Jesmin Sultana

K A Khan

Mesbahuddin Ahmed

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ASA University Review, Vol. 6 No. 1, January–June, 2012 
Solar Thermal Technology for Use in Developing Countries 
 
Jesmin Sultana* 
K.A. Khan** 
Mesbahuddin Ahmed*** 
Abstract 
Solar thermal is an alternative energy conversion process like photovoltaic system. There is 
a wide application of solar thermal energy in our domestic life and industrial arena. In this 
paper some notable examples of solar thermal applications have been discussed. This paper 
also refereed the application of solar thermal in different developing countries. 
Introduction 
Although the ideas of conservation are probably as old as human species, the use of the word 
in its present context is relatively recent. Conversation of energy involves practices that 
perpetuate the resources of the earth on which human beings depend. Energy extraction, 
collection, distribution and utilization: all these stages of energy technology are equally 
important for maximizing our energy resource capacity. Nevertheless, efficient collection of 
solar energy calls for special attention since there is a room for drastic improvisation in this 
field. This is even more important in the perspective of the developing countries, where there 
are an urgent and immediate need for generating a huge amount of electricity and thermal 
energy. Many attempts have been made to use solar energy to operate power plants to heat 
water, cook food, distill water, industrial process heating and cooking and so on. Other 
potential applications that may be mentioned are drying of agricultural products, steam 
generation, timber seasoning, purification of drinking water etc. A practical use of solar 
energy depends on the collection of insulation and conversion into thermal energy since 
thermal energy is the intermediate stage of any other energy conversion stag. Once enough 
thermal energy is collected, other useful higher-grade energy (i.e., electricity) becomes 
attainable at good efficiency. 
Different Applications of Solar Thermal Energy 
Solar thermal energy has some promising applications in our day-to-day life especially in 
rural areas. Tremendous opportunities are there in the field of solar thermal arena. New 
schemes are evolving both in developing and developed countries. Production of electricity by 
solar thermal technology is a very lucrative agenda now in Western USA. In Europe, solar 
greenhouse projects are improving time to time. Most important fields of solar thermal 
applications are sketched below: 
 
Water heater: Heating of water using solar energy has the commercial application, which is 
economically viable. In tropical countries solar water heaters find wide application in large 
establishments like hospitals, hostels and industries. Different types of solar water heaters 
have known considerable developments in different countries like Greece [Karagiorgas et. al. 
(2000)]. Cyprus [Kalgiro (1997)] (it is repeated that there is one solar heater for every 5 
people in the island), India, South Africa [Mathews (2000)]. Switzerland etc. 
                                                 
   *Ph. D Researcher, Department of Physics, University of Dhaka 
 **Chairman, Department  of Physics, Jagannath Universtiy, Dhaka. 
***Vice Chancellor, Jagannath Universtiy, Dhaka. 
16  ASA University Review, Vol. 6 No. 1, January–June, 2012 
 
 
Two types of solar hot water system are fabricated in Bangladesh (Taskina 1996)] each of 400 
litres of capacity per day at the temperature range (55-60) degree celcius. 
Applications: Water heater for domestic use, Hotels, Hospitals, and Industrial process 
etc. 
 
Air heater: Solar air heating systems use air to transport from warm spaces (directly or 
indirectly) to heat ventilation air, or heat domestic hot water. Alamdari studied the 
performance of two pass flat plate solar air heater in which air flowing simultaneously over & 
under the absorbing plate by using of laminar flow assumption for flowing air [Alamdari 
(2000)]. For a given air mass, it is found that the useful heat gain by air and performance of 
two-pass solar air heater is greater than one-pass solar air heater. The multi-pass airflow in the 
solar air heater gives higher efficiency. 
Applications: Space heating. 
 
Solar cooker: The major portion of energy consumption in developing countries is for 
cooking in domestic sector. 62% of world population rely on firewood for cooking, which is 
becoming scarce. Solar cooking seems to be a feasible proposition. According to Nahar 
[Nahar (2000)], the improved non-tracking solar cooker has been found best among solar 
oven, hot box cooker etc. The efficiency of this cooker is 28,.9% and save about 1400MJ of 
energy per year. 
Applications: Steam production and distillation. Hot water production, cooking etc. 
 
Solar dryer: Natural solar drying of food remains the main drying method for most of the 
rural people in developing countries. But it has many disadvantages. Large amounts of 
agricultural products are lost in most of the developing countries. But it has many 
disadvantages. Large amounts of agricultural products are lost in most of the developing 
countries. New technologies should always be introduced to save food for the increasing 
world population. It is hoped that the solar drying will be an important method of food 
preservation for the coming 2l century. 
Applications: Wood Seasoning, Solar Tunnel Dryer, Tobaco Curing, Fish drying etc. 
 
