclear energy alternative in Arab countries
Energy Vol. 13, No. 12, pp. 871-882, 1988 Printed in Great Britain. All tights reserved
THE NUCLEAR
0360~5442/88 $3.00 + 0.00 Copyright @ 1988 PergamonPressplc
ENERGY ALTERNATIVE COUNTRIES
IN ARAB
HASSAN E. S. FATH Faculty of Engineering, Alexandria University, Alexandria, Egypt
and HAMEED H. HASHEM Institute of Technology, Baghdad, Iraq (Received 9 July 1987; received for publication 26 April 1988)
Abstrad-A general survey is presented of energy supplies in the Arab countries. Technologies to exploit nuclear resources are needed in order to ensure a secure energy future. The advantages of introducing nuclear energy into the Arab countries are discussed. The main features of the CANDU (Canada deuterium-uranium) reactors are presented with an assessment concerning their suitability for energy supplies and developing programs. The main differences between the CANDU and PWR (pressurized water reactor) are highlighted.
INTRODUCTION The Arab
countries must implement industrial development to improve living standards. This goal necessitates the transfer of technology from industrial countries in different spheres of technical, educational and training activities. Energy is the backbone of such technology transfer and a key part of the economical, social and educational plan. The objective of any future energy program should not only be aimed at satisfying energy requirements but also at strengthening the capabilities of the Arab countries to develop their diverse energy plans and to integrate energy-sector development with the rest of their economies. We present a general survey of the energy status, along with a recommendation for adopting nuclear energy as a promising energy alternative. Emphasis is placed on CANDU as a suitable technology for transfer to the Arab countries.
ENERGY
STATUS
OF THE
ARAB
COUNTRIES
The present source for electric power production in the Arab countries is mostly fossil fuels, as in most of the rest of the world (Fig. l).’ The availability of fossil fuels and technology in the world market, the ease and safety of fuel handling, and the flexibility derived from small unit sixes are the main reasons for this choice. Table 1 presents Arab energy production, consumption and installed electrical energy capacity and production.’ Compared to the rest of the world (Fig. 2), it is clear that, while the Arab countries produce about 20% of the world crude oil and about 7% of natural gas, they consumed only about 1.7% in 1981 and 2% in 1984 of these supplies. The consumption figure for electric power is lower still, only 1.5%. Table 2 shows the estimated reserves of oil, natural gas, and coal, while Fig. 3 shows these values compared to the rest of the world.3*4 These values show very little coal; however, this deficiency is compensated by an abundance of oil. The relatively high energy production is mainly exported to high-consumption areas. Looking at the energy map of the Arab countries, the most serious problem is the uneven distribution of energy between the Arab countries themselves. It is therefore recommended that the production rates should be reviewed and adjusted to suit their future energy plans. In addition, because of the fact that energy resources are not equally distributed and are limited in some Arab countries, it is important to prepare an energy policy that takes into account the needs of these resource-poor countries. The potential for development of renewable energy sources exists in many Arab countries. 871
HASSANE. S. FATHand HAMEEDH. HASHEM
872
(a)Arob
world
Lb) European
countries
Fig. 1. Sources of electrical power production in 1983.
Table 1. Energy production and consumption of the Arab countries in 1984; TOE = tons of oil equivalent.
Country
Total energy production
Total energy consumption,
lo6
lo6
TOE
TOE
18.03 4.02 24.20 11.90 2.55 7.97 2.90 8.37 0.54 4.44 1.93 4.54 14.00 0.34 6.24 7.68 3.58 10.92 1.40 0.83
Installed electrical energy capacity MW 2,860 997 6,130 3,922 632 5,148 870 2.959 85 1.709 -734 1,383 10,704 113 328 2.517 1,203 1,805 767 158
Lebanon Libya Mauritania Morocco Oman Qatar Saudi Arabia Somalia Sudan Syria Tunisia United A.E. Yemen Yemen 0.
107.53 6.52 50.00 76.70 ___ 65.00 0.27 62.20 ___ 0.64 24.76 19.70 191.65 -__ 0.19 9.20 6.50 75.16 ___ ___
Total
687.02
136.37
45.024
Uor Id
1102.00
i494.00
2251,200
Algeria Bahrain Egypt Iraq Jordan Kuwait
9L
8.48
2.1
2.0
Electrical
Per capita electricity consumption
lo3 HWh
kWh
energy production
8,007 1,986 25,879 16,250 1,918 11,774 2,570 7,716 145 5,950 970 3,236 31,177 172 994 6,208 2,760 8,784 716 514 137,726 9100,000 1.5
356 5,150 592 1,144 764 7,983 988 2,411 2;: 881 14,088 3,117 38 7:: 412 7,985 104 257 790
Ave.= Ave.=2000
39.5
The nuclear energy alternative in Arab countries
(1 i Crude
011
(2) (a)
Natural
gas
1981 x IO6
(3)
Arab world 1.5 %
TOE
cm1
Production
Chlna 7 3%
6161.7
873
6499
1984 x 106
Arob
1983 Production power 91M) TWh
TOE
(b) Consumption
world
1983 Installed copac~fy
(~1
1983 Per capita 2000 kWh
Electricity
Fig. 2. Energy in the Arab countries as compared to the rest of the world.‘,’
Table 2. Estimated reserves of fossil fuels in the Arab countries.3’4 Crude
lgeria ahrain 9YPt raq
ordan uwait ebanon ibya auritania orocco man atar audi Arabia omalia udan yria unisia nited A.E. emen A. emen II.
0.806 0.858 0.869 0.846
___ 0.867 __0.831 --0.830 0.860 0.830 0.852 ___ ___ 0.906 0.820 0.840 __--_
otal
-__
orld
_-%
___
8.80 0.16 3.90 65.00 ___ 92.50 ___ 21.30 ___ ___ 4.00 3.30 171.50 ___ ___ 1.40 1.80 33.00 __--_
Oil
Natural Gas
32.00 e2.12 44.00 72.00 -__ 51.40 ___ 52.30 ___ 2Kl 15:oo 168.40 _____ 8.20 6.00 60.70 ___ ___
9,450 9,320 9,320 9,320 ___ 9,320 ___ 9,320 __9,320 8,675 9,320 9,320 ___
___ 9,320 11,000 9,320 ___ ___
3,033 201 200 921 ___ 1,037 ___ 606 ___ -__ 170 4,193 3,544 ___ -_35
119 929 _-_--
Coal
93,821 5,547 4,007 4.900 ___ 5,814 ___ 12,350 __50 ___ 5,960 29.050 ___ --_ 506 510 18,030 ___ --_
--_ l--_ __--_ --_
30.0 ___ 35.3 ___ ___
--_ --_ --_ ---
___ ___ --_ --_
448 -----
35.8 ___ ___
-----_----r--L --_ -------
488
1
2.9 ___ _--
(
-__
104.0
HASAN E. S. FATH and HAMEED H. HASHEM
874
U.S. A 3 8 %
billion barrels)
(721
U S A.,
U.S.S.R , Chlno
Arab
world
0.015%
(688 Fig. 3. Reserves
of fossil fuels in the Arab countries
billion
tons)
as compared
to the world as a whole.
