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Today, solar thermal systems are well established worldwide with an enormous potential for energy production and for high contribution to the future green energy system. Solar domestic hot water systems with natural circulation are most favorable in areas with a mean annual sum of global radiation on a horizontal surface above 1800 kWh− 2 year− 1 and with collector areas up to 10 m2. Forced circulation systems for flat-type solar collectors could be useful in colder climates and for large systems. The application of more complex solar collector technologies depends on the possible demands for higher temperature levels. Several examples concern some industrial applications, whose heat demands could now be met through solar energy. In all the cases, the next challenge is to swiftly make cost-effective all such devices and technologies.

This research aims to propose and evaluate an integrated adaptive system consisting of individual movable modules for the improvement of indoor environmental conditions. The system was evaluated by means of a natural lighting analysis simulation using Ecotect v5.2 and Desktop Radiance v1.02. Daylighting performance indicators, i.e. daylight factor (DF) and uniformity daylight factor (UDF), were calculated for various geometrical configurations. The analysis suggests that the integration of the system in appropriate geometrical configurations maintains high percentages of the plan area exceeding 2% DF, while it drastically increases UDF above the threshold of 0.40. Moreover, an in-depth analysis of natural lighting levels was performed for south-facing spaces during different periods of the year and hours of the day. In the majority of the cases under study, the proposed system maintains a high percentage of the plan area with lighting levels above 500 lux, while it significantly decreases the percentage of area exceeding 3000 lux and thus minimizes the possibilities of glare issues. The research study confirms the positive contribution of the proposed system as a natural lighting regulation system, while it establishes the concept of prosthetic renovation as a renewable energy strategy for the improvement of indoor comfort of existing buildings. 115 620 633

There is a growing number of methods to assess data-limited stocks. However, most of these methods require at least some basic data, such as commercial catches and life history information. Meanwhile, there are many commercial stocks with an even higher level of data limitation, for which the inference of stock status and the formulation of advice remain challenging. Here, we present a stepwise approach to achieve the best possible understanding of extremely data-limited stocks and facilitate their management. As a case study we use a stock of the shrimp Plesionika edwardsii (Decapoda, Pandalidae) from the eastern Mediterranean Sea, where the only available data was a sub-optimal sample of length frequencies coming from a small-scale trap fishery. We use a suite of different methods to explore and process the data, estimate the growth parameters, estimate the natural and fishing mortalities, and approximate the reference points, in order to provide a preliminary evaluation of stock status. We implement multiple methods for each step of this process, highlighting the strong and weak points of each one of them. Our approach illustrates the better insights that can be gained by applying ensembles of models, rather than a single ‘best’ model when working with limited data of poor quality. The stepwise approach we propose here is transferable to other extremely data-limited stocks to elucidate their status and inform their management. © Copyright © 2020 Pantazi, Mannini, Vasilakopoulos, Kapiris, Megalofonou and Kalogirou.

The Collective Article on "New Mediterranean Biodiversity Records" offers the means to publish biodiversity records in the Mediterranean Sea. The current article presents new biodiversity data information on 18 taxa (14 alien, 3 native and 1 cryptogenic species) belonging to 5 Phyla that are reported for 11 different countries listed according to their geographic position from the western to the eastern Mediterranean Sea. Algeria: the alien green alga Caulerpa taxifolia var. distichophylla and the heterobranchs Aplysia dactylomeda and Aplysia punctata are first reported from the entire country. France: a new record of the alien hydroid Porpita porpita is reported from the Corsican Sea, representing the second record of the species in the western Mediterranean Sea. Tunisia: the alien fish Scatophagus argus is reported from the Gulf of Gabes, probably representing an aquarium release. Italy: the well-established Mediterranean alien bivalve Malleus regula is first reported from the entire country. Slovenia: the alien marine bivalve Xenostrobus securis is reported for the first time from the entire country. Croatia: the alien gastropod Biuve fulvipunctata is reported for the first time from the country but also from the entire Adriatic Sea. Montenegro: the alien bivalve Rapana venosa is reported for the first time from the Montenegrin waters. Albania: the well-established alien fish Lagocephalus sceleratus and the rare native shark Rhizoprionodon acutus are reported for the first from the entire country. Greece: the rare native ray Leucoraja circularis is reported for the first time from the Argolikos Gulf and for the first time for the entire country its identification is confirmed morphologically and molecularly; additional records of the alien nomad jellyfish Rhopilema nomadic document its expanding distribution, while the occurrence and the alien fishes Sillago suezensis and Pomadasys stridens are reported for the first time from Hellenic waters. Turkey: additional records of the Egyptian Prawn Metapenaeopsis aegyptia are reported with some biological information. Cyprus: the alien fish Variola louti is reported for the first time for the entire Mediterranean Sea, probably released from an aquarium, while the alien moon crab Matuta victor is reported for the first time from the entire country.

