/library/oar/handle/123456789/6579 2025-12-27T04:08:52Z /library/oar/handle/123456789/77968 Title: Testing, evaluation and optimisation of the performance of a stand-alone photovoltaic system in Malta Abstract: The technology of photovoltaics is constantly progressing and likewise its market. It is envisaged that by the turn of this century, photovoltaic (PV) power production will be cost effective for many applications. It is well known that Malta has an abundance of sunshine, however, measurement of solar radiation has long been abandoned. At the same time, there is lack of information on the possible outcome of the use of PV systems for electricity production. In this work, the measurement of solar radiation has been re launched together with a study of the performance of a 1.2 kWp stand-alone photovoltaic, (PV) system, with battery storage. Sixteen months of data has been collected and analysed in accordance with the guidelines set by the Joint Research Centre - Ispra Establishment. For this period, the mean global horizontal radiation was found to be 4. 7 kWh/m2/day and the mean global radiation on the plane of the modules (36° to the horizontal), was 5.24 kWh/m2/day. In order to study a PV system properly, a full knowledge of the characteristics of solar radiation and solar cells become essential. These have been described in the appendices. An overview of the instruments used for solar radiation measurements was also presented and a comparison was made between the different types of PV cells and silicon cells. A.conclusion has been reached to use silicon cell-based pyranometers (solarimeters) for measuring solar radiation in studies related to photovoltaic systems. A description of the design of the stand-alone PV system was presented together with the · precautions solutions were offered lo the problems encountered during data collection. The analysis of data yielded a wealth of information on the performance of the PV system in Malta. Load management was identified as a key factor to the optimum utilisation of such a system. Description: M.PHIL. 1995-01-01T00:00:00Z /library/oar/handle/123456789/6658 Title: Analysis of the current energy support mechanism for low income groups And investigation of alternative energy support measures to support vulnerable consumers in Malta Abstract: In 2014, about 25,276 Maltese families were registered as fuel poor and they were provided with an ‘energy benefit’ aimed at mitigating the effect of expenditure on water and electricity bills [1]. This financial assistance cost the taxpayers approximately €5 million per year [2]. In the light of this scenario, new strategies to tackle such a financial burden and thus reduce the fuel poverty need to be evaluated. These are precisely the objectives of this project which consists mainly of an in-depth analysis of the energy consumption patterns of vulnerable consumers, the modelling of a proposed definition appropriate to the local context, and an analysis of the impact that the application of this definition will have with respect to the present situation. In the Maltese legislation, although there is no formal definition for the vulnerable consumers, a combination of expenditure and consensual approaches are being applied in order to identify those consumers that are deemed to be in need of, and eligible for some form of financial assistance. The current system suffers from a number of shortcomings and therefore it was important to identify a more consistent and a narrower definition for ‘the vulnerable consumer’. The proposed definition is based on Hills’ methodology, taking into account the interaction between two components, namely low income and high energy costs (LIHC indicator). When these two factors occur simultaneously, the result greatly impinges upon the household’s vulnerability, and it is likely to push the household below the poverty line. From the detailed analysis carried out, the ‘Estimated Income Indicator threshold’ and the ‘Estimated Energy Indicator threshold’ were determined as 7,956 euros per person per year and 700 euros per person per year respectively. Based on these results, the electricity consumption threshold was taken as 5.0 kilowatt-hour (kWh) per person per day. To define the applicability of the proposed definition/thresholds, 600 invitation letters to perform energy audits were sent to the households that are currently eligible for the energy benefit. About 122 house visits were completed to analyse 61 vulnerable consumers’ residences electricity consumption. Energy audit data was then analysed and amongst various results, it was found that 61.5% of the visited households spend more than 9% of their income on the utility bill whilst 86.5% of the visited households consume more than 5kWh per person per day. Based on these actual results, alternative solutions were put forward, making up the last phase of this study. From the energy audit results, it was determined that the most common equipment used in the audited households and which has direct implications on the consumers is the ‘Water Heating Equipment’. A number of