At present, with the exception of hydroelectric power, most of these sources can be tapped only for producing small quantities of power for local use. But the technology is changing and it may one day be possible to produce large amounts of power from the sun and the wind. Hydroelectric power is the most reliable renewable energy source for producing large amounts of electrical power. The potential of hydroelectric power has not been fully exploited in the Arab countries. The higher capital cost and the lack of sources near consumption centres may be the main constraints. The Arab development of hydroelectric energy up to 1984 indicates that it represents about 1% of the world value. Almost no new projects have been installed since 1980 and the total hydroelectric energy production is unchanged. Sunlight is a promising future energy source for the world, in general, and for the Arab countries, in particular, because most of these countries are located in the sun belt. Although large solar power generation is not economical at present, technology is available for utilizing solar energy for domestic purposes such as water and space heating and cooling, agriculture, and water desalination. The latter can also be done on an industrial scale. There were new solar energy projects in the Arab countries in 1985. A 500 m3/day multistage, flash water-desalination plant came on stream in the United Arab Emirates; a 156-unit residential complex fitted with 4892 solar heaters and with a 7-ton cooling unit for each residential unit was opened in Baghdad; a 25 kW project to light 13 classrooms in a school was initiated in Kuwait; several villages were supplied with solar-generated electricity in Algeria, Morocco, Tunisia, Libya, and Mauritania.
The nuclear energy alternative in Arab countries
875
Wind energy has been used in the Arab countries since ancient times to operate windmills and sail boats. The mean annual wind velocity in the Arab region varies between 3 and 5 m/set, which is adequate for running windmills. Wind energy can be used for pumping water and other agro-industrial purposes, particularly in remote areas. The two main problems associated with solar and wind energies are their unsteady supply-patterns and storage difficulty. The few small wind-power units installed in the Arab countries are still experimental and designed mainly for pumping water. For example, the two biggest units in Jordan can each pump 100 m3 of water per day and generate 1 kW of electricity. Tunisia has a small unit, and Syria is building a unit near Horns and some small units near Qalamum. Agricultural wastes may become important supply sources if simple and cheap furnaces are designed and made available to the general public. Some of these systems have been in use for a long time and only limited updating is required. Morocco, Sudan, Egypt, Tunisia, and other Arab countries are studying means for producing synthetic gas. Some digesters were manufactured in 1983, in Morocco, but their capacity was limited to 2 m3. The use of biomass remains widespread in remote, rural areas of many Arab countries. Finally, animal and human muscles are contributors. Development of small, convenient devices for the efficient utilization of the human muscle output and improved breeding programs to develop better work animals that can survive on local produce will greatly reduce the dependence on other energy sources. For the development of some of these energy resources, all that is needed is increased awareness of what is available and some local ingenuity to tap them. A general improvement of the basic technical skills of the entire population is required.
NUCLEAR
ENERGY
IN THE
ARAB
COUNTRIES
A forecast for energy-consumption growth in the Arab countries is shown in Tables 3 and 4. Figure 4 shows the expected electrical energy production and installed capacity up to the year 2000.6 Electric power production by burning fossil fuels may seem to be an easy solution for now. However, for the long term, other alternatives have to be considered. Reviewing energy resources, nuclear energy seems to be the promising alternative for the future for both the
Table 3. Energy-consumption
r Country
Algeria Bahrain Egypt Iraq Jordan Kuwait Lebanon Libya Mauritania Moroco
Oman Qatar Saudi Arabia Somalia Sudan Syria Tunisia United A.E. Yemen A. Yemen D. Total
growth (lo3 TOE).6
1
Years 1990
23,986 4,155 28,139 21,351 4,155 8,992 1,100 11,800 300 7,811 2,518 5,781 39,200 881 1,932 10,015 5,262 7,918 1,511 1,221 188,628
1955 38,448 4,981 36,624 29,762 6,098 10.549 1,500 15,499 1,450 10,386 3,764 6,580 48,089 1,485 2,333 14,507 7,207 10,592 1.619 1.326 252.?99
2000 54.759 6,056 47,437 39,264 8,669 12,751 2,300 20,702 2,100 13,967 5,517 7,121 65,760 1,708 2,439 21,014 100,052 13,967 2,328 1,854 339,765
HASSANE. S. FATH and HAMEEDH. HASHEM Table 4. Forecast of the share of energy sourcesin the years 1995 and 2000 for the Arab countries.
Country
r
X of total enerav consumption (1995)_‘ l-
!Hural
Oil Algeria Bahrain Egypt
Iraq Jordan Kuwait Libya Morocco Oman Qatar Saudi Arabia Syria Tunisia United A.E. YemenD. Other Countries Total
iydro Coal
Sac 1.2 _-_
36.0 44.0 76.1 68.0 98.4 52.0 76.0 89.8 74.0 14.0 80.0 87.2 79.0 70.0 100.0 94.6
61.0 56.0
0.5 _--
2::: _-_ 47.4 24.0 ___ 26.0 36.0 19.0 1 .a 19.4 30.0 ___ ___
::: _-_-_-4.8 _-_-_-_ 6.9 0.2 _-_-5.4
1.3 ___ 3.7 ___ ___ _-___ 5.4 _-_-_-_ 0.1 -__ _--__ ___
96.0
26.0
2.6
1.0
X of total enerqv consumption Hydro
:oal
Solar +Nucl.
1.2 __3.5 -________
4.0 1.4 ___ _-_ _-_
z!-: 78:a 91.2 76.0 16.0 79.1 86.0 83.9 71.0 100.0 100.0
27.3 ___ 44.0 18.6 ___ 24.0 84.0 19.4 1.4 14.0 29.0 --_ --_
0.4 -_7.3 5.1 -_-____ 4.3 _-_ -_-_5.5 0.2 ______-
4.5 ________________-
2.1 _-_ 5.2 3.8 2.0 1.0 2.6 _-_-_-_ ___ 7.1 1.9 -__ ___ __-
1.4
68.9
25.4
2.3
0.9
2.5
23:; ::: ___ _-_ ___ _-1.0
Oil 36.3 50.0 75.0 63.8
Nabgal 60.0 50.0 9.0
1
and the Arab countries. The uranium resources of the Arab countries are shown in Table 5. Uranium resources are concentrated in Algeria and Somalia. The known reserves of thorium deposits are mostly in Egypt and amount to 15,000280,ooO tons.’ It is important to remember that uranium and thorium may be used to produce Pu-239 and U-233 which are weapon-grade materials. For this reason data related to applications of these fuels are not freely available. Arab North African countries are particularly rich in phosphate deposits and almost all of these deposits contain from 0.1 to 0.2% of uranium. The uranium is extracted as a by-product. Arab phosphate production and reserves are given in Table 6. The introduction and growth of nuclear power in the Arab countries has been slow. As skilled manpower becomes available in countries such as Syria, Algeria, Egypt, and Iraq, it may become possible to exploit this new technology over the next few decades. The unified electrical networks of some of the Arab countries are capable of accommodating nuclear power plants of 200400 MWe, while Egypt can accommodate plants of 600-1200 MWe. A study by the International Atomic Energy Agency has shown that eight Arab countries are in a position to introduce nuclear energy by the year 1990.’ Algeria has followed an independent line towards developing uranium processing and fuel fabrication. The Algerian program favours indiginous growth of reactor technology to enable them to build their own reactor.’ Egypt has world
$j WT
0
90 6.
t
eZa
Insrolled
f359
Production
cop(IciTy power
z
70
C:: 0
60
300
lg
50
250
x 0 2
40
200
‘5 n e 0
30
150
5
20
100
=
10
50
La P g w
Years Fig. 4. Expected electrical energy production and installed capacity in the Arab countries.
