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AbstractDecarbonising the energy system requires high shares of variable renewable generation and sector coupling like power to heat. In addition to heat supply, heat pumps can be used in future energy systems to provide flexibility to the electricity system by using the thermal storage potential of the building stock and buffer tanks to shift electricity demand to hours of high renewable electricity production. Bridging the gap between two methodological approaches, we coupled a detailed building technology operation model and the open-source energy system model Balmorel to evaluate the flexibility potential that decentral heat pumps can provide to the electricity system. Austria in the year 2030 serves as an example of a 100% renewable-based electricity system (at an annual national balance). Results show that system benefits from heat pump flexibility are relatively limited in extent and concentrated on short-term flexibility. Flexible heat pumps reduce system cost, CO2 emissions, and photovoltaics and wind curtailment in all scenarios. The amount of electricity shifted in the assessed standard flexibility scenario is 194 GWhel and accounts for about 20% of the available flexible heat pump electricity demand. A comparison of different modelling approaches and a deterministic sensitivity analysis of key input parameters complement the modelling. The most important input parameters impacting heat pump flexibility are the flexible capacity (determined by installed capacity and share of control), shifting time limitations, and cost assumptions for the flexibility provided. Heat pump flexibility contributes more to increasing low residual loads (up to 22% in the assessed scenarios) than decreasing residual load peaks. Wind power integration benefits more from heat pump flexibility than photovoltaics because of the temporal correlation between heat demand and wind generation.

This report reflects upon the concept of social innovation and the way it is used in the energy sector. It does so by bringing together theoretical investigations and empirical knowledge. We aim to clarify the concept of social innovation in the energy sector by reviewing the literature and reflecting over a number of social innovation projects in Europe. The analysis of the projects against various contextual factors and their goals reveals the significant potential of social innovation on accelerating the energy transition while tackling societal problems. Energy production, energy efficiency and energy literacy are the main domains to which socially innovative activities contribute the most. High competences of project leadership and management observed though projects are often small in scale and context-dependent. This indicates that successful socially innovative energy initiatives require advanced bottom-up governance structures even if that may imply limitations for scaling up. This setting may complicate top-down support as legal, financial or even cultural policy-making must be tailor-made and reinvent or adjust continuously. Nevertheless, social innovative activities are expected to further proliferate the following years and move towards a sound environmental, cultural, political, economic and social direction, as knowledge creation and diffusion of technological and governance innovations accompanied with policy support are on the rise. JRC.C.7-Knowledge for the Energy Union

The energy considered as waste heat in industrial furnaces owing to inefficiencies represents a substantial opportunity for recovery by means of thermal energy storage (TES) implementation. Although conventional systems based on sensible heat are used extensively, these systems involve technical limitations. Latent heat storage based on phase change materials (PCMs) results in a promising alternative for storing and recovering waste heat. Within this scope, the proposed PCM-TES allows for demonstrating its implementation feasibility in energy-intensive industries at high temperature range. The stored energy is meant to preheat the air temperature entering the furnace by using a PCM whose melting point is 885 °C. In this sense, a heat transfer model simulation is established to determine an appropriate design based on mass and energy conservation equations. The thermal performance is analysed for the melting and solidification processes, the phase transition and its influence on heat transference. Moreover, the temperature profile is illustrated for the PCM and combustion air stream. The obtained results prove the achievability of very high temperature levels (from 700 to 865 °C) in the combustion air preheating in a ceramic furnace; so corroborating an energy and environmental efficiency enhancement, compared to the initial condition presenting an air outlet at 650 °C.

With the aim to fully exploit the by-products obtained after the industrial extraction of starch from sweet potatoes, a cascading approach was developed to extract high-value molecules, such as proteins and pectins, and to valorize the solid fraction, rich in starch and fibrous components. This fraction was used to prepare new biocomposites designed for food packaging applications. The sweet potato residue was added to poly(3-hydroxybutyrate-co-3-hydroxyvalerate) in various amounts up to 40 wt % by melt mixing, without any previous treatment. The composites are semicrystalline materials, characterized by thermal stability up to 260 °C. For the composites containing up to 10 wt % of residue, the tensile strength remains over 30 MPa and the strain stays over 3.2%. A homogeneous dispersion of the sweet potato waste into the bio-polymeric matrix was achieved but, despite the presence of hydrogen bond interactions between the components, a poor interfacial adhesion was detected. Considering the significant percentage of sweet potato waste used, the biocomposites obtained show a low economic and environmental impact, resulting in an interesting bio-alternative to the materials commonly used in the packaging industry. Thus, according to the principles of a circular economy, the preparation of the biocomposites closes the loop of the complete valorization of sweet potato products and by-products.

