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Resultados interactivos de una investigación llevada a cabo sobre la implementación de estrategias de rehabilitación optimizadas aplicadas al parque residencial social del sur de España en diferentes zonas climáticas (A3, A4, B4 y C3), ante escenarios climáticos futuros de cambio climático. En concreto, se ha realizado un análisis multiobjetivo en el que se optimizan, a partir de la aplicación de algoritmos genéticos, los costes de intervención de diversas soluciones de rehabilitación y el confort térmico interior en verano e invierno de las viviendas sociales, bajo escenarios futuros de calentamiento global. Todo ello se realiza mediante modelos parametrizados y validados a nivel de conjunto edificatorio, implementando información real contenida en una base de datos facilitada por la Agencia de Vivienda y Rehabilitación de Andalucía (AVRA) en los modelos de simulación dinámica de conjunto. Los resultados de esta investigación están vinculados con el proyecto: Optimización Paramétrica de Fachadas de Doble Piel en Clima Mediterráneo para la Mejora de la Eficiencia Energética ante Escenarios de cambio Climático (BIA2017-86383-R). La visualización de los resultados de esta investigación se realiza a través de ficheros .html que pueden ser accedidos fácilmente mediante cualquier navegador web. Existen tres tipos de figuras interactivas: gráficas de dispersión en 3d, gráficas de dispersión en 2d y gráficas de ejes paralelos. Se ha generado por cada zona climática analizada estos tres tipos de gráficos. En el caso de los gráficos de dispersión en 3d, el entorno web permite girar y aumentar la figura, para facilitar su visualización en el espacio. Además, colocando el cursor sobre cada punto, pueden consultarse los valores específicos de las variables de optimización (porcentaje de horas con temperaturas por encima del límite superior e inferior del confort y costes de inversión en €/m2 construido). En los gráficos en dispersión en 2d, colocando el cursor sobre cada punto, se despliega una ventana en la que pueden visualizarse los diferentes valores asociados a ese punto. En lo referente a las figuras de coordenadas paralelas, las variables de optimización pueden filtrase, seleccionando y arrastrando el cursor sobre un rango de valores buscado. Lo mismo puede realizarse con el resto de variables combinatorias. Hecho esto, la herramienta web mostrará la combinación de los paquetes de rehabilitación óptimos (variables de rehabilitación ligadas a la mejora energética de la envolvente térmica y las variables operacionales analizadas). Cada combinación, tendrá asociado un valor concreto de horas fuera del confort en verano e invierno, así como de costes de inversión. Por consiguiente, es posible realizar una comparación rápida y genérica entre diferentes actuaciones y seleccionar, de forma acorde, valorando los resultados, las medidas de rehabilitación que mejor se ajusten a los Programas e Iniciativas rehabilitadoras consideradas. v.1

The integration of residential photovoltaic (PV) systems for self-consumption is expected to unlock a variety of economic, technical and social benefits, such as the creation of local work and the reduction of the price of electricity, CO2 emissions and electrical power losses in the transmission network. In spite of all these advantages, regulatory barriers prevented the development of renewable self-consumption in Spain prior to October 2018, when a new regulation introduced the right to self-consume electrical energy without charges. This work aims to estimate the effect of residential self-consumption on the Iberian electricity market. To achieve this goal, a ceteris paribus approach was adopted, the accumulated scattered PV self-production was turned into a reduction of the aggregate demand in the market and the new clearing point was established. Based on 2017 market data, the results showed that a 1% curtailment of the annual demand due to PV self-consumption could reduce the cost of the market-traded energy by almost 2%. European Commission, Horizonte 2020 SI-1778/12/ 2018

Abstract Background and Aims Flowering is a key process in the life cycle of a plant. Climate change is shifting flowering phenologies in the Northern Hemisphere, but studies with long data series at the community level are scarce, especially those considering the consequences of phenological changes for emerging ecological interactions. In the Mediterranean region, the effects of climate change are stronger than the global average and there is an urgent need to understand how biodiversity will be affected in this area. Methods In this study, we investigated how the entire flowering phenology of a community comprising 51 perennial species from the south of the Iberian Peninsula changed from the decade of the 1980s to the 2020s. Furthermore, we have analysed the consequences of these changes for flowering order and co-flowering patterns. Key Results We have found that the flowering phenology of the community has advanced by ~20 days, which is coherent with the increasing temperatures related to climate change. Individual species have generally advanced their entire flowering phenology (start and end) and increased their flowering duration. The early flowering has resulted in a re-organization of the flowering order of the community and generated new co-flowering assemblages of species, with a slight trend towards an increase of shared flowering time among species. Conclusions The advanced flowering phenology and changes in flowering duration reported here were of unprecedented magnitude, showcasing the extreme effects of climate change on Mediterranean ecosystems. Furthermore, the effects were not similar among species, which could be attributed to differences in sensitivities of environmental cues for flowering. One consequence of these changes in flowering times is ecological mismatches, indicated by changes in the flowering order and co-flowering between decades. This new scenario might lead to new competitive or facilitative interactions and to the loss or gain of pollinators.