The nuclear energy alternative in Arab countries
877
Table 5. Uranium reserves in Arab countries.
r
Country
I
Lkaniun researves, lo3 Tons 26.40 6.57 0.04 1.65 12.50
Algeria Egypt Morocco Sudan Somalia
I
Total
I
47.16
Table 6(a). Uranium as a by-product of phosphate in the Arab countries--phosphate production. Production of phosphate
Country
lo6
tons
Aver age uranium concentration
Extractable U30s in 1984, tons
DDm 0.946
0.708 0.363 4.390 17.094 1.460 4.730
100 90 75 120 120 100 50
27 526 2,050 146 236
3,142
29.700
~ 124.600
I
I
12,460
100
25.2
23
~
Table 6(b). Uranium as a by-product of phosphate in the Arab countriesphosphate reserves. Reserves
Total
Low
High
Ave.
Reasonably assured uranium in phosphate, reserves, tons
95 70 ___ 90
120 120 ___ 180
20,500 47,700 32,400 124,680 6.840.000 ___ -__ 62,400 39,750
of phosphate
lo6 tons
Country
Uranium concentration DPln -
Algeria Egypt Iraq Jordan Morocco Mauritania Saudi labia Syria Tunisia
205 530 432 1039 57000 ___ ___ 624 795
--624 --502 --100 190 235 ---
205 1154 432 1541 57000 ;: 859 795
G -__ 30 40
250 130 ___ 200 90
100 90 75 120 120 100 ___ 100 50
Total
60785
1651
62276
___
___
___
7,167.430
World
1300000
---
___
___
___
-__
13.000.000
1 ---
___
___
___
___
‘IL
47
55.1
HASSANE. S. FATHand HAMEEDH. HASHEM
878
2-MWe research reactor of Soviet design. During the last few years, Egypt has gone through several cycles of announcing the intent to build nuclear power plants with help of the U.S.A., France, Germany or Canada. Electricite de France (EdF) announced that the utility would be negotiating the Egypt contract as a turnkey operation, which will lead to two 900 MWe plants. On the other hand, the outcome of talks between Egypt and Canada is an agreement on nuclear cooperation, exchange of information, technology transfer, and supply of nuclear equipments and materials.’ Iraq also a 2 MWe research reactor similar to that of Egypt. This plant was built in 1968 with assistance from the U.S.S.R. Recently, Iraq has signed cooperation agreements with France and Italy for the supply of a high-flux 70-MWe research reactor. This reactor was destroyed by Israel in 1981. Iraq has also been negotiating with France for the supply of a 900-MWe reactor and more recently, with the U.S.S.R. for a 440-MWe reactor. As the result of the present Iraq-Iran war and the Israeli attack, the Iraqi program may be delayed.’ Syrian and Libyan plans are still at the negotiating stage with the U.S.S.R. to supply one 440-MWe reactor to each country.
NUCLEAR
TECHNOLOGY
TRANSFER
A primary contribution of nuclear power to the development of the Arab countries is and training activities. The technology transfer, with associated technical, educational introduction of an integrated technology-transfer plan implies involvement in all aspects of that technology, e.g., nuclear physics, electronics, as well as agricultural, biological, chemical, metallurgical, and other branches of science and technology. Each of these fields requires skilled and professional personnel and covers a broad range of activities, which includes the education of managers of complex organizations, specialist engineers and scientists in high-technology disciplines, graduate engineers and designers, and technicians in many fields who would all be of great help to the development of the Arab countries. The Arab countries already have a fairly large pool of trained manpower to seed the growth of such technology. Without a domestic manufacturing capability of nuclear-plant systems and components, the construction and maintenance of these plants would remain dependent on technology assistance from external suppliers and would therefore deplete foreign-currency reserves. The technology-transfer package should cover the following items: (i) research and development programs for which code development, experimental verifications and component tests are planned; (ii) engineering establishments where reactor systems and components are designed; (iii) fuel-cycle programs including uranium exploration, mining and fuel fabrication; (iv) manufacturing-technology transfer to allow in-house manufacture of reactor components; (v) educational programs in the universities, laboratories, and at reactor sites.
CANDU
AS A SUITABLE
TECHNOLOGY
The CANDU reactor is a pressurized heavy-water reactor (PHWR) fuelled with natural uranium oxide, clad in zirconium alloy. The fuel is loaded into horizontal pressure tubes, which pass through a large tank (the calandria) filled with a heavy-water moderator. Heavy water is used at high pressure as coolant. The CANDU system is fuelled on-load by two remotely operated machines. The fuelling machines simultaneously insert fresh fuel while removing a spent fuel bundle. The general economical, safety, and reliability advantages of the CANDU reactor will be discussed, together with an assessment of its suitability for energy and development programs in the Arab countries. Figure 5 summarizes the socio-economic impact of CANDU technology in the Arab countries.” Natural uranium and fuelsycle
jlexibility
The main advantages of the use of natural uranium in CANDU reactors are the following: (a) it widens the sources of supply and allows easier manufacture. This inexpensive fuel can be fabricated in the Arab countries without the need for enrichment technology. The Canadian
879
The nuclear energy alternative in Arab countries
CANDU reactor
Cheap and plentiful Developments
Decentralization
of the mining industry
;
and of uranium and thorium processing development industry
of capital goods
;
major capital construction
program
development
light
industries advancement
education
1 Indirect
Participation surplus
;
for personal development
for the rural population.
technological
benefits
[
in advanced systems research and development
electrolysis
, industry
.
steam for process
development advanced
and recreation
handicraft
;
such as electronic6 of technical
greater opportunities
;
;
of agriculture
and of small rural/urban
for nuclear components of specialized
of industry
greater productivity
;
electric poser
for hydrogen
fuel/feedstook
of a radiochemical
industry
treatment
facilities
minimizes
refrigeration
production
;
;
applications
Fig. 5. Impact tree of CANDU
;
,
medical
food irradiation
other industrial/educational
(R&D)
;
industries
needs
;
of radioisotopes.
technology transfer to the Arab countries.
companies are willing to share their expertise with countries undertaking a CANDU program.‘l (b) Consumption of natural uranium in the CANDU reactor is about 15% less than that of enriched-fuel reactors over the life of the reactor (see Table 7). (c) The CANDU fuel-cycle system can be developed to accommodate a new fuel cycle as the economic situation dictates. Good neutron economy of the reactor permits exploitation of a self-sufficient thorium fuel-cycle, which requires minor modifications to the reactor and permits the recycling of natural uranium fuel indefinitely with only a small addition of thorium. It should be noted that Egypt is relatively rich in thorium deposits.3 Security of fuel supply is an important factor for economic well being and development, as well as for political independence.