Refrigeration and cooling system: Conventional energy scarcity in some regions, 
environmental concerns and the favorable solar radiation cycle support solar refrigeration. A 
new solar powered air conditioning system has been developed where water is used as the 
refrigerant instead of CFC, is an environmentally sound system [Wolpert (2000)]. 
 
Adsorption cycles can be used in heat driven refrigerators, air conditioners or heat pumps in 
which the energy source is a burning fuel or waste heat. Examples include the use of waste 
heat to provide cooling, heat pumping, industrial refrigeration, vehicle air-conditioning and 
the refrigeration of food in parts of the developing world where there is no electricity supply 
to power conventional vapor compression. Critoph’s [Critoph (2000)] work established a 
solar power adsorption refrigeration system. Solar Powered vapor compression, LiBr-H20, 
H2o-NH3, AC-Methanol and CaCI2-NH3 systems have potentials for early entry into the 
market. Their high cost and low overall Cycle or Solar Coefficient of Performance (COP) 
(0.10-0.45) requires significant improvements to complete favorably with grid powered vapor 
compression units with overall COP of about 1.0. 
Solar Thermal Technology for Use in Developing Countries 17 
 
Applications: Solar Air Cooling is used in Cold Storage and Cooled in House. Solar 
Refrigeration is used to preserve meat, fish, fruits, Vegetables, Food etc for a long time. 
 
Solar electricity generation: Solar thermal technology using concentrating systems is 
applicable for solar electricity and/or for process heat generation. Both applications may use 
similar concentrating collector systems (dish, tower and trough systems), but of different 
engineering approach and specifications. They are applicable for central and distributed 
electricity generation. For the generation of bulk electricity, after wind facilities, solar thermal 
power plants possess the highest potential for competing with conventional power plants. 
While the solar electricity generation by solar thermal technology was the favorite starting 
base for the R&D efforts, resulting in first commercial success of nine parabolic trough power 
plants with 354 MW energy of total installed plant capacity in the South-Western USA energy 
market of California, the large solar process heat potential is yet nearly unexplored [Becker et. 
al. (2000)]. 
Applications: Different types of Solar Concentrators are used to generate electricity. 
 
Solar green houses: The solar greenhouses are intended to provide the much-needed heat to 
facilitate the healthy growth of agricultural plants especially during the cold period. The 
greenhouses in Western Europe should be designed to collect as much solar energy as 
possible, In these constructions, solar radiation is used for heating as well as for photo-
biomass conversion via the photosynthesis process [Granqvist et. al. (1998)1. Under certain 
circumstances, however, optimal plant production requires the greenhouse to be cooled. Pollet 
et. al. (2000) designed an effective low cost system which should enable to lower the inside 
air temperature of an earth tube heat exchanger system for greenhouses. 
 
Solar Gur Production: Date Palm Juice are produced by Different types of Solar 
Concentrators like Fresnel Reflecting concentrator, Paraboloidal Concentrator, Cylindrical 
Paraboloidal Parabolic Trough, Compound Parabolic Collector(CPC) etc. In the southern 
region of Bangladesh this solar system will prevent the cutting of Forests. 
 
Solar Paddy boiling:  At 80 degree celcius temperature Paddy has been boiled and is 
possible with any type of Solar concentrator like Fresnel Reflecting concentrator, 
Paraboloidal Concentrator, Cylindrical Paraboloidal Parabolic Trough, Compound Parabolic 
Collector(CPC) etc   under the Climatic condition of Bangladesh. 
 
Solar Tobacco Curing: To keep the humidity, the process of tobacco curing has been divided 
in to three parts. The process such as: 
(a) Virginia Tobacco:  In this process Tobacco is cured by Hot Gas flow. 
(b) Barly and Meriland Tobacco:  In this process Tobacco is cured by Hot Air. 
(c) Terkis: In this process Tobacco is cured by Solar Radiation. 
 
Solar Candle Production: The working principle of Solar system for Candle Production is 
very simple. Any Person with little training can do this job. The Solar system needs no extra 
space and can be operated in the house, terrace, courtyard, field or any open space where 
Solar radiation are easily available. The solar system is quite simple and successful for 
convenient candle Production. This system is likely to generate the employment among the 
18  ASA University Review, Vol. 6 No. 1, January–June, 2012 
 
 
needy people of Bangladesh. Any Bangladeshi Business Company can take-up this 
technology for its commercialization all over Bangladesh. 
 