In building-integrated photovoltaic (BIPV) systems, PV panels and the façade or roof of the building are separated with an air gap, with openings in the bottom and top, to circulate the air and cool the PV panels to avoid efficiency loss and increase of the building’s cooling loads in hot climates. The natural ventilation of the air gap has several advantages in comparison with the mechanical, such as the avoidance of the energy cost for the fan’s operation, noise, space requirement for the fan installation, maintenance. One of the most important parameters to be investigated in order to have a general view of the system’s performance prior or after the installation and avoid PVs and building’s overheating, is the air flow effect in the air gap, in terms of the convective heat transfer coefficients. In this study, a series of experiments on a custom made BIPV system were carried in real outside conditions as well as indoors with the use of a large scale solar simulator to measure the thermal characteristics of the system and its thermal behaviour. Indoor experiments were performed to avoid external disturbances from wind that occur outside. The experimental data are then used to estimate the convective heat transfer coefficients to fit the real conditions of the BIPV systems. Then two correlations are proposed for the estimation of the Nusselt number that fits best the thermal characteristics of a naturally ventilated BIPV system.

A novel trigeneration system based on the combined operation of an Organic Rankine Cycle (ORC) and an Ejector Cooling Cycle (ECC) for industrial waste heat recovery is simulated. The influence of different operational parameters, such as working fluid selection, pressures and temperatures on the system performance is investigated. Furthermore, special focus is given on the selection and design of key equipment components, which include the heat exchangers, the expander and the ejector. Finally, a detailed techno-economic evaluation of the system for its application for waste heat utilization from an existing glass manufacturing plant is carried out. The electrical efficiency of the system was estimated equal to 5.7 %, with the COP of the trigeneration system amounting to 10.72 %. The payback period was estimated to be less than 5 years, with an internal rate of return equal to 27 %. Nevertheless, despite the attractive economic competitiveness of the system, significant operation limitations may arise due to its complexity.

Energy use in buildings represents 40% of the total primary energy used in EU and therefore developing effective energy alternatives is imperative. Solar Energy Systems (STS) will have a main role to play as they they contribute directly to heating and cooling of buildings and the provision of domestic hot water. STS are typically mounted on building roofs with no attempt to incorporate them into the building envelope, creating aesthetic challenges and space availability problems. The actions will foster and accellerate long-term development in STS through critical review, experimentation, simulation and demonstration of viable systems for full incorporation and integration into the traditional building envelope. Viable solutions will also consider economic constraints, resulting in cost effective Building Integrated STS. Additionally factors like structural integrity, weather impact protection, fire and noise protection will be considered. The most important benefit of this Action is the increased adoption of RES in buildings. Three generic European regions are considered; Southern Mediterranean; Central Continental and Northern Maritime Europe, to fully explore the Pan-European nature of STS integration. The Action consortium presents a critical mass of European knowledge, expertise, resources, skills and R&D in the area of STS, supporting innovation and conceptual thinking.