Table 7(a).
Approximate equilibrium fuel consumption.6
Reactor
CANDU
LWR
Fuel consumption kg/W-year
type
(natural uranium through)
(fuelled with uranium)
once
167
enriched
200
Table 7(b). Natural uranium required for 6000 MWe.6 Reactor
First
type
I
charge
I
Year Ly consumption
I
HASSANE.
880
S. FATHand HAMEED H.
HASHEM
The advantage of using pressure tubes
The use of pressure tubes in the reactor core allows the primary coolant system to be pressurized without the need for a massive pressure vessel. The advantage of this approach include the ability of local industry to participate significantly in construction, design, installation, component fabrication, and supply. This aspect has proved to be a primary advantage for developing countries such as Argentina, Korea, Romania, India, and Pakistan. Heavy-water technology
The availability of heavy water is important to operation of the CANDU reactor. Any country that participates in a CANDU program may buy, lease, or manufacture heavy water. Heavy water is uniformly distributed in ordinary light water (one part per 7000) and its production has been developed in Canada, the U.S.S.R., the U.S.A., and other countries. An essential feature of many CANDU proposals is the transfer of heavy-water technology in case the client requires self-sufficiency. The technology-transfer package includes plant siting and environmental-impact studies, plant design, vendor and contract selection, project schedule and cost control, quality-assurance program development, plant-personnel training programs, commissioning and start-up support, and operation support. The heavy water in the CANDU reactor eliminates the need for enriched uranium fuel, which is several orders of magnitude more difficult and expensive to produce than heavy water. In addition, uranium-enrichment technology is not being transferred. Moreover, heavy water is not a consumable item like enriched uranium, except that some of the deuterium is converted to tritium. On-power fueling The CANDU reactor-design arrangement allows use of on-power fuelling. This arrangement has the following advantages: (a) a high capacity factor is achieved because of high availability; Fig. 6 shows the annual load factor for 35 reactors; (b) defective fuel can be removed while reactor operation continues, which minimizes maintenance problems caused by high radiation fields in the reactor-coolant circuit; (c) on-load fuelling leads to optimal reactor-flux patterns and best fuel use; (d) because the CANDU system uses neutrons more efficiently than
Annual 70
75
I
I
load 80 I
factor 85 I
‘/. so I
E
AECL-CANDU KWU - PWR GETSCOBWR AECL - CANDU WestinghousePWR KWU - PWR GE-BWRVariousMAGNDX ACECOWEN -PWRGE- PWR Westmghouae -PWR
_ I_
AECL-CANDUMHI-PWRFramotoma - PWR ASEA-Atom --BWR _ Framatome-PWRGEC-MAGNOXAECL-CANDU Westinghouse -PWRACECOWEN
-
PWR
r-
Siemens -PWR l-1 GC-MAGNOXB ASEA-Atom-8WR_ Westrnahouse - PWR AkL-CANDU MHI-PWRWestinghouse-PWRF Siemens - PWRGE-BWRAECLCANDUEE/BW/TW-MAGNOXWestinghouse - PWR w
Fig. 6. Annual load factors for the top 35 reactors.
95 1
881
The nuclear energy alternative in Arab countries
3000
l
CANDU
multiple
0
Multiple
unit
D Slngk
0
lo
““““““““““’
1970
unit plant
un,t
plant
uA
0
plant
(LWR) L7
(LWt?)
1975 Midpoint
1980 of
in-service
1985
1990
dates
Fig. 7. Capital cost comparisons for CANDU and CWR reactors.
light-water reactors, it requires less uranium for a given electrical output. Accordingly, the fuel for CANDU reactors costs less than 60% of that for a PWR for the same amount of generated heat (see Table 7).‘l
Additional safety advantages of the CANDU
reactor
CANDU has no criticality problem with natural uranium spent fuel stored under water. Repair of fuel channels during the lifetime of a station is relatively easy. However, repair of a faulty pressure vessel is very difficult. The CANDU fuel channels, reactor controls and monitoring devices can be replaced in situ. The pressure tubes have the advantage that any cracks are revealed by leakage, which is easily detected. Breaks in one or several pressure tubes will have less serious consequences than a break in a large pressure vessel. Furthermore, the small diameter of the pressure tubes lowers the maximum potential discharge to containment in the event of a loss-of-coolant accident (LOCA) caused by a pressure-tube break. A serious pressure-tube crack associated with a LOCA was completely controlled and tube replacement was carried out in the Pickering reactor in Canada. The use of pressure tubes allows separation of coolant and moderator, which means that the reactivity-control devices are placed in a low-pressure and low-temperature environment that minimizes the likelihood of failure. Moreover, core melt-down is less likely to occur than in other reactor types because of the presence of three separate and independent heat sinks, namely, emergency core cooling (ECC), moderator, and shield-tank water. CA ND U economy Extensive information from electrical utilities in the U.S.A. and Canada indicates that the dry capital cost (the cost of the facility excluding fuel and heavy water) of a CANDU nuclear generating station is comparable to the dry capital cost of LWR stations (Fig. 7). The cost of the initial charge of heavy water and its replenishment, as required during the life of the plant, is offset by CANDU’s low fuelling cost. Accordingly, CANDU reactors provide the lowest cost for nuclear-generated electricity because of their high capacity factors.
REFERENCES 1. H. El-Khateeb,
“Electricity
in the Arab World,” Third Arab Energy Conference,
Algeria (1985).
2. OAPEC Bulletin, Kuwait (1986). 3. OAPEC, “The Secretary General’s Twelfth Annual Report,” AH 1405/AD, Kuwait (1985). 4. Arab Organisation for Mineral Resources (AOMR) , “Solid Energy Resources in the Arab Countries,”
Third Arab Energy Conference, Algeria (1985). “Biomass Energy in the Arab World,” Third Arab Energy
5. A. A. Shalash, (1985).
Conference,
Algeria
HA~.$ANE.
882 6. I. Ibrahim,
7. 8. 9.
10. 11.
S. FATH and HAMEED H. HASHEM
“Energy Demand and Consumption Forecasts in the Arab Countries,” Third Arab Energy Conference, Algeria (1985). Federal Institute for Geosciences and Natural Resources, “Survey of Energy Resources,” 11th World Energy Conference, Munich (September 1980). K. E. Effat, “Role of Nuclear Energy in the Developing Countries,” Third Arab Energy Conference, Algeria (1985). Nucl. Engng Znt. (January and March 1982). D. S. Lawson,” CANDU to Meet World’s Needs,” AECL-7502 (1981). J. Bouton, “What are the Prospects for CANDU in Mexico,” AECL-Marketing, lecture presented in Mississauga city, Ontario, Canada (May 1982).