The objective of this paper is to analyze the factors influencing the success of real estate crowdfunding projects in Spain. This type of crowdfunding invests in real estate assets. We analyzed 60 projects published on the Housers platform, a kind of participative platform that uses the lending and equity crowdfunding modalities. These projects have involved around 36,623 investment decisions and have raised a total amount of almost 26 million euros. The empirical analysis is based on ordinary least squares and negative binomial regression. Our main findings reveal that success differs depending on the type of project; in fact, buy-to-sell projects are less successful than development loan projects. In addition, while total return has a positive impact on project success, in the case of risk level and project term, the impact is negative.

The increasing use of power electronic inverters in electrical drives is leading to the unexpected inception of partial discharges (PD) within the insulation system of electric machine stator windings. Unfortunately, the short rise and fall times of such voltages, below 100 nanoseconds in most cases, create high-magnitude conducted and radiated interferences that affect the measurements. Detecting partial discharges in these systems with inductive or electromagnetic sensors turns to be an important challenge, especially when interference and partial discharges share the same bandwidth. In this work, the authors propose a technique to detect the occurrence of PD in such systems, even when they are masked by disturbances. The proposed technique combines an analog high-pass filter stage and a digital band-pass to select a proper spectral interval. The resulting signal is converted to the base-band, where two metrics based on the peak-to-average power ratio are proposed. Experimental results obtained with the signals acquired with two antennas show that both proposed metrics exhibit a significant increase, about ten times greater, when the applied voltage exceeds the PD inception voltage. These contributions define new markers for the detection of PD events created by pulsed voltages with overlapped overshoots with promising results.

uch of the social housing stock in southern Europe is obsolete in energy terms, with users who also present very specific socio-economic profiles requiring in-depth study. Proposals for this type of housing stock of current energy retrofitting policies, based on standardized user patterns, will only contribute to increasing the ‘performance gap’ between real and estimated consumption. This study evaluates the thermal comfort conditions and energy consumption in the specific case of social housing in southern Spain, under a severe summer climate. This evaluation is based on in-situ data measurements of three housing units in use. This paper aims to test which adaptive comfort models work best in the specific conditions of the case studies and to identify the user behaviours which reduce thermal comfort. Thus, real user patterns were established and measured data were analysed. The results show that the case studies are in discomfort conditions during a high percentage of occupied hours, mainly due to the severe climate and the unsuitable use of passive measures including natural night-time ventilation and solar protection. This situation worsens with limited use of local cooling systems due to financial constraints. National regulations should define different retrofitting targets based on climatic and socio-economic conditions.

Abstract An algorithm for mapping Direct Normal Irradiance (DNI) in thermosolar power plants using a Mobile Robotic Sensor Network (RSN) is presented. The algorithm selects measurement spots and allocates the RSN accordingly to carry out the dynamic estimation of DNI. A generic thermosolar power plant with a fleet of vehicles is used as a simulated case study to assess the performance of the algorithm. The results show that the proposed method allows us to obtain a spatial estimation of the DNI that could improve the performance of the plant, and that outperforms estimations based on a single pyrheliometer.

Bajo el paraguas de la Agenda 2030 para el Desarrollo Sostenible, se han establecido diecisiete Objetivos de Desarrollo Sostenible a alcanzar en 2030. Es en este momento cuando se identifica un objetivo específico e independiente en materia de energía (Objetivo 7: «Garantizar el acceso a una energía asequible, segura, sostenible y moderna para todos»). El presente trabajo se propone abordar la tendencia mundial favorable a la descarbonización de nuestro modelo energético para alcanzar el objetivo de reducción de emisiones de gases de efecto invernadero y lograr una economía hipocarbónica, más eficiente en el uso de los recursos naturales y sostenible. Lo que sin duda forma parte de los compromisos internacionales en materia de clima y energía en consonancia con el Acuerdo de París y los Objetivos de Desarrollo Sostenible de Naciones Unidas para 2030, refrendados en la última COP26. Under the umbrella of the 2030 Agenda for Sustainable Development, seventeen Sustainable Development Goals have been established to be achieved by 2030. It is at this point that a specific, stand-alone energy goal is identified (Goal 7: “Ensure access to affordable, secure, sustainable and modern energy for all”). This work sets out to address the global trend in favour of decarbonising our energy model in order to achieve the objective of reducing greenhouse gas emissions and achieving a low-carbon, more resource-efficient and sustainable economy. This is undoubtedly part of the international commitments on climate and energy in line with the Paris Agreement and the United Nations Sustainable Development Goals for 2030, endorsed at the last COP26.