Increasing energy production through renewable sources is a challenge for islands. This paper investigates the potential of hydropower as a renewable energy source for islands in the Macaronesia region, which includes the Azores, Madeira, Canary Islands, and Cape Verde. Ecological transition towards renewable energy sources is crucial for these islands due to their current dependence on imported fossil fuels and their remoteness. The methodology used in this paper combines a SWOT analysis with a review of relevant literature. The SWOT analysis evaluates the Strengths, Weaknesses, Opportunities, and Threats associated with hydropower development on each island. The results show that each island has unique characteristics that influence its hydropower potential. The Azores has existing mini-hydropower plants and opportunities for pumped storage systems due to its rainfall and volcanic features. Madeira also utilizes hydropower, including the world's first underground pumped storage plant (UPHS) in Socorridos. However, limitations exist due to the mountainous terrain and competition for water resources. The Canary Islands showcase the success story of El Hierro Island, which significantly increased renewable energy penetration through a wind farm and pumped storage hydropower system. The topography and lack of rainfall on Cape Verde make the development of hydropower a significant challenge and, as a result, the focus has shifted to wind power. The study concludes that hydropower can play a significant role in the ecological transition of these islands. However, careful planning and consideration of environmental factors are necessary to maximize the benefits and minimize the potential drawbacks. The paper emphasizes the importance of island-specific assessments and exploring opportunities for pumped storage systems. Doi: 10.28991/CEJ-2024-010-07-019 Full Text: PDF

The water consumption of hotels varies greatly from one to another and can depend on many factors such as category, country, climate, size, hotel facilities (spas, swimming pools, gardens, kitchens, laundry, etc.), occupation, and so forth. Five-star hotels are responsible for large amounts of water consumption in the hotel industry, and this has an impact on water consumption in the Canary Islands. This study shows the evolution of water consumption for the period 2014–2019 in a five-star luxury hotel in Tenerife. Results show an average water consumption of 700 litres per guest and night, with minimums around 600 and maximums over 1000. The hotel has its own desalination plant and introduced water saving measures progressively over the last few years, achieving a very significant reduction in water consumption and energy costs. Water improvements improve the energy efficiency of the building, as well as having a positive impact on customers’ opinions.

Islands are isolated systems that depend on maritime trade for their subsistence. Efficient, durable and structurally reliable port infrastructures are essential for the economic and social development of islands. However, not all port infrastructures are designed in the same way. They can vary, depending on whether they are built on continental land, built on non-volcanic islands or built on volcanic oceanic islands (such as the Canary Islands, Spain). The latter islands are the subject of this study due to their specific features, construction difficulties and the importance of sound maritime infrastructures. The maritime climate of an area consists of the wave and storm regimes that affect it and, from these, the coastal dynamics and coastal formations of that area can be studied. For this reason, historical data were collated on significant directional wave heights from 1958 to 2015 from several WANA-SIMAR points in the virtual buoy network of State Ports of Spain located near the Canary Islands. These data have been studied to obtain the maximum directional wave heights (Hs) at each point. With this analysis, we have obtained useful summary tables to calculate wave height by a graphic method that transforms the distribution function into a line drawn on probabilistic paper, using reduced variables. This enables adjustments to be made by linear regression and minimum square methods to facilitate planning and design of maritime infrastructures in a reliable way. Doi: 10.28991/CEJ-2022-08-01-02 Full Text: PDF

Insularity presents several challenges in the development of Europe’s outermost regions. In the case of the Canary Islands, one of these challenges is waste management, which faces a series of difficulties inherent to territorial disparities, including land use and availability, a high percentage of protection, a large number of annual tourists and a high level of product imports. The archipelago is made up of eight islands, and waste management is significantly different in the two capitals, Tenerife and Gran Canaria, and the rest of the smaller islands. European targets for adequate waste management have not been achieved in those areas. As an example, only 16% of the collected waste is recycled currently, mainly due to a lack of infrastructure and a lack of agility on the part of the corresponding institutions. There is also pressure exerted on this sector by tourism, which accounts for approximately 40% of employment in two of the islands. As a general conclusion, valorized waste management is proposed, where the use of by-products, such as biogas or compost is implemented in sectors where they can be used, i.e., as electricity, potentially of 19 GWh/year, and agricultural supply, thus promoting recycling and the circular economy in the Canary Islands.

