Solar Cells, 6 (1982) 239 - 249 239

PHOTOVOLTAICS IN THE ARAB WORLD

M. A. KETTANI*

Islamic Foundation for Science, Technology and Development, P.O. Box 9833, Jeddah (Saudi Arabia)

(Received September 30, 1981)

Summary

There is great interest in photovoltaic conversion in the countries which make up the Arab world. Research in universities and applications in the field are both increasing at a fast pace. This paper gives an overview of all this activity and explains the reasons for this interest. More specifically it defines "economic attractiveness factors" such as "insolation fac tor" and "remoteness fac tor" tha t determine whether a photovoltaic application would be economical at a given geographical point.

1. In t roduct ion

The area under consideration comprises the countries of the Arab League (the Arab world). It includes territories extending over 77 ° longitude from the Atlantic Ocean (17 ° W longitude) to the Indian Ocean (60 ° E longitude} and over 35.5 ° lati tude from the Mediterranean coast (37.5 ° N lati tude) to tropical Africa (2 ° N latitude). It covers a total surface area of 13 700 000 km 2 of which 10 200 000 km z are in Africa and 3 500 000 km 2 in Asia. The total populat ion in 1981 was equal to 170 million people of whom 117 million were in Africa and 53 million in Asia.

The average insolation received by the Arab world can be estimted at about 520 cal cm -2 day - i (about 250 W m -2) or a total of 3.4 X 109

The average insolation received by the Arab world can be estimated at about 520 cal cm -2 day -1 (about 250 W m -2) or a total of 3.4 X 109 MW. In 1 year, therefore, the Arab world receives about 30 X 10 i5 kWh of solar energy or 100 Q units (1 Q = l 0 is B.t.u. = 2.93 X 10 i4 kWh), more than six times the estimated oil reserves of the Earth [1] . There are indications, however, that the diffuse componen t of insolation can be as high as 20%; this is due mostly to dust in the air which is widely present in desert areas.

*On leave from the University of Petroleum and Minerals, Dhahran, Saudi Arabia.

0379-6787/82/0000-0000/$02.75 © Elsevier Sequoia/Printed in The Netherlands

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2. Photovoltaic research in Arab countries [2]

Interest in solar energy in the Arab world started in the universities in the late 1950s and early 1960s. This interest took many forms, including basic research in photovoltaic power conversion. At present this research is carried out in only a few countries.

In Algeria, a photovoltaics group at the Centre des Sciences et de la Technologie Nucl~aire in Algiers studies and develops CdS-Cu2S thin film photocells and experiments with photovoltaic panels.

In Egypt, a group at the Solid State Laboratory, National Research Centre, Dokki, Cairo, works on semiconductors. The group has received scholarships from the Laboratoire de Bellevue, Solid State Physics, Centre National de la Recherche Scientifique (CNRS), and work is done mainly on CdS and CdTe. There is also interest in photovoltaic power conversion at the Physics Department, American University, Cairo, where research is carried out on silicon cells. Similar work is being done at the Mechanical Engineering Department, Al-Mansurah University.

Commercially available solar cells are tested in the Kuwait environment at the Physics Department of Kuwait University and, in Lebanon, the CNRS has supported a small photovoltaic conversion project involving experimen- tation with silicon cells.

The solar energy group at the Physics Department, Mohammed V University, Rabat, Morocco, established a photovoltaics laboratory in 1979.

In Saudi Arabia, studies mainly of a theoretical nature have been carried out at the Electrical Engineering Department, University of Petroleum and Minerals, on the direct conversion of solar energy into electricity, including photovoltaic conversion. Photovoltaic units for student demonstration are also located at the Mechanical Engineering Department, University of Riyadh.

In Sudan, the Solar Energy Department, Energy Research Institute, Khartoum, tests silicon photocells brought from the U.S.A. and incorporates them into integrators for solarimeters. Work on silicon photovoltaic cells is also carried out at the Physics Department, College of Science, University of Khartoum, mostly in cooperat ion with the Philips Company in the Netherlands.

The photovoltaics group at the Ecole Nationale d'Ing~nieurs de Tunis carries out the following projects in Tunisia.

(a) Cu -Cu20 photocells are produced by the oxidation of copper in vacuum at high temperatures; Cu20 has been obtained with an efficiency of 5%.

