The potential utilization of solar energy in Malta with emphasis on domestic solar water heating

Abstract

This dissertation is concerned mainly with the potential of solar energy in Malta, and its utilization for domestic water heating. It has been laid out in four chapters as follows: The first chapter is entitled ‘Non Renewable and Renewable Energy Sources’. The non-renewable energy sources are described in detail in the first part – particular attention is given to the fossil fuels oil, coal and natural gas, their supply and consumption, their economic and environmental impacts and their supplies for the future. The information as presented, stresses the need and lays importance on the fact that developed regions of the world can and should conserve liquid fuels so that the developing world will have access to these fuels that are ideally suited for economic development. Another aspect is dealt with is that irrespective of what improvements in energy efficiency can be achieved it is clear that the present sources of energy will ultimately become too expensive to extract, become relatively scarce and therefore eventually would to be replaced by other alternative sources. This chapter includes also a section on energy in Malta with importance given to the electricity generation, particular to the domestic sector. Discussion on the alternative sources of energy is presented in the second section of this chapter. This section introduces the reader to one important renewable energy source – solar energy. Developing countries like Malta, should lay importance on such an abundant source, firstly to supplement their energy needs and secondly to save on their import fuel bills. Solar energy is being widely advocated as a future energy source and this section discusses mainly the utilization of such a source by passive and active systems. Before implementing such Passive and Active applications of solar energy as discussed in Chapter I, importance first and foremost has to be given to the location, the prevalent climatic conditions and insolation contribution, since such conditions if favourable could stimulate strongly the potential for the utilization of such solar applications. In fact Chapter II ‘Meteorology and Solar Radiation in Malta’ provides such information on local meteorological conditions such as air temperature, air humidity, winds, sunshine hours, and most importantly the Radiation Climate in the Maltese Islands. Such information as presented shall offer valid assistance for analysing those solar systems active or passive which could be installed for various domestic needs. Chapter III ‘Solar Flat Plate Collectors and their use for Domestic Solar Water Heating’ is concerned with one particular and important application of solar energy for Malta. This chapter describes the solar water heaters, their basic parts, and technique involved for producing hot water by two important types of solar systems – the Thermosyphon and the Forced Circulation. This chapter includes also information on the Austrian-Maltese Research Centre and its functions. A method of estimating the useful output of a particular domestic solar water heater, assembled locally and operated by the thermosyphon system is presented in Chapter IV, dealing with the ‘Economic analysis of a Domestic Solar Water Heater’. Obtaining the necessary data on the thermal performance of the system together with data on annual insolation, I could then proceed to the economic evaluation of the solar device by the present worth, annual cost and break-even point methods in comparison to the electric water heater. Described in this chapter is the theoretical aspects and technique of the method used for cost analyses together with the derivation of the various formulae used. This analysis can be considered as a case study, an application of the principles discussed in the context of conditions predominant in Malta.