THE NUCLEAR
0360~5442/88 $3.00 + 0.00 Copyright @ 1988 PergamonPressplc
ENERGY ALTERNATIVE COUNTRIES
IN ARAB
HASSAN E. S. FATH Faculty of Engineering, Alexandria University, Alexandria, Egypt
and HAMEED H. HASHEM Institute of Technology, Baghdad, Iraq (Received 9 July 1987; received for publication 26 April 1988)
Abstrad-A general survey is presented of energy supplies in the Arab countries. Technologies to exploit nuclear resources are needed in order to ensure a secure energy future. The advantages of introducing nuclear energy into the Arab countries are discussed. The main features of the CANDU (Canada deuterium-uranium) reactors are presented with an assessment concerning their suitability for energy supplies and developing programs. The main differences between the CANDU and PWR (pressurized water reactor) are highlighted.
INTRODUCTION The Arab
countries must implement industrial development to improve living standards. This goal necessitates the transfer of technology from industrial countries in different spheres of technical, educational and training activities. Energy is the backbone of such technology transfer and a key part of the economical, social and educational plan. The objective of any future energy program should not only be aimed at satisfying energy requirements but also at strengthening the capabilities of the Arab countries to develop their diverse energy plans and to integrate energy-sector development with the rest of their economies. We present a general survey of the energy status, along with a recommendation for adopting nuclear energy as a promising energy alternative. Emphasis is placed on CANDU as a suitable technology for transfer to the Arab countries.
ENERGY
STATUS
OF THE
ARAB
COUNTRIES
The present source for electric power production in the Arab countries is mostly fossil fuels, as in most of the rest of the world (Fig. l).’ The availability of fossil fuels and technology in the world market, the ease and safety of fuel handling, and the flexibility derived from small unit sixes are the main reasons for this choice. Table 1 presents Arab energy production, consumption and installed electrical energy capacity and production.’ Compared to the rest of the world (Fig. 2), it is clear that, while the Arab countries produce about 20% of the world crude oil and about 7% of natural gas, they consumed only about 1.7% in 1981 and 2% in 1984 of these supplies. The consumption figure for electric power is lower still, only 1.5%. Table 2 shows the estimated reserves of oil, natural gas, and coal, while Fig. 3 shows these values compared to the rest of the world.3*4 These values show very little coal; however, this deficiency is compensated by an abundance of oil. The relatively high energy production is mainly exported to high-consumption areas. Looking at the energy map of the Arab countries, the most serious problem is the uneven distribution of energy between the Arab countries themselves. It is therefore recommended that the production rates should be reviewed and adjusted to suit their future energy plans. In addition, because of the fact that energy resources are not equally distributed and are limited in some Arab countries, it is important to prepare an energy policy that takes into account the needs of these resource-poor countries. The potential for development of renewable energy sources exists in many Arab countries. 871
HASSANE. S. FATHand HAMEEDH. HASHEM
872
(a)Arob
world
Lb) European
countries
Fig. 1. Sources of electrical power production in 1983.
Table 1. Energy production and consumption of the Arab countries in 1984; TOE = tons of oil equivalent.
Country
Total energy production
Total energy consumption,
lo6
lo6
TOE
TOE
18.03 4.02 24.20 11.90 2.55 7.97 2.90 8.37 0.54 4.44 1.93 4.54 14.00 0.34 6.24 7.68 3.58 10.92 1.40 0.83
Installed electrical energy capacity MW 2,860 997 6,130 3,922 632 5,148 870 2.959 85 1.709 -734 1,383 10,704 113 328 2.517 1,203 1,805 767 158
Lebanon Libya Mauritania Morocco Oman Qatar Saudi Arabia Somalia Sudan Syria Tunisia United A.E. Yemen Yemen 0.
107.53 6.52 50.00 76.70 ___ 65.00 0.27 62.20 ___ 0.64 24.76 19.70 191.65 -__ 0.19 9.20 6.50 75.16 ___ ___
Total
687.02
136.37
45.024
Uor Id
1102.00
i494.00
2251,200
Algeria Bahrain Egypt Iraq Jordan Kuwait
9L
8.48
2.1
2.0
Electrical
Per capita electricity consumption
lo3 HWh
kWh
energy production
8,007 1,986 25,879 16,250 1,918 11,774 2,570 7,716 145 5,950 970 3,236 31,177 172 994 6,208 2,760 8,784 716 514 137,726 9100,000 1.5
356 5,150 592 1,144 764 7,983 988 2,411 2;: 881 14,088 3,117 38 7:: 412 7,985 104 257 790
Ave.= Ave.=2000
39.5
The nuclear energy alternative in Arab countries
(1 i Crude
011
(2) (a)
Natural
gas
1981 x IO6
(3)
Arab world 1.5 %
TOE
cm1
Production
Chlna 7 3%
6161.7
873
6499
1984 x 106
Arob
1983 Production power 91M) TWh
TOE
(b) Consumption
world
1983 Installed copac~fy
(~1
1983 Per capita 2000 kWh
Electricity
Fig. 2. Energy in the Arab countries as compared to the rest of the world.‘,’
Table 2. Estimated reserves of fossil fuels in the Arab countries.3’4 Crude
lgeria ahrain 9YPt raq
ordan uwait ebanon ibya auritania orocco man atar audi Arabia omalia udan yria unisia nited A.E. emen A. emen II.
0.806 0.858 0.869 0.846
___ 0.867 __0.831 --0.830 0.860 0.830 0.852 ___ ___ 0.906 0.820 0.840 __--_
otal
-__
orld
_-%
___
8.80 0.16 3.90 65.00 ___ 92.50 ___ 21.30 ___ ___ 4.00 3.30 171.50 ___ ___ 1.40 1.80 33.00 __--_
Oil
Natural Gas
32.00 e2.12 44.00 72.00 -__ 51.40 ___ 52.30 ___ 2Kl 15:oo 168.40 _____ 8.20 6.00 60.70 ___ ___
9,450 9,320 9,320 9,320 ___ 9,320 ___ 9,320 __9,320 8,675 9,320 9,320 ___
___ 9,320 11,000 9,320 ___ ___
3,033 201 200 921 ___ 1,037 ___ 606 ___ -__ 170 4,193 3,544 ___ -_35
119 929 _-_--
Coal
93,821 5,547 4,007 4.900 ___ 5,814 ___ 12,350 __50 ___ 5,960 29.050 ___ --_ 506 510 18,030 ___ --_
--_ l--_ __--_ --_
30.0 ___ 35.3 ___ ___
--_ --_ --_ ---
___ ___ --_ --_
448 -----
35.8 ___ ___
-----_----r--L --_ -------
488
1
2.9 ___ _--
(
-__
104.0
HASAN E. S. FATH and HAMEED H. HASHEM
874
U.S. A 3 8 %
billion barrels)
(721
U S A.,
U.S.S.R , Chlno
Arab
world
0.015%
(688 Fig. 3. Reserves
of fossil fuels in the Arab countries
billion
tons)
as compared
to the world as a whole.