(b) Si-SnO2 Schot tky diodes (thin film heterojunctions) are fabricated by the deposition of SnO 2 on silicon monocrystals using the spray method. The deposition of indium oxide (In203) on silicon is also tested. Efficiencies of 7% have been obtained.

(c) Hydrogen is produced by photoelectrolysis using Ti-TiO 2 diodes. (d) Silicon monocrystals and possibly amorphous silicon are produced.

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(e) Photovoltaic plants are modelled theoretically using computers to study absorption, spectral response and barriers.

(f) AsGa photocells are fabricated by evaporation. (g) Work on CdS and CdTe and on the electroreflectance for interface

studies is being carried out in cooperation with Nice University, France. The Laboratoire de Bellevue, CNRS, helps this group by supplying it with raw materials.

The photovoltalcs group at the Faculty of Sciences, Tunis University, has two projects.

(a) GaxAll-x As is studied by the Raman resonant effect in collabora- tion with the Centre of Electronic Studies, Montpellier, France.

(b) The optical properties and transfer phenomena are investigated in non-homogeneous semiconductor components, such as semiconductors with dendritic surfaces and semiconductors with impurities (e.g. germanium in A1203) , in collaboration with Exxon Linden, New York, and the University of Sydney, New South Wales, Australia.

Another photovoltaics group, that at the Faculty of Sciences and Technology, Sfax, is interested in Schottky heterojunctions, such as Si-A1, Si-Au, Si-SiO2-A1 and Si-SiOe-Au, produced under vacuum.

3. Photovoltaic projects in Arab countries [2]

Demonstration projects are in operation in many Arab countries. In Egypt, bids have been made by the Ministry of Electricity and

Energy for photovoltaic cells and photovoltaic irrigation pumps. A profes- sor from the American University, Cairo, has studied the social impact of television using photovoltaic cells on a remote village in the Nile delta.

The Jordanian Telecommunication Corporation, Amman, has developed a photovoltaic-powered telephone system for remote villages. Another project, sponsored in part by the Jordanian army, consists of the installation of more than 100 emergency photovoltaic-powered telephones along highways. One of the features of this project is the achievement of the construction of a low consumption transmitter-receiver suitable for the photocell power capacity. Passive cooling was provided in the pole structure in order to avoid overheating of the electronic parts.

The government in Oman has considered the installation of photo- voltaic plants of 15 kW capacity for desalting sea water in remote villages and, in Qatar, a small demonstration photovoltaic generator was installed by Lucas Service Overseas, Gt. Britain, in 1977.

In Saudi Arabia, the Saudi Arabian Centre of Science and Technology and the U.S. Department of Energy manage jointly the Saudi Arabian-U.S. Program for Cooperation in Solar Energy (SOLERAS) initiated in 1978. This is a 5 year programme, financed equally by the two governments to a total of U.S. $100 million. One of the most important projects being implemented under this programme is the establishment of a 350 kW

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photovoltaic station near Riyadh. A large U.S. aerospace firm won the U.S. $30 million design and construction project. The system is made up of 160 photovoltaic concentrator arrays, each array containing 272 silicon cells. Point-focusing Fresnel lenses concentrate the Sun's rays by a factor of 33. The system will be in commission by the end of 1981. In addition, a photo- voltaics firm has built a photovoltaic-powered house for demonstration, to the north of Jeddah; desalination of water, air conditioning and lighting are all powered by the Sun.

A general agreement for collaboration on solar energy was signed in 1977 between Electricit~ de France (EDF) and Electrico (a branch of the Ministry of Industry and Electricity, Riyadh, Saudi Arabia). This was followed in 1978 by a specific agreement worth U.S. $5 million whereby EDF supplied the ministry with one 30 kW Solar Energy Research Inst i tu te-Renaul t photopile unit at a cost of FF 6 million (and one 45 kW pump made by the Soci~t~ Fran~aise d 'Etudes Thermiques et d'Energie Solaire).

Small photovoltaic applications in Saudi Arabia started in the early 1960s with the installation of the first (French) photovoltaic beacon at Madinah airport. By 1980, the General Directorate of Telephones had installed more than 300 photovoltaic emergency telephones on the Saudi highways.

