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UNIVERSITY OF MALTA 
INSTITUTE FOR ENERGY TECHNOLOGY
Triq il-Barrakki, Marsaxlokk, MXK 1531, Malta
TEL: (+356) 21650675/21652249      FAX: (+356) 21650615

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Wind Resource Assessment for Malta (Nov. 1998)

R. N. Farrugia
 

Evaluation of long-term wind records taken at the Meteorological Office Luqa, yields details on characteristics particular to the local wind climate.  Features such as the diurnal variation, seasonal, and annual trends of wind parameters are fully exposed on evaluating this database.  As wind is site-specific, new wind measurement strategies are devised so as to evaluate other sites and yet exploit the potential of this long-term data set.  Recording devices and ancillary equipment have been erected at selected candidate sites to measure wind variables at different heights above ground level.  This methodology enables the wind regime of such locations to be compared and ‘calibrated’ against the long-term database.  This analysis indicates that certain sites possess wind characteristics in excess of those recorded at Luqa.

The wind conditions at candidate sites are also determined by mathematical modelling.  The WASP program is used to extrapolate the long-term wind climate from the Meteorological Office to these same candidate sites.  This confirms that WASP generates reliable results in the local context.  Wind maps for the islands show the long-term predicted mean wind speeds and power densities for the Maltese islands, whilst at the same time highlighting areas suitable for sustainable wind generation.

A case study for a 5.4 MW wind farm at one of the potential sites is also presented.  Wind characteristics taken on site and WASP-generated results facilitate estimates of wind turbine energy yield.  Parameters other than the wind potential such as the available land area, the wind turbine array layout, and other related factors are also quantified and put in perspective with this particular location in mind.  An economic analysis is finally presented so as to determine a realistic price for wind-generated electricity at this specific location.
 
 

Testing, Evaluation and Optimisation of the Performance of
a Stand-alone Photovoltaic System in Malta (Feb. 1995)

C. Iskander Yousif

Malta (latitude 35° 50' N, longitude 14° 26' E) depends solely on the importation of fossil fuels to provide for the islands’ needs for energy. Due to the expansion of the industrial sector and the increase in the quality of life of the Maltese society, the need for electricity is increasing at the rate of 8.7% per annum, which is more than three times the world average and it is predicted to continue increasing at this rate for the next twenty years.

Besides the well-known advantages of photovoltaic (PV) solar modules for electricity generation - non-polluting, silent, reliable, modular, having a stabilised operation during their long lifetime of more than twenty years, having no moving parts and requiring minimal and technologically simple maintenance - the use of such systems as a subsidiary source of electricity in Malta, could lower the national energy bill, reduce pollution, prolong the life of the existing power stations, and relieve the summer peak demand on the electric utilities. Certain applications are already well suited for direct coupling to PV modules such as water pumping and air-conditioning, whose use increase with higher solar radiation. Also, the international policies and commitments for the protection of the environment prompts the country to promote the use of renewable energy.

Encouraged by the fact that the amount of solar radiation incident in Malta is abundant, averaging to about 5 kWh/m² per day on a horizontal surface and that the total amount of flat roof area, that is suitable to place the PV modules is at least 10 000 000 m², an interest in tapping this energy becomes obvious.
This thesis describes the first research work being done in Malta, aiming at testing and optimising the performance of a photovoltaic system under the local weather. As a start, it was thought to design and install a stand-alone PV system with battery storage. Though a grid-connected system could have been more adaptable to Malta, however, such a system required changes in the national energy legislations which was not possible at the time.

Nevertheless, the application of PV stand-alone systems could be useful in Malta for street lighting, to provide energy to boats and for emergencies. It was realised that before applying such a relatively expensive technology on a large scale, a proper scientific evaluation of the performance of such systems and their cost had to be carried out based on the local conditions.

Another important aim of this study is to restart the collection of solar radiation data to serve as a data base for future applications of solar technology.
This study is divided into five chapters:

The first chapter describes the design and installation of the PV system. A full description of the monitoring system is also given as well as the experience gained during installation. In the second chapter, the operation of the system is described together with the maintenance carried out on the different balance of system components.

The analysis of the collected data and the presentation of results are described in Chapter Three, while a cost evaluation and a sensitivity analysis are presented in Chapter Four. Finally, Chapter Five describes the conclusions and recommendations of this study.

Four appendices have been included that describe the nature of solar radiation and methods of measurement, the characteristics of solar cells, the tables and programmes prepared during this study and the relevant information collected for the project, respectively.

E-mail us at ietmalta@um.edu.mt