Emerging pollutants (EPs) are substances present in wastewater that have not been studied, previously, leading to ambiguity in regulations for their presence in water resources. Territories that are highly dependent on groundwater resources are at a high risk of suffering the consequences of EP contamination due to their dependence on good quality groundwater for agriculture, drinking, and other uses. A relevant example is El Hierro (Canary Islands), which was declared a biosphere reserve by the UNESCO in 2000 and is almost completely powered by renewable energies. Using high performance liquid chromatography-mass spectrometry, the concentrations of 70 EPs were assessed at 19 sampling points on El Hierro. The results indicated that no pesticides were present in groundwater; however, varied concentration levels of ultraviolet (UV) filters, UV stabilizers/blockers and pharmaceutically active compounds (PhACs) were found, with La Frontera being the most contaminated municipality. With regard to the different installation types, piezometers and wells were the ones showing the highest concentrations for most EPs. Interestingly, the depth of sampling correlated positively with EP concentration, and four different clusters virtually dividing the island into two areas could be identified based on the presence of each EP. More studies should be performed to ascertain why a few of the EPs showed considerably high concentrations at different depths. The results obtained highlight the need to, not only implement remediation measures once EPs have reached the soil and aquifers, but also to avoid their incorporation into the water cycle via homes, animal husbandry, agriculture, industry, and wastewater treatment plants (WWTPs).

Emerging pollutants (EPs) include a wide array of chemical compounds, as well as some microorganisms, which presence was unknown or unmeasurable until recently, or have recently started to be considered a threat towards the environment or animal and human health. No clear or homogeneous regulations exist for their measurement or control, and efforts should be made to assess their presence and offer solutions for their safe management, as well as to achieve an optimal protection of water resources. A previous study performed by our research group thoroughly studied a wide profile of EPs in El Hierro Island (Canary Islands) for the first time. Now, we present the study of the same panel of 70 EPs in La Palma Island (Canary Islands). 14 samples were collected in 2021, at different locations in La Palma island, representing seven municipalities (Los Llanos de Aridane, Santa Cruz de la Palma, El Paso, Breña Baja, Tazacorte, Barlovento and Fuencaliente) and four installation types (Piezometers/Wells, Wastewater Treatment Plant (WWTP), Water Gallery and Water Springs). High performance liquid chromatography-mass spectrometry (HPLC-MS) was performed to analyse the EP array, which included five chemical families: UV filters, UV blockers/stabilizers, parabens, Pharmaceutical Active Compounds (PhACs) and pesticides. Subsequently, a comprehensive descriptive and statistical analysis, including different tests was performed on the data obtained. Heterogeneous concentration levels of the EPs studied were found based on municipality and installation type among the island, with some of the PhACs and UV blockers/stabilizers showing very high levels, especially at Breña Baja and wastewater treatment plants (WWTPs). It is worth noting that some of the samples comprised within the WWTPs category were collected outside the treatment plant, after water has been treated, so they should not bear dangerous concentrations of any hazardous compound. The high presence of two pesticides, imidacloprid (ranging from 68.7 to 24,896.5 ng⋅L^-1) and acetamiprid (ranging from 1010.7 to 5168.1 ng⋅L^-1) was worth highlighting too. In addition, three EP concentration clusters were found to virtually divide the island based on mathematical percentiles of EP mean concentrations, which can help gain more insight into the contamination status of the island and measures that could be taken for their management. Finally, a comparison between La Palma results and the profile observed at El Hierro by our research group was presented. Altogether, the study performed calls for a need to take actions towards avoiding entrance of EPs in the water cycle, and not just focusing on remediation strategies once they have reached the groundwater, freshwater or soil.