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[en] The work here described is part of the PhD thesis that is being developed with the goal of studying the hygrothermal behavior and energy performance of several dwellings in the Dry-Mediterranean Climate. In this phase, after an annual campaign of in situ experimental tests, research now focuses on the assessment and quantification of the influence of local climate conditions and thermal values of rammed earth walls on energy demands of common traditional buildings in La Mancha. To achieve it, energy simulations have been performed on two buildings, with three goals. 1) Evaluation of construction systems which include walls with a high thermal inertia in comparison with contemporary systems. 2) Study the influence of theoretical values of walls and user activity taken from nominal data in the Catalogue of Building Components (CEC), that can be found in the Technical Building Code (CTE), and compare it with the use of actual in situ data and surveys; 3) Contrast between using standard and actual climate data recorded with a private weather station placed in the same location as the studied buildings. Research like , ,  also execute energy simulations of rammed earth buildings and components but in a different climate, while other papers like , , ,  also compare in situ values with nominal data but the main material of the studied buildings is not rammed In conclusion, results show that: 1) Energy demands of spaces where the theoretical transmittance value (or U-value) has been used are 52-55% higher in winter and 9-15% higher in summer than those where the in situ value has been used. 2) The use of theoretical information against the use of actual surveys about user activity can generate 12-26% difference in energy demands. 3) On the contrary, the use of available climate data measured at nearby locations would produce lower energy demands than using values recorded in the same location as the buildings, being up to 64% lower in winter months and up to 100% lower in summer months. Future research should be performed using combined heat and moisture models (HAMT in Energy Plus), as several studies have demonstrated that there is and important relation between thermal values and water content of the material [earth.
[en] The passive design represents a solution to the energy issue in dwellings. We should highlight the existence of several elements that take belong to the field of passive design. This work aims to study de relation between the implementation of a passive design plus an active- passive design (use of renewable energy) to apply on a dwelling and the resulting energy saving. The object of study is a 100 sq. meter dwelling placed in the top floor of a seven story building in Villaverde (Madrid). To begin Design Builder software  was used, that reaches just up to energy consumption issues. In order to know the contributions about energy saving, a comparative analysis between both (original and modified) Design Builder models. 3D models in Revit and SketchUp were done in order to make a preliminary analysis. Then a passive and an active- passive designs were chosen and keeping in mind the features of the base dwelling, using Design Builder software, for a first approach and analysis of the original model and the proposed one. At the calculation phase original model’s energy requirements were observed in order to be later compared to those of the modified model...
[en] Within the sun and stars, hydrogen nuclei fuse and release tremendous amounts of energy. As soon as this process was identified just on one century ago, the idea emerged to reproduce, on earth, what nature had been doing for billions of years and thereby access a virtually inexhaustible, safe and clean source of energy to meet the needs of future generations. ITER - an acronym for the International Thermonuclear Experimental Reactor but also a Latin word meaning 'the path' - embodies that idea. In Saint-Paul-lez-Durance (in southern France), China, Europe, India, Japan, Korea, Russia and the United States have pooled their resources to build and operate the most powerful fusion reactor ever designed. Their aim: to demonstrate the feasibility of producing stellar energy
[fr]Au coeur du Soleil et des etoiles, les noyaux d'hydrogene fusionnent et liberent de formidables quantites d'energie. Sitot cette reaction identifiee il y a tout juste un siecle, une ambition s'est fait jour: reproduire, sur Terre, ce que la nature accomplit de maniere continue depuis des milliards d'annees et acceder a une source d'energie virtuellement inepuisable, sure, propre et apte a repondre aux besoins des generations futures. ITER, acronyme de International Thermonuclear Experimental Reactor, mais egalement le mot latin qui signifie 'le chemin', est l'aboutissement de cette ambition. a Saint-Paul-lez-Durance (Bouches-du-Rhone), la Chine, l'Europe, l'Inde, le Japon, la Coree, la Russie et les etats-Unis ont mis en commun leurs moyens pour construire et exploiter la plus puissante des installations de fusion jamais concue et demontrer la faisabilite de l'energie des etoiles
[en] The change to an energy model with lower carbon footprint sources, and the development of the corresponding technologies and extraction techniques has placed shale gas in the spotlight as it is a less polluting resource and it is abundant in the north of Spain. This energy model could be able to supply, to a large extent, the current energy needs of the country. However, there is a relevant lack of information on the subject regarding geological, economic, environmental and social issues. Consequently, a strong public opposition has developed, that has so far paralyzed the exploration and potential exploitation of these resources. The future changes required in the search for less polluting energy sources and the need to acquire a strategic position in the energy sector make it essential to allow both research into this resource and its exploration in Spain. Therefore, this study aims to show the current situation of natural gas in a “transitory” context towards less aggressive energies to the environment as well as to explain how shale gas is produced and how extraction should be carried out in Spain with the problems that this would entail. The study also aims to analyze the citizens’ responses and concerns regarding the development of this technology.
