https://www.um.edu.mt/library/oar/handle/123456789/1181 2026-10-01T03:00:08Z https://www.um.edu.mt/library/oar/handle/123456789/149302 Title: An integrated frequency-domain modelling framework for coupled response analysis of pontoon-truss offshore floating photovoltaic systems Authors: Luo, Wenping; Zhao, Yiwei; Zhang, Xiantao; Tian, Xinliang; Li, Xin; Bugeja, Ryan; Mule' Stagno, Luciano Abstract: Pontoon-truss offshore floating photovoltaic (PT-OFPV) systems with higher freeboard have been widely adopted in conceptual designs and prototype tests, effectively reducing the direct wave impact on electrical components. To provide an efficient evaluation of dynamic responses and structural integrity during preliminary design stages, this paper proposes a frequency-domain modelling framework for PT-OFPVs by combining finite element (FE) and discrete module beam (DMB) methods. The structure is divided into two parts and modelled separately according to their exposure to external loads. The superstructures above water are modelled using FE, while the substructures below water are modelled using DMB. Hydrodynamic loads are obtained through multi-body potential theory and applied to lumped mass points in the DMB model. Wind loads are incorporated via a frequency-domain drag formulation and applied to the deck nodes in the FE model. The complete numerical model is then established by coupling these two parts through shared interconnecting points, in combination with a linear mooring system. Then, several cases are simulated to validate the reliability of the potential-theory solution and the proposed coupled modelling framework. Subsequently, the dynamic responses of a PT-OFPV concept under regular and irregular environments are analyzed, including the effects of structural and mooring properties. A structural optimization strategy under the FE-assisted framework is also developed and demonstrated on the PT-OFPV platform. Results show that the proposed modelling framework accurately predicts motion responses compared with model tests. Moreover, stress analysis indicates that vertical trusses and pontoon connections experience the highest loads. The structural optimization reduces the total platform mass by approximately 29.4% and the maximum stress by about 31.8%, demonstrating the feasibility of the proposed optimization strategy. 2026-01-01T00:00:00Z https://www.um.edu.mt/library/oar/handle/123456789/148518 Title: Green bonds : reconciling market constraints and policy incentives in the small state of Malta Abstract: This study explores whether, and under what conditions, green bonds can realistically help finance the net-zero transition in a small state context, using Malta as a focused case study. Although global green bond markets have grown quickly and EU sustainable finance rules are raising expectations on disclosure and credibility, smaller member states face practical constraints that can limit issuance. These include limited issuer scale, thin secondary markets, a retail-heavy investor base together with relatively high fixed costs for developing a framework, securing external review, and maintaining reporting over time. The research therefore investigates when green bonds add practical value compared with other financing channels and what enabling measures would be needed for green bond issuance to work at scale in Malta. The study combines a policy and institutional analysis of EU sustainable finance requirements and their translation into Maltese practice with evidence from semi-structured interviews across regulators, market intermediaries, public entities, and financial institutions. The findings suggest that Malta’s sustainable finance architecture is increasingly aligned with EU objectives, but that capacity, data availability, verification readiness, and market depth remain binding constraints. Interview evidence also points to a consistent commercial challenge: without complementary incentives or risk-sharing, green labelled issuance is unlikely to compete on price with established funding channels, and many investors, especially price-sensitive retail participants, do not attach additional value to a green label unless credibility is strong and liquidity is credible. The study argues that green bonds can still play a useful role in Malta, but mainly where the instrument is adapted to small market realities. This includes aggregation structures that bundle smaller projects into investable portfolios; quasi-sovereign or public first-mover issuance to create benchmarks and build confidence; and policy-backed mechanisms (such as guarantees, interest-rate support, and verification/reporting support) that reduce execution risk and lower total issuance costs. The study concludes with market and policy level recommendations aimed at reconciling EU credibility requirements with Malta’s market structure, improving feasibility while protecting transparency and pursuing economic and climate change impact. Description: M.Sc.(Melit.) Sust.Energy 2025-01-01T00:00:00Z https://www.um.edu.mt/library/oar/handle/123456789/146869 Title: Comparing photoluminescence imaging and microwave detected photoconductivity for measuring recombination lifetimes of silicon wafers Abstract: This study investigates the correlation between recombination lifetime and photoluminescence (PL) in silicon solar cells, aiming to evaluate the reliability of Photoluminescence Imaging (PLI) as compared to the well-established Microwave Detected Photoconductivity (MDP) technique. Recombination lifetime is a critical parameter influencing solar cell efficiency, as it determines how long charge carriers persist before recombining. Using both MDP and PLI tools, the recombination lifetimes and corresponding PL grey values of monocrystalline silicon wafers were measured under various thermal and contamination conditions. Heat treatments at 800°C and 950°C, along with deliberate contamination using a copper coin and latex gloves, were employed to produce a wide range of recombination activity across the samples. Data were analysed using ImageJ to correlate PL grey values with MDP-measured lifetimes. A linear relationship of the form Y = 0.0090X, where Y is the recombination lifetime and X is the grey value, was established through regression analysis. Results revealed a consistent relationship between the two measurement techniques, validating the potential of PLI as a rapid and non- destructive proxy for lifetime assessment. The findings support the development of cost-effective and efficient quality control methods in photovoltaic manufacturing by leveraging the complementary strengths of both PLI and MDP. Description: M.Sc.(Melit.) 2025-01-01T00:00:00Z https://www.um.edu.mt/library/oar/handle/123456789/146139 Title: Evaluating sociotechnical factors influencing the feasibility of vineyard photovoltaic integration in Malta Authors: Rexhausen, Aron; Rothstein, Benno; Yousif, Charles Abstract: This study investigates the feasibility of viticultural photovoltaics (Viti-PV) in Malta — a small European island state in the Mediterranean — through a mixed-methods approach, combining a standardised questionnaire (n= 13 viticulturists) with expert interviews involving stakeholders from viticulture, energy and policy. Results show that while Viti-PV offers tangible benefits such as shading, reduced irrigation needs and income diversification to this sunny, warm and relatively dry island, adoption is constrained by high investment costs, regulatory prohibitions and concerns over landscape impacts. For policy and practice, the findings highlight the necessity of tailored financing models, regulatory adaptation and participatory pilot projects to build evidence and stakeholder confidence. Viti-PV can contribute simultaneously to renewable energy targets and viticultural climate resilience, but its implementation depends on coordinated support across technical, economic and institutional dimensions. 2026-01-01T00:00:00Z