Renewable energy is important nowadays, not only as an environmental scientific issue, but as an obligation with regard to the European regulations. As a result, scientific interest has increased towards the improvement of the different renewable energy technologies and their optimum utilization in different applications. Initially the paper reviews previous studies regarding the optimum utilization and control of the renewable energy generation installed in buildings and in general in building energy management. The final section of the paper is a novel application related to the studies reviewed; however, this application uses a new and simple way to minimize the energy consumption levels through linear programming optimization.

The significance of the residential building sector in terms of energy consumption is well acknowledged. In this view the knowledge of the way the residential building stock of Cyprus behaves in terms of energy consumption is quite valuable since it will assist policy makers to formulate targeted measures aiming the improvement of energy efficiency and setting current legal standards and benchmarks in the energy performance certificate, a requirement of the 2002/91/EC Directive. Unfortunately, the existing knowledge on this subject is quite poor. As a remedy a research project supported by a national research grant is in operation since December 2008. This paper presents the outline, goals and methodology of this research project and the findings regarding the energy behaviour and other characteristics of the residential building stock of Cyprus. From the analysis of the results for 500 residential buildings, it seems that the energy demand and primary energy required is lower than that of other European countries. Moreover, it seems that the age of residential buildings has low correlation with the energy demand while in contrast with other Northern and Central European countries, it is clear that the contribution of cooling energy requirements to the overall energy demand is quite significant.

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During the last few years photovoltaic (PV) materials are increasingly incorporated (or integrated) into the construction of buildings for generating electrical power. This integration is done either on the facade or roof of the building. This integration creates also heat which if not removed can create cooling requirements in buildings, especially in summertime, whereas during winter this heat can be used effectively to cover part of the building heating load. Additionally, if this heat is not removed it will also lower the efficiency of the PV panels. Consequently there is a challenge to find solutions to remove this heat resulting from the building integrated PV (BIPV) panels. The aim of this study is to examine the effect of air flow in the air gap between the integrated PV panel and the building’s wall on the temperature of the PV panel. The examination of the effect of the air gap of a BIPV system is very important as it can lead to better understanding of the conditions that allow the higher efficiency of the PV panel and accordingly the increase of the efficiency of the BIPV system. Two different PV modules are examined; the one has a flat surface as the conventional PV panels and the other one has a repeated pi-section surface with different air gap widths through its length and thus different air velocity in the two types of sections. To formulate the heat exchange process for a fluid flowing between the PV panel and the building wall, time-dependent, partial heat transfer differential equations (PDEs) are used and solved with the COMSOL Multiphysics simulations program. Initially, the air-gap width is varied keeping a steady velocity, and subsequently the air velocity is varied keeping constant the air gap and the effect were studied in respect to the temperature of the PV-panel. The runs were carried out for three orientations for the panel facing east, south and west. For the PV module with the flat surface the simulations showed that for an air gap width of 0.02 m, an air velocity of 0.5 m/s can lower the mean temperature of the panel from 77°C to 39°C. For the PV module with non-flat surface (repeated pi-section) that has various air gap widths, the air velocity in the air-gap between the PV-panel and the building wall lowers the mean temperature of the panel by about 35°C allowing for a significant increase in its efficiency.