AbstractEuropean climate is associated with variability and changes in the mid-latitude atmospheric circulation. In this study, we aim to investigate potential future change in circulation over Europe by using the EURO-CORDEX regional climate projections at 0.11° grid mesh. In particular, we analyze future change in 500-hPa geopotential height (Gph), 500-hPa wind speed and mean sea level pressure (MSLP) addressing different warming levels of 1 °C, 2 °C and 3 °C, respectively. Simple scaling with the global mean temperature change is applied to the regional climate projections for monthly mean 500-hPa Gph and 500-hPa wind speed. Results from the ensemble mean of individual models show a robust increase in 500-hPa Gph and MSLP in winter over Mediterranean and Central Europe, indicating an intensification of anticyclonic circulation. This circulation change emerges robustly in most simulations within the coming decade. There are also enhanced westerlies which transport warm and moist air to the Mediterranean and Central Europe in winter and spring. It is also clear that, models showing different responses to circulation depend very much on the global climate model ensemble member in which they are nested. For all seasons, particularly autumn, the ensemble mean is much more correlated with the end of the century than most of the individual models. In general, the emergence of a scaled pattern appears rather quickly.

Dans les latitudes tempérées élevées, les ongulés donnent généralement naissance dans une fenêtre temporelle étroite lorsque les conditions sont optimales pour la survie de la progéniture au printemps ou au début de l'été, et utilisent une photopériode changeante pour les conceptions temporelles afin d'anticiper ces conditions. Cependant, dans les basses latitudes tropicales, la variation de la durée du jour est minime et la variation des précipitations rend le cycle saisonnier moins prévisible. Néanmoins, plusieurs espèces d'ongulés conservent des pics de naissance étroits dans de telles conditions, tandis que d'autres montrent que les naissances se propagent assez largement tout au long de l'année. Nous avons étudié comment la variation des précipitations d'une année à l'autre et d'une année à l'autre a influencé le moment de la reproduction de quatre espèces d'ongulés montrant ces modèles contrastés dans la région de Masai Mara au Kenya. Les quatre espèces présentaient des pics de naissance au cours de la période optimale putative au début de la saison humide. Pour le hartebeest et l'impala, le pic de naissance est diffus et la progéniture naît tout au long de l'année. En revanche, le topi et le phacochère ont montré une concentration saisonnière étroite de naissances, avec des conceptions supprimées une fois que les précipitations mensuelles sont tombées en dessous d'un seuil. Les fortes précipitations de la saison précédente et les fortes pluies précoces de l'année en cours ont amélioré la survie au stade juvénile de toutes les espèces, à l'exception de l'impala. Nos résultats révèlent comment la variation des précipitations affectant la croissance des graminées et donc la nutrition des herbivores peut régir la phénologie reproductive des ongulés dans les latitudes tropicales où la variation de la longueur du jour est minime. Le mécanisme sous-jacent semble être la suppression des conceptions une fois que les gains nutritionnels deviennent insuffisants. En réagissant de manière proximale à la variation des précipitations au cours de l'année, les ongulés de la savane tropicale sont moins susceptibles d'être affectés négativement par les conséquences du réchauffement climatique sur la phénologie de la végétation que les ongulés du Nord montrant un contrôle photopériodique plus rigide sur le moment de la reproduction. En latitudes templadas altas, los ungulados generalmente dan a luz dentro de una ventana de tiempo estrecha cuando las condiciones son óptimas para la supervivencia de la descendencia en primavera o principios del verano, y utilizan conceptos cambiantes de fotoperíodo a tiempo para anticipar estas condiciones. Sin embargo, en latitudes tropicales bajas, la variación de la duración del día es mínima, y la variación de las precipitaciones hace que el ciclo estacional sea menos predecible. Sin embargo, varias especies de ungulados conservan picos de nacimiento estrechos en tales condiciones, mientras que otras muestran nacimientos muy extendidos a lo largo del año. Investigamos cómo la variación interanual de las precipitaciones influyó en el tiempo reproductivo de cuatro especies de ungulados que muestran estos patrones contrastantes en la región de Masai Mara en Kenia. Las cuatro especies exhibieron picos de nacimiento durante el periodo óptimo putativo en la estación húmeda temprana. Para hartebeest e impala, el