At present, with the exception of hydroelectric power, most of these sources can be tapped only for producing small quantities of power for local use. But the technology is changing and it may one day be possible to produce large amounts of power from the sun and the wind. Hydroelectric power is the most reliable renewable energy source for producing large amounts of electrical power. The potential of hydroelectric power has not been fully exploited in the Arab countries. The higher capital cost and the lack of sources near consumption centres may be the main constraints. The Arab development of hydroelectric energy up to 1984 indicates that it represents about 1% of the world value. Almost no new projects have been installed since 1980 and the total hydroelectric energy production is unchanged. Sunlight is a promising future energy source for the world, in general, and for the Arab countries, in particular, because most of these countries are located in the sun belt. Although large solar power generation is not economical at present, technology is available for utilizing solar energy for domestic purposes such as water and space heating and cooling, agriculture, and water desalination. The latter can also be done on an industrial scale. There were new solar energy projects in the Arab countries in 1985. A 500 m3/day multistage, flash water-desalination plant came on stream in the United Arab Emirates; a 156-unit residential complex fitted with 4892 solar heaters and with a 7-ton cooling unit for each residential unit was opened in Baghdad; a 25 kW project to light 13 classrooms in a school was initiated in Kuwait; several villages were supplied with solar-generated electricity in Algeria, Morocco, Tunisia, Libya, and Mauritania.
The nuclear energy alternative in Arab countries
875
Wind energy has been used in the Arab countries since ancient times to operate windmills and sail boats. The mean annual wind velocity in the Arab region varies between 3 and 5 m/set, which is adequate for running windmills. Wind energy can be used for pumping water and other agro-industrial purposes, particularly in remote areas. The two main problems associated with solar and wind energies are their unsteady supply-patterns and storage difficulty. The few small wind-power units installed in the Arab countries are still experimental and designed mainly for pumping water. For example, the two biggest units in Jordan can each pump 100 m3 of water per day and generate 1 kW of electricity. Tunisia has a small unit, and Syria is building a unit near Horns and some small units near Qalamum. Agricultural wastes may become important supply sources if simple and cheap furnaces are designed and made available to the general public. Some of these systems have been in use for a long time and only limited updating is required. Morocco, Sudan, Egypt, Tunisia, and other Arab countries are studying means for producing synthetic gas. Some digesters were manufactured in 1983, in Morocco, but their capacity was limited to 2 m3. The use of biomass remains widespread in remote, rural areas of many Arab countries. Finally, animal and human muscles are contributors. Development of small, convenient devices for the efficient utilization of the human muscle output and improved breeding programs to develop better work animals that can survive on local produce will greatly reduce the dependence on other energy sources. For the development of some of these energy resources, all that is needed is increased awareness of what is available and some local ingenuity to tap them. A general improvement of the basic technical skills of the entire population is required.
NUCLEAR
ENERGY
IN THE
ARAB
COUNTRIES
A forecast for energy-consumption growth in the Arab countries is shown in Tables 3 and 4. Figure 4 shows the expected electrical energy production and installed capacity up to the year 2000.6 Electric power production by burning fossil fuels may seem to be an easy solution for now. However, for the long term, other alternatives have to be considered. Reviewing energy resources, nuclear energy seems to be the promising alternative for the future for both the
Table 3. Energy-consumption
r Country
Algeria Bahrain Egypt Iraq Jordan Kuwait Lebanon Libya Mauritania Moroco
Oman Qatar Saudi Arabia Somalia Sudan Syria Tunisia United A.E. Yemen A. Yemen D. Total
growth (lo3 TOE).6
1
Years 1990
23,986 4,155 28,139 21,351 4,155 8,992 1,100 11,800 300 7,811 2,518 5,781 39,200 881 1,932 10,015 5,262 7,918 1,511 1,221 188,628
1955 38,448 4,981 36,624 29,762 6,098 10.549 1,500 15,499 1,450 10,386 3,764 6,580 48,089 1,485 2,333 14,507 7,207 10,592 1.619 1.326 252.?99
2000 54.759 6,056 47,437 39,264 8,669 12,751 2,300 20,702 2,100 13,967 5,517 7,121 65,760 1,708 2,439 21,014 100,052 13,967 2,328 1,854 339,765
HASSANE. S. FATH and HAMEEDH. HASHEM Table 4. Forecast of the share of energy sourcesin the years 1995 and 2000 for the Arab countries.
Country
r
X of total enerav consumption (1995)_‘ l-
!Hural
Oil Algeria Bahrain Egypt
Iraq Jordan Kuwait Libya Morocco Oman Qatar Saudi Arabia Syria Tunisia United A.E. YemenD. Other Countries Total
iydro Coal
Sac 1.2 _-_
36.0 44.0 76.1 68.0 98.4 52.0 76.0 89.8 74.0 14.0 80.0 87.2 79.0 70.0 100.0 94.6
61.0 56.0
0.5 _--
2::: _-_ 47.4 24.0 ___ 26.0 36.0 19.0 1 .a 19.4 30.0 ___ ___
::: _-_-_-4.8 _-_-_-_ 6.9 0.2 _-_-5.4
1.3 ___ 3.7 ___ ___ _-___ 5.4 _-_-_-_ 0.1 -__ _--__ ___
96.0
26.0
2.6
1.0
X of total enerqv consumption Hydro
:oal
Solar +Nucl.
1.2 __3.5 -________
4.0 1.4 ___ _-_ _-_
z!-: 78:a 91.2 76.0 16.0 79.1 86.0 83.9 71.0 100.0 100.0
27.3 ___ 44.0 18.6 ___ 24.0 84.0 19.4 1.4 14.0 29.0 --_ --_
0.4 -_7.3 5.1 -_-____ 4.3 _-_ -_-_5.5 0.2 ______-
4.5 ________________-
2.1 _-_ 5.2 3.8 2.0 1.0 2.6 _-_-_-_ ___ 7.1 1.9 -__ ___ __-
1.4
68.9
25.4
2.3
0.9
2.5
23:; ::: ___ _-_ ___ _-1.0
Oil 36.3 50.0 75.0 63.8
Nabgal 60.0 50.0 9.0
1
and the Arab countries. The uranium resources of the Arab countries are shown in Table 5. Uranium resources are concentrated in Algeria and Somalia. The known reserves of thorium deposits are mostly in Egypt and amount to 15,000280,ooO tons.’ It is important to remember that uranium and thorium may be used to produce Pu-239 and U-233 which are weapon-grade materials. For this reason data related to applications of these fuels are not freely available. Arab North African countries are particularly rich in phosphate deposits and almost all of these deposits contain from 0.1 to 0.2% of uranium. The uranium is extracted as a by-product. Arab phosphate production and reserves are given in Table 6. The introduction and growth of nuclear power in the Arab countries has been slow. As skilled manpower becomes available in countries such as Syria, Algeria, Egypt, and Iraq, it may become possible to exploit this new technology over the next few decades. The unified electrical networks of some of the Arab countries are capable of accommodating nuclear power plants of 200400 MWe, while Egypt can accommodate plants of 600-1200 MWe. A study by the International Atomic Energy Agency has shown that eight Arab countries are in a position to introduce nuclear energy by the year 1990.’ Algeria has followed an independent line towards developing uranium processing and fuel fabrication. The Algerian program favours indiginous growth of reactor technology to enable them to build their own reactor.’ Egypt has world
$j WT
0
90 6.
t
eZa
Insrolled
f359
Production
cop(IciTy power
z
70
C:: 0
60
300
lg
50
250
x 0 2
40
200
‘5 n e 0
30
150
5
20
100
=
10
50
La P g w
Years Fig. 4. Expected electrical energy production and installed capacity in the Arab countries.