In Sudan, it is proposed to use solar electricity in a solar village project in the north of the Kordofan province.

In 1980, the Ministry of Electricity in Syria bought a 0.8 kW photo- voltaic generator from France for experimental purposes.

In Tunisia, the Research Institute on Arid Zones, Ariana, has received a photovoltaic pump from Elf-Aquitaine, France, at a cost of U.S. $6000. If this proves to be a success, more than 20 such pumps will be ordered. In contrast, in 1972 the Ministry of Agriculture installed a photovoltaic pump ordered from Mabosun, Italy, at Tozeur. It pumped 5 - 20 m s h -1 of water from a height of 20 m. The Ministry later ordered ten more pumps of the same type.

One 5 kW photocell pump has been installed at Garak in Mauritania for irrigation purposes. It was ordered from France at a cost of U.S. $130 000. Solar electricity is being considered for rural settlements also.

4. Why solar energy in the Arab world?

In Table 1 the potential amount of renewable energy available every year in the Arab world and the percentages used in the year 1980 are arranged in categories. The energy consumption of the Arab world, both fossil and renewable, is presented in Table 2 [3].

It must be pointed out here that in 1977 the quanti ty of flared gas in the Arab world amounted to 840 × 1 0 6 MW h year -1, a quanti ty almost equal to the total energy consumption of the entire Arab world during that year. The total reserves of fossil fuel in the Arab world do not exceed

T A B L E 1

R e n e w a b l e energy sources in t he Arab wor ld in 1980

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Energy source Po ten t ia l energy C o n s u m e d energy C o n s u m e d energy (X 106 MW h y e a r - l ) a (x 106 MW h y e a r - l ) a (%)

Solar 2 7 0 0 0 0 0 0 - - 0 Wind 1 6 0 0 0 0 0 0 - - 0 G e o t h e r m a l 22000 - - 0 Biomass 1700 38 2 Hydraul ic 43 19 43

To ta l 4 3 0 0 0 0 0 0 57 1 p p m

a106 MW h is equ iva len t to 0 .086 mi l l ion t o n n e s o f oil, i.e. 0 .112 mi l l ion barrels of oil.

T A B L E 2

Energy c o n s u m e d in t he Arab wor ld in 1977 a

Energy source Energy c o n s u m e d C o n s u m e d energy (x 106 MW h year - 1 ) (%)

Oil 457 49.7 Na tu ra l gas 349 38.0 Coal 6 0.7

To ta l fossil 812 88.4

Biomass 92 10.0 Hydrau l ic 15 1.6

To ta l r enewab le 107 11.6

To ta l c o n s u m p t i o n 919 100.0

a Calcu la t ions based on U n i t e d Na t ions ' data .

4 000 000 X 106 MW h of which 12 000 X 1 0 6 a r e extracted annually, most ly for export . If the probable reserves were taken into account, the above figure could be doubled. As for nuclear energy, the reserves of the Arab world amount to 100 000 tonnes of uranium. There are also large quantities of coal and shale oil in the Arab world.

In terms of quanti ty , the Arab world as a whole seems to be well endowed with energy resources. However, there are two facts tha t could influence its future as far as energy is concerned: (1) fossil fuels are, for the Arab world, as much a source of cash for development as they are a source of energy; (2) the technology of renewable energy sources is ye t to be developed. In Table 3 an assessment of the energy consumption of the Arab world in the year 2000 is given on the basis of the most optimistic proposi- t ion for renewable sources. In this table two facts are clearly demonstrated:

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TABLE 3

Projected energy consumption of the Arab world for the year 2000 A.D.

Energy source Energy consumption Total consumed Potential (x 106 MW h year -1) energy (%) energy (%)

Oil 1800 45 --- Natural gas 1400 35 -- Coal 50 1.3 -- Nuclear energy 500 12.5 --

Subtotal 3750 93.8 --

Biomass 170 4.3 10 Hydraulic 43 1.0 100 Solar 17 0.4 -- Wind 5 0.1 -- Geothermal 15 0.4 --

Subtotal 250 6.2 --

Grand total 4000 100.0

(1) the deve lopmen t o f renewable energy sources, including solar energy, in the Arab world is necessary to respond to the increasing demand ; (2) even if the deve lopmen t of these sources is s tar ted now, the Arab world c a n n o t af ford to ignore coal and nuclear energy for long.