pico de nacimiento era difuso y las crías nacían durante todo el año. Por el contrario, topi y jabalí mostraron una estrecha concentración estacional de nacimientos, con concepciones suprimidas una vez que las precipitaciones mensuales cayeron por debajo de un nivel umbral. Las altas precipitaciones en la temporada anterior y las altas lluvias tempranas en el año en curso mejoraron la supervivencia en la etapa juvenil para todas las especies, excepto los impalas. Nuestros hallazgos revelan cómo la variación de la precipitación que afecta el crecimiento de la hierba y, por lo tanto, la nutrición de los herbívoros, puede gobernar la fenología reproductiva de los ungulados en latitudes tropicales donde la variación de la duración del día es mínima. El mecanismo subyacente parece ser la supresión de las concepciones una vez que las ganancias nutricionales se vuelven insuficientes. Al responder proximalmente a la variación de las precipitaciones dentro del año, es menos probable que los ungulados de la sabana tropical se vean afectados negativamente por las consecuencias del calentamiento global para la fenología de la vegetación que los ungulados del norte que muestran un control fotoperiódico más rígido sobre el tiempo reproductivo. In high temperate latitudes, ungulates generally give birth within a narrow time window when conditions are optimal for offspring survival in spring or early summer, and use changing photoperiod to time conceptions so as to anticipate these conditions. However, in low tropical latitudes day length variation is minimal, and rainfall variation makes the seasonal cycle less predictable. Nevertheless, several ungulate species retain narrow birth peaks under such conditions, while others show births spread quite widely through the year. We investigated how within-year and between-year variation in rainfall influenced the reproductive timing of four ungulate species showing these contrasting patterns in the Masai Mara region of Kenya. All four species exhibited birth peaks during the putative optimal period in the early wet season. For hartebeest and impala, the birth peak was diffuse and offspring were born throughout the year. In contrast, topi and warthog showed a narrow seasonal concentration of births, with conceptions suppressed once monthly rainfall fell below a threshold level. High rainfall in the previous season and high early rains in the current year enhanced survival into the juvenile stage for all the species except impala. Our findings reveal how rainfall variation affecting grass growth and hence herbivore nutrition can govern the reproductive phenology of ungulates in tropical latitudes where day length variation is minimal. The underlying mechanism seems to be the suppression of conceptions once nutritional gains become insufficient. Through responding proximally to within-year variation in rainfall, tropical savanna ungulates are less likely to be affected adversely by the consequences of global warming for vegetation phenology than northern ungulates showing more rigid photoperiodic control over reproductive timing. في خطوط العرض المعتدلة العالية، تلد ذوات الحوافر عمومًا في غضون فترة زمنية ضيقة عندما تكون الظروف مثالية لبقاء النسل في الربيع أو أوائل الصيف، وتستخدم تغيير الفترة الضوئية إلى مفاهيم زمنية لتوقع هذه الظروف. ومع ذلك، في خطوط العرض الاستوائية المنخفضة، يكون تباين طول اليوم ضئيلًا، ويجعل تباين هطول الأمطار الدورة الموسمية أقل قابلية للتنبؤ. ومع ذلك، فإن العديد من الأنواع ذوات الحوافر تحتفظ بقمم ولادة ضيقة في ظل هذه الظروف، في حين أن البعض الآخر يظهر أن الولادات تنتشر على نطاق واسع خلال العام. لقد حققنا في كيفية تأثير التباين في هطول الأمطار خلال العام وبين الأعوام على التوقيت التكاثري لأربعة أنواع من ذوات الحوافر تظهر هذه الأنماط المتناقضة في منطقة ماساي مارا في كينيا. أظهرت جميع الأنواع الأربعة قمم ولادة خلال الفترة المثلى المفترضة في موسم الأمطار المبكر. بالنسبة لحيوان النحل والامبالا، كانت ذروة الولادة منتشرة وولدت ذرية على مدار العام. على النقيض من ذلك، أظهر التوبي والخنزير الحربي تركيزًا موسميًا ضيقًا للولادات، مع قمع المفاهيم بمجرد انخفاض هطول الأمطار الشهري إلى ما دون مستوى العتبة. عزز ارتفاع هطول الأمطار في الموسم السابق وارتفاع الأمطار المبكرة في العام الحالي البقاء على قيد الحياة في مرحلة الشباب لجميع الأنواع باستثناء الإمبالا. تكشف النتائج التي توصلنا إليها كيف أن تباين هطول الأمطار الذي يؤثر على نمو العشب وبالتالي تغذية الحيوانات العاشبة يمكن أن يحكم الفينولوجيا الإنجابية لذوات الحوافر في خطوط العرض الاستوائية حيث يكون تباين طول اليوم ضئيلًا. يبدو أن الآلية الأساسية هي قمع المفاهيم بمجرد أن تصبح المكاسب الغذائية غير كافية. من خلال الاستجابة القريبة من التباين في هطول الأمطار خلال العام، فإن ذوات الحوافر في السافانا الاستوائية أقل عرضة للتأثر سلبًا بعواقب الاحترار العالمي على فينولوجيا الغطاء النباتي من ذوات الحوافر الشمالية التي تظهر تحكمًا دوريًا ضوئيًا أكثر صرامة في توقيت التكاثر.