The present work reports on the extended distribution of nineteen species in the Mediterranean. These are: Upeneus pori (Fish:Turkey), Bursatella leachii (Mollusca, Opisthobranchia: eastern coast of Spain), Sparisoma cretense (Fish: Ionian coast of Greece), Pseudobryopsis myura (Chlorophyta:Turkey), Aplysia dactylomela (Mollusca, Opisthobranchia: Karpathos island, and Kyklades Archipelago, Greece), Asparagopsis armata and Botryocladia madagascariensis (Rhodophyta: South Peloponnesos, Greece), Oxynotus centrina (Fish: Greece), Caulerpa racemosa var. cylindracea (Chlorophyta), Stypopodium schimperi (Phaeophyta) Siganus luridus and Stephanolepis diaspros (Fish) Percnon gibbesi (Decapoda, Brachyura) (Kyklades Archipelago, Greece), Cerithium scabridum (Mollusca, Prosobranchia: Anavissos: Greece) and Cerithium renovatum (Mollusca, Prosobranchia: N. Kriti), Cassiopea andromeda (Scyphomedusa: Rhodos Island, Greece), Abra tenuis (Mollusca Bivalvia: Vouliagmeni Lake, Greece) Lagocephalus lagocephalus (Fish: Calabrian coast, Italy) and Plocamopherus ocellatus (Mollusca, Opisthobranchia: Iskenderun Bay, Turkey).

The objective of this study is to present a comparison between the measured and the calculated energy performance of dwellings. For this purpose, the energy consumption of ten dwellings is measured for one year. The added value of this work is that it is performed in a summer dominant environment. The energy needs of the same dwellings are also calculated by means of the methodology based on European Standards described in the CEN/TR 15615:2008 technical report. According to the findings of this study, a large gap exists between the calculated and the measured energy consumption of the examined dwellings. In order to evaluate the reasons for this deviation, a detailed analysis of the heating and cooling loads of the dwellings is performed. The intermittent heating of the building is found to be simulated accurately by the employed methodology, whereas the comparison between the calculated and the measured cooling loads reveals a large deviation of about 150%. Based on the findings of this study, a factor of 0.6 should be adopted in the case of cooling schedule, compared to the heating operation of the building.

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Presented at 4th International Conference on Sustainable Devlopment and Planning, 2009, 13 - 15 May, Cyprus This paper describes the work that will be done in a research project, which will facilitate the implementation of the EPBD through the calculation of the existing Cyprus Building Stock energy behaviour. This will be achieved through the selection of a representative sample of 500 housing units and the collection of data through questionnaires, followed by statistical analysis of the data and the interpretation of the results. The key parameters that will form the different clusters are climatological zone, type, age and size of each housing unit. The statistical interpretation of the collected dataset will provide insights with regards to the energy behaviour of the building stock for each class. The ultimate goal is to suggest the number of classes for the Energy Performance Certificate and the upper and lower energy consumption limits for each class. Moreover, the formulation of an energy behaviour map, the consideration of the historical development of the buildings behaviour and the improvement of the insulating materials and solutions, will lead to the readjustment of the values, particularly for the best two classes, so as not only to reflect today’s reality, but also to show the intent of the state to improve the level of the construction industry. In this study, the various types and quantities of thermal insulating materials utilized in Cyprus, for the time interval 01/01/08–30/09/08, are also reported. The data were extracted from applications made by individuals who claimed financial subsidy. A random specimen of 400 applications was evaluated: 55% refer to existing housing, and 45% to new buildings. The different kinds of materials used for insulating floorings, walls and roofs, in different regions of the island were evaluated. The principal observation made is the extensive use of double glazing for doors and windows.

Background: The many factors which appear to be implicated in alopecia areata (AA) include genetic and autoimmune disorders as well as emotional stress. Biotinidase deficiency, an inborn error of metabolism, causes alopecia in infants, children and adults. Subjects and methods: A fluorimetric method was used to evaluate biontinidase activity in 19 patients before and after 40 days treatment with biotin (20 mg/day p.o.). Nineteen members of the medical staff were the controls. Results: The mean biotinidase activities in our patients before treatment (3.0 ± 1.50 mmol/l/min) were statistically significantly decreased compared to those of controls (4.75 ± 0.80 mmol/l/min) as well as to those after treatment (4.40 ± 0.84 mmol/l/min). Consequently, 12 of our 19 patients showed a clinical remission of the disease after treatment, and thin white hair appeared on the frontal area of the scalp. Conclusions: An evaluation of biotinidase activity is suggested in all patients with AA and supplements of biotin are recommended.