Solar Soap Production: Soap comprises the sodium or potassium salts of various fatty acids 
such as Oleic, Stearic, Palmtic, Larric and mysteric acids. For generation its use has increased 
until its manufacture has become an industry essential to the comfort and health of civilized 
human begins. Sodium salts are called hard soaps and Potassium salts are called soft soaps. 
The soaps are soluble in water and the solution has excellent lathering and clearing properties. 
The basic principle of making all kinds of soap such as toilet, laundry, household, medicinal, 
marine and industrial soap is the same. The combination of higher fatty acids with sodium or 
potassium hydroxide or carbonate. Shaving cream soap are well known examples of soft 
soaps, while other types given above are examples of hard soap. Soap is either made by hot 
process or cold process. Usually laundry soap or bath or toilet soaps are manufactured by hot 
process. Transport and other special types of soap are made by Cold process. In our solar 
system soap obtained from the hot process by any type of Solar Concentrators like Fresnel 
Reflecting concentrator, Paraboloidal Concentrator, Cylindrical Paraboloidal Parabolic 
Trough, Compound Parabolic Collector(CPC) etc. 
 
Solar steam Production & Distillation: Solar thermal steam production and distillation of 
water by making good use of the solar system may be made by very useful and purposeful in 
the context of energy consumption pattern of the rural areas of Bangladesh where the 
conventional energy sources are scarce and merge. These distillation device can serve many 
purposes in rural health centres and can be utilized as a deasalination device in coastal areas. 
The steam produced at the atmospheric pressure can be utilized in sterilizing the bandages 
materials and operation tools of the rural health centres where conventional steam plant is not 
available. 
 
Other uses: Solar poultry chicken broader [Sheyin (2000)], solar egg incubators and hatching 
machines are not yet finding widespread utilization in poultry production. These depend on 
solar thermal. There are a lot more applications on solar thermal but most of these scopes are 
beyond the reach of the poor people. 
Conclusion 
Solar energy is an important and environmentally compatible source of renewable energy. 
Presently, many research and development programmes in developing countries are oriented 
towards the effective utilization of solar energy technologies, Moreover, current interest and 
activities in the field of solar thermal for various applications are also expanding rapidly. And 
in every case, supports from different corners are prerequisite for the rapid improvement of 
solar thermal application in developing countries. 
 
References 
Karagiorgas, M. Botzios. A. 2000. Solar water heater technology in Greece. World Renewable Energy 
Congress VI (WREC 2000). H: 940-945. 
Kalgiro, S. 1997, Solar water heating in Cyprus: Current status of Technology & Problems. Renewable 
Energy, 10: 107-1 12. 
Solar Thermal Technology for Use in Developing Countries 19 
 
Mathews, E.H. Taylor, P.B. Kleingeld, M. and O’Riordan, L. 2000. A new concept low-cost solar 
water heater. World Renewable Energy Congress VI (WRE 2000). H: 1015-1018). 
Taskina Khan. 22-26 Dec, 1996. Performance study of solar water heater system suited for small scale 
industries and rural hospitals. Proceedings of the regional workshop on Rural electrification 
through solar photovoltaic, and rural energy planning with renewable energy. 
Alamdari. G.S. 2000. Performance study of two-pass flat plate solar air heater. World Renewable 
Energy Congress VI (WREC 2000). H: 986-989. 
Nahar, N.M. 2000. Solar cooking- An appropriate technology for developing countries. World 
Renewable Energy Congress VI (WREC 2000). IV: 2245-2248. 
Woolpert J.L. Nguyen, M.V. Riffat, S.B. 2000. Solar powered air conditioning system for a hospital in 
Manzanillo World Renewable Energy Congress VI (WREC 2000) IV 2228-2231). Critoph, 
R.E. 2000. Rapid cycling solar/biomass powered absorption refrigeration system. World 
Renewable Energy Congress VI (WREC 2000). H: 959-964. 
Becker, M. Buck, R. Geyer, M. 2000. Solar Thermal Technology for power plants and process heat. 
World Renewable Energy Congress VI (WREC 2000). H: 1065-1070. 
Granqvist, C.G. Wittwer, V. 1998. Materials for solar energy conversion: An overview. Solar Energy 
Mat. Solar Cells. 54: 39-48. 
Pollet. 1 .V. Pieters, J.G. July 2000. Design of an earth tube heat exchanger system for greenhouses. 
World Renewable Energy Congress VI (WREC 2000). H: 1149 — 1152. 
Sheyin, F.T. July 2000. Solar energy utilization in agriculture in Nigeria. World Renewable Energy 
Congress VI (WREC 2000). IV: 226 1-2265. 
 
 


Solar Thermal Technology for Use in Developing Countries

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