5. Economic attractiveness factors

Solar energy in its e lec t romagnet ic fo rm is a raw material which is useless unless it is processed proper ly , i.e. unless it is conver ted into a useful form such as electrical energy. To assess the economic feasibility o f such a solar convers ion system, it is necessary to find a break-even cos t model . One such mode l leads to the break-even cos t by calculat ion o f the present value o f the average annual saving of a solar energy sys tem c o m p a r e d with a convent iona l energy system. The solar sys tem is assumed to be f inanced by a mor tgage with a p rede te rmined interest rate for a specific per iod o f time. The average annual saving made, if any, due to the ut i l izat ion o f the solar energy sys tem will be equal to the annual opera t ing cos t o f the solar energy sys tem minus the sum of the annual opera t ing cos t o f the convent iona l energy sys tem and the cos t o f mainta in ing the solar system. Fu r the rmore , the opera t ing cos t o f the conven t iona l sys tem is assumed to increase year ly at a cons t an t rate. The mode l could o f course be improved to take in to a ccoun t the f luc tua t ion in the value o f m o n e y with t ime and the d i scount value o f the year ly energy savings. Other models , slightly d i f ferent f rom the above, have also been p roposed [4, 5 ] .

The cos t of a pho tovo l ta ic sys tem can be divided in to two parts: the cost o f the land and the cos t o f the s t ructure . In desert and r emote areas,

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land cost may be a negligible part of the overall cost while, in densely populated areas, it cannot be neglected. The cost of the structure is basically related to the cost of production of high purity silicon. The cost of silicon more than doubles (U.S. $650 kg -1) when it is processed from an ingot into wafers, since about 50% of the starting material is lost. Development of the edge-defined film growth, producing silicon in the form of a ribbon, should cut down these costs. Lower costs could be expected with concentration since it would reduce the amount of silicon required.

The factor that could finally decide the economic viability of a photo- voltaic system is the break-even cost. A break-even cost factor K can be defined as the ratio of the break-even cost at a given location to the break- even cost at a reference point. K is a function of the cost of fossil fuel, land and labour; these can all be expressed in terms of a factor of remoteness, at. A point A is said to be remote if communicat ion between point A and the centre of manufacture, if any, or the centre of import, point B, is difficult. The more difficult communications are, the more remote the point is con- sidered to be. Such remoteness means that the cost of transport of fuel and materials is high and therefore the break-even cost of photovoltaic electricity is high. The break-even cost is also a function of the amount of insolation; it is, of course, lower for lower insolation and vice versa. All other factors can be reduced to the remoteness factor and the factor of insolation. Thus, it can be concluded that, if o~ i is the factor of insolation {expressed as a ratio to a reference point), then

K = f(~r, (~i)

A solar system becomes economically feasible at any given geographical point when the break-even cost is reached, i.e. when the cost Cs of a unit of energy produced from solar energy becomes the same as the cost Co of the same unit of energy produced from fossil fuel (Cs = Co ). However, Cs is directly proportional to the amount of insolation, whereas Co is a function of the remoteness of the given geographical point:

C s = Cs0OL i

C c = Ce0OLr

From the above, the break-even factor is

K = OLiOL r

The higher the value of K is, the more economical is the photovoltaic device. The insolation factor ~i varies from 1.1 in north-west Syria and north-

east Tunisia (for a reference point with an insolation of 300 cal cm- 2 day- 1 ) to about 3.2 in the empty quarter of Saudi Arabia [6, 7]. In contrast, the remoteness factor ~, depends on the existence of roads, the nature of the terrain, distance etc. It varies from 1 in such cities as Jeddah or Casablanca to more than 15 in the empty quarter of Saudi Arabia. Thus, K can vary from 1 to above 20 as shown in Fig. 1 [8]. A solar system might be

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Fig. 1. Solar energy activity and lines of equal break-even factor in the Arab world (countries underlined are those from which information was gathered): (~), existing solar energy laboratory; Q , planned solar energy laboratory; (~), planned solar village; (~), universities doing or interested in solar energy work; (~), Qattarah-type project; (~), company producing solar water heaters; (~), solar greenhouses; [~], solar pumping station (existing, obsolete or planned); [ ] , major desalination plant (existing or obsolete); ~-], planned major solar heating project; [-~, national solar energy society or chapter of Inter- national Solar Energy Society; 1~1, locale of international conference on solar energy.

economical at a point where K = 20, even though its cost would be much higher than the break-even cost at a point where K = 1.