solutions were identified and analysed in order to find the most economically feasible method to lift the identified vulnerable households out from fuel poverty. It results that with the installation of a 3kW peak PV system to all eligible vulnerable households, about 7,328 consumers will no longer classify as fuel poor whilst the net calculated savings over a period of 20 years can reach 13.5 million euros. Adopting the proposed definition would have implications on the manner in which households which are identified as being energy vulnerable, will be provided with the required assistance, since each vulnerable household has its particular circumstances and may therefore be considered as a case study on its own. The interplay between low income and high energy costs implies that more appropriate assistance should focus on reducing the consumption level of the vulnerable consumers. In this way one would be directly addressing the root cause rather the resulting symptoms characteristic of the vulnerable households. Description: M.SC.SUS.ENERGY 2015-01-01T00:00:00Z /library/oar/handle/123456789/6627 Title: Design and testing of a low-level concentrator Abstract: One way to promote the increased use of renewable energy technology for the purpose of energy production is to drive down the cost of renewable energy on par or even less than energy derived from fossil fuels. One technology which has the potential to meet this requirement is concentrated photovoltaic technology. As such, the scope of this dissertation was to investigate photovoltaic concentrator systems with particular note to low-level concentrators. As part of the study, a prototype system was designed and constructed in order to investigate its performance. The prototype system consisted of a concentrator module which holds up to four Fresnel lenses that concentrate sunlight on to the receiver. The module is mounted onto a dual-axis tracker which maintains its orientation directly perpendicular to the incident radiation from the sun. An experiment carried out in this study over a number of days was used to compare the energy delivered by four identical poly-crystalline solar cells subjected to different conditions. The cumulative energy output of a cell fixed in a south-facing orientation, and inclined at 45∘, was used as a reference to calculate the percentage change in the cumulative energy output of the three other cells: one tracking the sun on both axes and another two receiving concentrated illumination through the use of the Fresnel lenses. These last two cells, which tracked the sun as well, were mounted on different heatsinks to investigate the effect of heat on cell performance. The results showed that the cell mounted on the large heatsink, and subjected to concentrated illumination, performed the best with an average percentage increase of 63.60% over the cumulative energy output of the non-tracking cell. Description: M.SC.SUS.ENERGY 2015-01-01T00:00:00Z /library/oar/handle/123456789/6626 Title: Comparison of floating offshore wind turbines with floating solar PV in central Mediterranean waters Abstract: Malta, being a very small and densely populated island in the central Mediterranean, has limited land space and the territorial waters are mostly too deep for conventional offshore wind farms to be constructed. This paper presents a preliminary engineering analysis to develop two cost-optimized structures to support (1) a multi-megawatt scale wind turbine and (2) a solar photovoltaic farm with the same energy production as that of the single wind turbine. The primary objective of this work is to determine the most economically feasible option for harvesting renewable energy at sea: offshore wind or offshore solar photovoltaic energy. Reviewing the available technologies enabled the selection of the most appropriate conceptual design for each of the energy generation platforms using basic engineering theory. Calculations were carried out on the general arrangement and overall hull design taking into consideration wind and wave loading, weight, buoyancy and stability, static analysis, mooring arrangement and cost. The support structure has been proposed according to the guidelines given by offshore wind turbine standards and reflects typical local climatic conditions in the centre of the Mediterranean Sea. Load calculation were undertaken at wind speeds of 25 ms-1 and at 42.5 ms-1, which imply operational and extreme wind conditions, respectively. Hydrodynamic loads under extreme wave conditions were also modelled. The calculations were carried out through a simple iterative model which was set up using the solver algorithms of Microsoft Excel. STAAD Pro ver8i software was used to undertake static analysis simulations and determine deflections, compressive, tensile and shearing forces and bending moments. The final part of the analysis consisted of formulating a cost model for each of the two platform types and estimating the levelised cost of energy (LCOE) for both floating wind and solar PV in the deep offshore environment. Description: M.SC.SUS.ENERGY 2015-01-01T00:00:00Z