The nuclear energy alternative in Arab countries
877
Table 5. Uranium reserves in Arab countries.
r
Country
I
Lkaniun researves, lo3 Tons 26.40 6.57 0.04 1.65 12.50
Algeria Egypt Morocco Sudan Somalia
I
Total
I
47.16
Table 6(a). Uranium as a by-product of phosphate in the Arab countries--phosphate production. Production of phosphate
Country
lo6
tons
Aver age uranium concentration
Extractable U30s in 1984, tons
DDm 0.946
0.708 0.363 4.390 17.094 1.460 4.730
100 90 75 120 120 100 50
27 526 2,050 146 236
3,142
29.700
~ 124.600
I
I
12,460
100
25.2
23
~
Table 6(b). Uranium as a by-product of phosphate in the Arab countriesphosphate reserves. Reserves
Total
Low
High
Ave.
Reasonably assured uranium in phosphate, reserves, tons
95 70 ___ 90
120 120 ___ 180
20,500 47,700 32,400 124,680 6.840.000 ___ -__ 62,400 39,750
of phosphate
lo6 tons
Country
Uranium concentration DPln -
Algeria Egypt Iraq Jordan Morocco Mauritania Saudi labia Syria Tunisia
205 530 432 1039 57000 ___ ___ 624 795
--624 --502 --100 190 235 ---
205 1154 432 1541 57000 ;: 859 795
G -__ 30 40
250 130 ___ 200 90
100 90 75 120 120 100 ___ 100 50
Total
60785
1651
62276
___
___
___
7,167.430
World
1300000
---
___
___
___
-__
13.000.000
1 ---
___
___
___
___
‘IL
47
55.1
HASSANE. S. FATHand HAMEEDH. HASHEM
878
2-MWe research reactor of Soviet design. During the last few years, Egypt has gone through several cycles of announcing the intent to build nuclear power plants with help of the U.S.A., France, Germany or Canada. Electricite de France (EdF) announced that the utility would be negotiating the Egypt contract as a turnkey operation, which will lead to two 900 MWe plants. On the other hand, the outcome of talks between Egypt and Canada is an agreement on nuclear cooperation, exchange of information, technology transfer, and supply of nuclear equipments and materials.’ Iraq also a 2 MWe research reactor similar to that of Egypt. This plant was built in 1968 with assistance from the U.S.S.R. Recently, Iraq has signed cooperation agreements with France and Italy for the supply of a high-flux 70-MWe research reactor. This reactor was destroyed by Israel in 1981. Iraq has also been negotiating with France for the supply of a 900-MWe reactor and more recently, with the U.S.S.R. for a 440-MWe reactor. As the result of the present Iraq-Iran war and the Israeli attack, the Iraqi program may be delayed.’ Syrian and Libyan plans are still at the negotiating stage with the U.S.S.R. to supply one 440-MWe reactor to each country.
NUCLEAR
TECHNOLOGY
TRANSFER
A primary contribution of nuclear power to the development of the Arab countries is and training activities. The technology transfer, with associated technical, educational introduction of an integrated technology-transfer plan implies involvement in all aspects of that technology, e.g., nuclear physics, electronics, as well as agricultural, biological, chemical, metallurgical, and other branches of science and technology. Each of these fields requires skilled and professional personnel and covers a broad range of activities, which includes the education of managers of complex organizations, specialist engineers and scientists in high-technology disciplines, graduate engineers and designers, and technicians in many fields who would all be of great help to the development of the Arab countries. The Arab countries already have a fairly large pool of trained manpower to seed the growth of such technology. Without a domestic manufacturing capability of nuclear-plant systems and components, the construction and maintenance of these plants would remain dependent on technology assistance from external suppliers and would therefore deplete foreign-currency reserves. The technology-transfer package should cover the following items: (i) research and development programs for which code development, experimental verifications and component tests are planned; (ii) engineering establishments where reactor systems and components are designed; (iii) fuel-cycle programs including uranium exploration, mining and fuel fabrication; (iv) manufacturing-technology transfer to allow in-house manufacture of reactor components; (v) educational programs in the universities, laboratories, and at reactor sites.
CANDU
AS A SUITABLE
TECHNOLOGY
The CANDU reactor is a pressurized heavy-water reactor (PHWR) fuelled with natural uranium oxide, clad in zirconium alloy. The fuel is loaded into horizontal pressure tubes, which pass through a large tank (the calandria) filled with a heavy-water moderator. Heavy water is used at high pressure as coolant. The CANDU system is fuelled on-load by two remotely operated machines. The fuelling machines simultaneously insert fresh fuel while removing a spent fuel bundle. The general economical, safety, and reliability advantages of the CANDU reactor will be discussed, together with an assessment of its suitability for energy and development programs in the Arab countries. Figure 5 summarizes the socio-economic impact of CANDU technology in the Arab countries.” Natural uranium and fuelsycle
jlexibility
The main advantages of the use of natural uranium in CANDU reactors are the following: (a) it widens the sources of supply and allows easier manufacture. This inexpensive fuel can be fabricated in the Arab countries without the need for enrichment technology. The Canadian
879
The nuclear energy alternative in Arab countries
CANDU reactor
Cheap and plentiful Developments
Decentralization
of the mining industry
;
and of uranium and thorium processing development industry
of capital goods
;
major capital construction
program
development
light
industries advancement
education
1 Indirect
Participation surplus
;
for personal development
for the rural population.
technological
benefits
[
in advanced systems research and development
electrolysis
, industry
.
steam for process
development advanced
and recreation
handicraft
;
such as electronic6 of technical
greater opportunities
;
;
of agriculture
and of small rural/urban
for nuclear components of specialized
of industry
greater productivity
;
electric poser
for hydrogen
fuel/feedstook
of a radiochemical
industry
treatment
facilities
minimizes
refrigeration
production
;
;
applications
Fig. 5. Impact tree of CANDU
;
,
medical
food irradiation
other industrial/educational
(R&D)
;
industries
needs
;
of radioisotopes.
technology transfer to the Arab countries.
companies are willing to share their expertise with countries undertaking a CANDU program.‘l (b) Consumption of natural uranium in the CANDU reactor is about 15% less than that of enriched-fuel reactors over the life of the reactor (see Table 7). (c) The CANDU fuel-cycle system can be developed to accommodate a new fuel cycle as the economic situation dictates. Good neutron economy of the reactor permits exploitation of a self-sufficient thorium fuel-cycle, which requires minor modifications to the reactor and permits the recycling of natural uranium fuel indefinitely with only a small addition of thorium. It should be noted that Egypt is relatively rich in thorium deposits.3 Security of fuel supply is an important factor for economic well being and development, as well as for political independence.