However, this entire economic picture could easily be overshadowed by government legislation. If governments encouraged the extensive use of solar energy rather than other sources of energy, photovoltaics could be made much more competitive. Encouragement can take the form of tax breaks, bonuses, participation in investment, subventions etc. At present this form of encouragement is not being given in the Arab world. On the contrary, the subsidies given by most Arab oil-exporting countries to the generation of electricity using fossil fuels are such that the consumer ends up paying no more than 10% of the cost of the electricity that is received; the remainder is paid by the government. This situation makes photovoltaics much less competitive.

6. Social and ecological impacts The utilization of solar energy in a society will have an impact both on

the environment and on the behaviour and habits of individuals, the two being interrelated.

The fact that solar energy is not concentrated makes it most applicable to a decentralized mode of energy consumption and well suited to most Arab lands outside large cities. The large-scale utilization of solar energy will reduce the consumption of fossil fuels and, consequently, the amount of pollution that results from burning them, and the quality of the environment will therefore be improved.

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In rural regions where fossil fuels are hardly used and where firewood is used instead, the use of solar energy will reduce the reliance on firewood and consequently help to prevent land from becoming desert, a continuous problem in many Arab regions. Where there are no conventional sources of energy, solar energy is always available in the Arab world to help to improve the quality of life of the people.

The negative effect of solar energy on the environment stems primarily from two sources: land usage and potential pollution due to the manufacture of products necessary for the fabrication of photovoltaic cells and systems.

The use of solar energy in buildings will greatly influence the choice of orientation of these buildings with respect to insolation. In turn, this will influence the positioning of water lines, sewers, electric mains, road direc- tions etc. In already established settlements, the new orientation require- ments are certain to lead to tremendous problems.

The use of solar energy on a large scale necessitates large collecting areas and therefore extensive land use comparable with that necessitated by conventional energy sources. However, land used for solar energy is affected much less than that used for fossil fuels.

The impact of solar industry on the environment would not differ very much from that resulting from any other industrial activity. In a comparison of the effects on health resulting from the production of electricity from fossil fuels or nuclear sources with those resulting from production using solar power, solar electricity stands out as the best option because of its safety and the lack of poisonous emissions such as carbon dioxide.

The utilization of solar energy would have a limited impact on the overall heat balance of the environment. However, the collection of solar energy that would otherwise have been reflected back into the atmosphere (e.g. by satellites} would certainly influence the overall microclimate if it were carried out on a large scale.

If solar energy was taken into account in the building of homes and cities it would certainly influence architectural styles and, in the long term, the social habits of the population. However, it is wrong to assume that social habits would change quickly because of the will of the engineer or the architect. Therefore, solar energy will have to adapt to the social preferences of the population of the Arab world.

The most dramatic potential influence of solar energy in the Arab world is in rural areas. In these regions most of the burden of the lack of energy resources falls on women. It is the women who, for example, gather wood to build fires and who go to the well, often carrying water over large distances. Solar energy would free women in rural areas for more rewarding activities such as educating themselves, raising their children better and taking a fuller role in the social activities of their communities.

However, if solar energy is to be used meaningfully, solar equipment must be manufactured within the Arab world. The utilization of solar energy on a large scale would then help to create more jobs. Furthermore, it would make the sett lement of otherwise remote and arid areas possible and acceptable.

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7. Problems of implementation

From the above discussion, it appears that, although the potential for photovoltaic applications in the Arab world is enormous, the existing research activities are weak, sketchy and unimpressive. The majority are essentially in the universities and are linked financially to a programme in one or more of the developed countries. Most of the photovoltaic projects, including the largest ones, either use imports of foreign products or are demonstrations of systems which have been developed, designed and installed by agencies outside the Arab world.

