Overcoming existent barriers to support blue economy growth

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On a new method to design solar photovoltaic systems in renewable energy communities: The case of Culatra Island (Ria Formosa, Portugal)

Publication . Ewart, M.; Santos, J.; Pacheco, A.; Monteiro, Jânio; Sequeira, Claudia

Islands must reach sustainable lifestyles by improving resources management and by getting accustomed to renewable energy sources. Culatra, a small Portuguese island, is actively increasing renewable energy penetration into local processes in order to be the first 100% sustainable Portuguese territory by 2030. Based on the electric consumption of Culatra, the objective of the present study is to project a photovoltaic unit composed of several sub-fields, each with a distinct orientation, in order to increase the self-consumption ratio while at the same time reducing the surplus of energy production, assessed by the self-sufficiency ratio criteria, resulting in a lower levelised cost of energy of the power system. To achieve this, MATLAB's implementation of a genetic algorithm was used to find the optimised set of orientations for a given load profile. The results indicate that it is possible to optimise the photovoltaic plant to reach a more continuous electricity generation through daytime, reducing the storage needs and increasing the value of photovoltaic systems. The method can be extended to other locations or demand curves, assisting on comparing different energy management strategies, and their respective advantages and disadvantages.

2023Journal article

Restricted access

Enhancing efficiency in solar non-intrusive desalination: solar still prototype optimization in Southwest Europe

Publication . Pacheco, André; Sequeira, Claudia; Silva, Manuela Fernanda Gomes Moreira da; Serrão Sousa, Vânia

Access to freshwater is a pressing global challenge. Despite being irreplaceable freshwater is an increasingly scarce resource, especially in regions as Southern Europe, due to high human pressure and climate change. Solar desalination presents a low impact solution to produce freshwater from seawater, particularly in sun-rich regions. The main goal of this study was to develop a modular solar desalination system based on a non-intrusive approach, with simple assemblage, installation, and maintenance, to produce freshwater for non-potable purposes. The modular design was chosen to allow scalability and adaptability, enabling effective response to variable water demands in small island communities. The case study is a small island from Algarve, Portugal (Southwest Europe). The study evaluates the performance enhancements accomplished by transitioning from an initial prototype solar desalination unit, smaller and with a simple design, to an enhanced pilot-scale system designed to improve efficiency and water output. The research showed that both systems exhibit a high conductivity removal (higher than 99 %), demonstrating the potential of this technology to produce freshwater from seawater, delivering high-quality desalinated water, across different seasons. Prototype 1 demonstrated limited productivity, around 0.45 L/day.m2, while pilot-scale unit presented a productivity of approximately 6 L/day.m2 in summertime. This substantial improvement reflects the design modifications implemented in the pilot-scale unit, positioning it as a valuable option for water desalination in regions with abundant solar resources. These findings confirm the strong potential of solar desalination as a non-intrusive and effective solution and lays the groundwork for future advancements, focusing on maximising efficiency by exploring innovative materials to enhance solar energy absorption and optimizing operational conditions.

2025-04Journal article

Open access

Comparative viability of photovoltaic investments across european countries using payback periods and the levelized cost of energy

Publication . Carvalho, Jailson Pereira de; Lopes, Eduardo B.; Santos, Joni; Monteiro, Jânio; Cabrita, Cristiano Lourenço; Pacheco, André

Electrical grids are undergoing a transformation driven by the increasing integration of renewable energy sources on the consumer side. This shift, alongside the electrification of consumption—particularly in areas such as electric mobility—has the potential to significantly reduce CO2 emissions. However, it is also contributing to a rise in electricity prices due to growing demand and infrastructure costs. Paradoxically, these higher prices serve as a catalyst for further investment in renewable energy technologies by reducing the payback periods of such systems. Recent European legislation has accelerated this transformation by mandating the liberalization of energy markets. This regulatory shift enables the emergence of prosumers—consumers who are also producers of energy—by granting them the right to generate, store, and trade electricity using the existing distribution grid. In this new landscape, photovoltaic systems represent a viable and increasingly attractive investment option for both households and businesses. This study presents an economic evaluation of photovoltaic system investments across different European countries, focusing on key indicators such as payback periods and the impact of local solar irradiation on the resulting electricity price. The analysis provides insight into the varying economic feasibility of distributed solar energy deployment, offering a comparative perspective that supports both policymakers and potential investors in making informed decisions about renewable energy adoption.

2025-09-03Journal article

Open access