Table 7(a).
Approximate equilibrium fuel consumption.6
Reactor
CANDU
LWR
Fuel consumption kg/W-year
type
(natural uranium through)
(fuelled with uranium)
once
167
enriched
200
Table 7(b). Natural uranium required for 6000 MWe.6 Reactor
First
type
I
charge
I
Year Ly consumption
I
HASSANE.
880
S. FATHand HAMEED H.
HASHEM
The advantage of using pressure tubes
The use of pressure tubes in the reactor core allows the primary coolant system to be pressurized without the need for a massive pressure vessel. The advantage of this approach include the ability of local industry to participate significantly in construction, design, installation, component fabrication, and supply. This aspect has proved to be a primary advantage for developing countries such as Argentina, Korea, Romania, India, and Pakistan. Heavy-water technology
The availability of heavy water is important to operation of the CANDU reactor. Any country that participates in a CANDU program may buy, lease, or manufacture heavy water. Heavy water is uniformly distributed in ordinary light water (one part per 7000) and its production has been developed in Canada, the U.S.S.R., the U.S.A., and other countries. An essential feature of many CANDU proposals is the transfer of heavy-water technology in case the client requires self-sufficiency. The technology-transfer package includes plant siting and environmental-impact studies, plant design, vendor and contract selection, project schedule and cost control, quality-assurance program development, plant-personnel training programs, commissioning and start-up support, and operation support. The heavy water in the CANDU reactor eliminates the need for enriched uranium fuel, which is several orders of magnitude more difficult and expensive to produce than heavy water. In addition, uranium-enrichment technology is not being transferred. Moreover, heavy water is not a consumable item like enriched uranium, except that some of the deuterium is converted to tritium. On-power fueling The CANDU reactor-design arrangement allows use of on-power fuelling. This arrangement has the following advantages: (a) a high capacity factor is achieved because of high availability; Fig. 6 shows the annual load factor for 35 reactors; (b) defective fuel can be removed while reactor operation continues, which minimizes maintenance problems caused by high radiation fields in the reactor-coolant circuit; (c) on-load fuelling leads to optimal reactor-flux patterns and best fuel use; (d) because the CANDU system uses neutrons more efficiently than
Annual 70
75
I
I
load 80 I
factor 85 I
‘/. so I
E
AECL-CANDU KWU - PWR GETSCOBWR AECL - CANDU WestinghousePWR KWU - PWR GE-BWRVariousMAGNDX ACECOWEN -PWRGE- PWR Westmghouae -PWR
_ I_
AECL-CANDUMHI-PWRFramotoma - PWR ASEA-Atom --BWR _ Framatome-PWRGEC-MAGNOXAECL-CANDU Westinghouse -PWRACECOWEN
-
PWR
r-
Siemens -PWR l-1 GC-MAGNOXB ASEA-Atom-8WR_ Westrnahouse - PWR AkL-CANDU MHI-PWRWestinghouse-PWRF Siemens - PWRGE-BWRAECLCANDUEE/BW/TW-MAGNOXWestinghouse - PWR w
Fig. 6. Annual load factors for the top 35 reactors.
95 1
881
The nuclear energy alternative in Arab countries
3000
l
CANDU
multiple
0
Multiple
unit
D Slngk
0
lo
““““““““““’
1970
unit plant
un,t
plant
uA
0
plant
(LWR) L7
(LWt?)
1975 Midpoint
1980 of
in-service
1985
1990
dates
Fig. 7. Capital cost comparisons for CANDU and CWR reactors.
light-water reactors, it requires less uranium for a given electrical output. Accordingly, the fuel for CANDU reactors costs less than 60% of that for a PWR for the same amount of generated heat (see Table 7).‘l
Additional safety advantages of the CANDU
reactor
CANDU has no criticality problem with natural uranium spent fuel stored under water. Repair of fuel channels during the lifetime of a station is relatively easy. However, repair of a faulty pressure vessel is very difficult. The CANDU fuel channels, reactor controls and monitoring devices can be replaced in situ. The pressure tubes have the advantage that any cracks are revealed by leakage, which is easily detected. Breaks in one or several pressure tubes will have less serious consequences than a break in a large pressure vessel. Furthermore, the small diameter of the pressure tubes lowers the maximum potential discharge to containment in the event of a loss-of-coolant accident (LOCA) caused by a pressure-tube break. A serious pressure-tube crack associated with a LOCA was completely controlled and tube replacement was carried out in the Pickering reactor in Canada. The use of pressure tubes allows separation of coolant and moderator, which means that the reactivity-control devices are placed in a low-pressure and low-temperature environment that minimizes the likelihood of failure. Moreover, core melt-down is less likely to occur than in other reactor types because of the presence of three separate and independent heat sinks, namely, emergency core cooling (ECC), moderator, and shield-tank water. CA ND U economy Extensive information from electrical utilities in the U.S.A. and Canada indicates that the dry capital cost (the cost of the facility excluding fuel and heavy water) of a CANDU nuclear generating station is comparable to the dry capital cost of LWR stations (Fig. 7). The cost of the initial charge of heavy water and its replenishment, as required during the life of the plant, is offset by CANDU’s low fuelling cost. Accordingly, CANDU reactors provide the lowest cost for nuclear-generated electricity because of their high capacity factors.
REFERENCES 1. H. El-Khateeb,
“Electricity
in the Arab World,” Third Arab Energy Conference,
Algeria (1985).
2. OAPEC Bulletin, Kuwait (1986). 3. OAPEC, “The Secretary General’s Twelfth Annual Report,” AH 1405/AD, Kuwait (1985). 4. Arab Organisation for Mineral Resources (AOMR) , “Solid Energy Resources in the Arab Countries,”
Third Arab Energy Conference, Algeria (1985). “Biomass Energy in the Arab World,” Third Arab Energy
5. A. A. Shalash, (1985).
Conference,
Algeria
HA~.$ANE.
882 6. I. Ibrahim,
7. 8. 9.
10. 11.
S. FATH and HAMEED H. HASHEM
“Energy Demand and Consumption Forecasts in the Arab Countries,” Third Arab Energy Conference, Algeria (1985). Federal Institute for Geosciences and Natural Resources, “Survey of Energy Resources,” 11th World Energy Conference, Munich (September 1980). K. E. Effat, “Role of Nuclear Energy in the Developing Countries,” Third Arab Energy Conference, Algeria (1985). Nucl. Engng Znt. (January and March 1982). D. S. Lawson,” CANDU to Meet World’s Needs,” AECL-7502 (1981). J. Bouton, “What are the Prospects for CANDU in Mexico,” AECL-Marketing, lecture presented in Mississauga city, Ontario, Canada (May 1982).