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Sustainability and energy prices make the energy production from renewable sources necessary and photovoltaic energy is ideal on an urban scale and on isolated facilities. However, when the demand for energy is at night, as in lighting installation, the use of accumulative systems is necessary. The use of batteries can account for more than 70% of the budget of these systems and have a critical impact in the project. This problem increases when the installation’s location moves away from the equator, as the variation between the duration of days and nights increases. This implies that the system must be oversized to almost triple its generation and storage capacity to guarantee operation. This paper proposes the use of a robust and affordable electronic centralized management system that can regulate the consumption based on the energy available in the batteries. To test this system, a real case of outdoor lighting nanogrid has been used. The facility has been powered by a grouped photovoltaic battery system dimensioned for the average year solar conditions with and without consumption management. When used without regulation, in winter or cloudy days, there have been repetitive crashes of the system. On the other hand, with the use of the electronic control proposed, the shutdowns have been avoided, regulating the lighting level when necessary. Thus, more efficient and economically affordable systems can be designed which can help to spread the installation of isolated photovoltaic lighting.

Background Transplant recipients are particularly prone to the development of skin cancer, and overexposure to UV radiation during outdoor activities increases the risk of carcinogenesis. Objective The aim of this study was to analyze sun‐related behaviors and knowledge in transplant athletes, examine the frequency of sunburns, and explore associations with a history of skin cancer. Materials and methods Cross‐sectional descriptive study. Participants (n = 170) in the XXI World Transplant Games from >50 countries completed a questionnaire on sun protection habits and knowledge, type of transplant, immunosuppressive therapy, and personal history of skin cancer. Results The most common transplanted organs were the kidney (n = 79), the liver (n = 33), and the heart (n = 31). Overall, 61.3% of athletes had been doing sport for >15 years and 79.5% spent >1–2 h a day outdoors. Fifteen % of athletes had a history of skin cancer. The prevalence of sunburn in the previous year was 28.9%, higher in athletes aged <50 years (37.2%); without a primary school education (58.3%), not taking cyclosporin (32.6%), and athletes who played basketball (75%). The main sun protection measures used were sunscreen (68.9%) and sunglasses (67.3%). Use of a hat or cap was the only measure significantly associated with a reduced prevalence of sunburn. Conclusions Despite high awareness that sun exposure increases the risk of skin cancer, sunburn was common in transplant athletes. Efforts should be made to strengthen multidisciplinary sun protection education strategies and ensure periodic dermatologic follow‐up to prevent sun‐induced skin cancer in this population.

The sensitivity of the human eye varies with the different lighting conditions to which it is exposed. The cone photoreceptors perceive the color and work for illuminance conditions greater than 3.00 cd/m² (photopic vision). Below 0.01 cd/m², the rods are the cells that assume this function (scotopic vision). Both types of photoreceptors work coordinately in the interval between these values (mesopic vision). Each mechanism generates a different spectral sensibility. In this work, the emission spectra of common sources in present public lighting installations are analyzed and their normative photopic values translated to the corresponding mesopic condition, which more faithfully represents the vision mechanism of our eyes in these conditions. Based on a common street urban configuration (ME6), we generated a large set of simulations to determine the ideal light point setup configuration (luminance and light point height vs. poles distance ratio) for each case of spectrum source. Finally, we analyze the derived energy variation from each design possibility. The results obtained may contribute to improving the criterion of light source selection and adapting the required regulatory values to the human eye vision process under normalized artificial street lighting condition, reaching an average energy saving of 15% and a reduction of 8% in terms of points of light required. They also offer a statistical range of energy requirements for lighting installation that can be used to generate accurate electrical designs or estimations without the necessity of defining the exact lighting configuration, which is 77.5% lower than conventional design criteria.

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