It is true that interest in solar energy was initiated in the industrial world which still sets the tone for research and development. In fact many industrial countries, devoid of much solar energy, develop it almost exclu- sively for potentially attractive markets in the solar-rich developing world, including the Arab world. These countries with their wider scientific base, technical expertise and much larger markets are in a better position to bring the products of research to the industrial production line. Their interest in Arab countries arises from the fact that they provide ideal ground for experi- mentat ion and demonstrat ion and are attractive future markets that cannot be ignored.

Most Arab countries are acutely aware of their limitations in their efforts to develop solar energy. However, most have solved this problem by turning to the industrialized world for finance and/or training. Often, their solar energy plan becomes completely integrated in the overall development plan of the industrial power rather than with neighbouring countries which might have similar conditions vis-d-vis solar energy.

Arab countries are characterized by a limitation in one or more of these factors: (1) financial resources; (2) trained manpower; (3) buying power. Common sense dictates regional cooperation between them and the creation of common markets at least for solar energy products and talents. An effort towards this direction was started when the Organization of Arab Petroleum Exporting Countries initiated the 1st Arab Energy Conference (Abu Dhabi, 1979) (conferences will now take place every 3 years). This Conference, which gathered the top decision makers and researchers in the field of energy in the 21 Arab states, recommended that every Arab country should create a state energy commission which would coordinate all matters of energy within a given Arab state. This recommendation was implemented by 18 of the 21 states. It is a first step towards the formation of an Arab Energy Commission which would coordinate energy programmes in the Arab world. Renewable energy sources and especially solar energy would have an important place in these programmes.

Complementary and parallel efforts are being made by the Organization of the Islamic Conference (OIC) to which the 21 Arab states belong in addition to 22 other states from Asia and Africa. Indeed, the OIC created the Islamic Foundation for Science, Technology and Development with the aim of promoting common programmes, including the development of solar energy.

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8. Conclusions

The cost of solar energy arises from the cost of the materials which have been developed for processing it. This is expressed by the cost of the photovoltaic converter. If Arab countries import these converters from industrialized countries, they will be importing solar energy. Thus, if Arab countries are seriously to encourage solar energy applications to help to balance their energy needs, now and in the future, they will have to encourage local research, development and manufacture of solar systems. A reliance on indigenous talent must be stressed in each country and strong links must be formed between the research centres, such as universities, within each country and the manufacturing sectors of its economy. Arab governments should intervene to create a solar energy programme of research and development which is an integral part of the overall develop- ment programme of the country. Legislation should be brought in to open the entire Arab market for Arab products, to give encouragement to researchers, industrialists and consumers and to provide reasonable protec- tion from competi t ion outside the Arab world.

Arab governments are also advised to adopt widespread programmes of education. These programmes should start with the training of technicians in solar technology or the re-education of technicians from other fields and with the education of engineers and scientists. They should also provide more widespread education for the policy and decision makers and for the public about what they may expect from solar energy. Energy problems, including those of solar energy, should be incorporated into curricula in high schools and universities. Training for technicians, symposia and short courses should be organized periodically as technology is developed in the country.

References

1 M. A. Kettani, The energy problem: present situation and future alternatives for the gulf region, 1st Gulf Conf., Bahrain, March 19 78.

2 M. A. Kettani and M. A. S. Malik, Solar Energy in the Arab World: Policies and Programs, Organization of Arab Petroleum Exporting Countries, Kuwait, 1979.

3 M. A. Kettani, The role of renewable energy sources in the Arab world, Syrup. on Solar Energy and its Applications, March 7 - 11, 1981, Kuwait (in Arabic).

4 M. Saif-ul-Rahman, Economic competitiveness of solar energy with conventional fuel and electricity, Sol. Energy, 18 (1976) 577.

5 R. L. Reid et al., Economics of solar heating with home-owner-type financing, Sol. Energy, 19 (1977) 513.

6 M. A. Kettani and E. Y. Lain, Attempts at mapping the solar intensity distribution for the Arabian peninsula, Comples, (1974) 3 - 7.

7 T. H. Von der Haar, Solar insolation microclimate determined using satellite data. In C. Turner (ed.), Proc. Solar Energy Data Workshop, September 1974, in N S F - R A N N Publ. 74 - 062, 1974 (National Science Foundation).

8 M. A. Kettani, Prospects for photovoltaics in the Arab world, Proc. 3rd Commission o f European Communities Conf. on Photovoltaic Solar Energy, Reidel, Dordrecht, 1981.