[es]El cambio del paradigma energético a fuentes con menor huella de carbono, así como el desarrollo de las tecnologías y técnicas para su extracción, han colocado al gas de lutita en el punto de mira como recurso menos contaminante, abundante en el norte de España, y capaz de suplir en gran medida las necesidades actuales de abastecimiento energético que requiere el país. Sin embargo, existe una importante carencia de información integrada sobre el tema, con respecto a lo geológico, lo económico, lo ambiental y lo social. Como consecuencia de todo ello, se ha desarrollado una fuerte oposición pública que ha paralizado la exploración y la posible explotación de dicho recurso. Los cambios que exige el futuro en la búsqueda de fuentes de energía menos contaminantes y la necesidad de adquirir una posición estratégica en el sector energético, hacen ineludible permitir la investigación y exploración de este recurso en España. Por ello, este trabajo pretende mostrar el panorama actual que rodea al gas natural en un contexto de “tránsito” a energías menos agresivas con el medio ambiente, cómo se realiza su extracción (gas de lutita) y, como debería llevarse a cabo en España con los problemas que ello conllevaría, así como analizar la respuesta y preocupación de la ciudadanía frente a el desarrollo de esta tecnología.
[en] As human demand for ecosystem services (ES) continues to increase, ES assessments have gradually become a popular research topic. Among ES, cultural ES (CES) are often overlooked and are difficult to measure during research because of their invisibility. However, the importance and usage of CES increase with supply and demand, which is key to linking the ecosystem with human well-being. This paper quantitatively evaluates various cultural services and generates corresponding Value Index (VI) maps; it then further explores the current dynamics of supply and demand. We selected Cuihua Mountain (CM) as the study area, and we applied the Social Values of Ecosystem Services (SolVES) model to evaluate CES and generated five specific VI maps to indicate the potential service stock (ES capacity). The actual supply (ES supply) is based on the attribute of the visibility of observation points on leisure routes, and the visitors (ES demand) to the service come from socio-economic data as a measure of the rates of access to entertainment venues. The supply and demand relationship (ES budget) solves the significant problems related to the oversupply and shortage of ES in space. The results showed that the CES supply power of CM is greater than the actual demand; thus, there is great potential for future development. This study also provided a reference and guidance for environmental decision-making and development in other regions.
[en] Reducing energy consumption in the residential sector is a major challenge in the context of the energy transition. Indeed, the environmental pressure linked to the production of fossil fuels, which are heavy emitters of greenhouse gases, encourages us to be energy sober. In short: controlling household energy demand. The thesis examines the development of a 'green' housing stock, and focuses on the Energy Performance Diagnosis (DPE) which synthesizes information on the energy performance of a dwelling
[fr]Reduire les consommations energetiques du secteur residentiel est un enjeu majeur dans le cadre de la transition energetique. En effet, la pression environnementale liee a la production d'energies fossiles, lourdement emettrices de gaz a effets de serre, nous incite a la sobriete energetique. En somme: maitriser la demande d'energie des menages. La these interroge le developpement d'un parc immobilier 'vert', et porte son attention sur le Diagnostic de Performance Energetique (DPE) qui synthetise les informations sur la performance energetique d'un logement
[en] As much wind power is connected to the power system, the accommodation of the wind power in the power grids becomes a huge challenge to the operation model of China’s power system. Releasing and improving the flexibility of the power system will be necessary and important to enable the accommodation of power generated with renewable energy sources, which is connected to the power grids on a large scale and accounts for a high proportion. The paper, with North Hebei as an example, discusses the relationship between the demand for the flexibility of thermal power units and the accommodation of wind power. This paper further analyzes the demand for peak load regulation in North Hebei at both the present and the future as well as the characteristics of power sources in the power grids of North Hebei and the technical potential of power generation. It also compares the quantity of curtailed power before and after the flexibility-oriented transformation of thermal power units in North Hebei and calculates the minimum technical output of thermal power under different levels of accommodation of wind power. The research shows that the peak load regulating resources in the power grids of North Hebei boast huge potential, but in the long term, to achieve the objective of a 10% curtailment rate of power generated with renewable energy sources, the minimum technical output of condensing units must be lower than the internationally advanced level of 25%. So, it is difficult to fulfill the said objective solely relying on the strengthened transformation of generating units. To reach the level of 5% curtailment rate of power generated with renewable energy sources, the minimum technical output must achieve breakthrough improvement, which requires continuous technological innovation and power flexibility in close coordination.
[en] Growing household energy demand, particularly in developing countries starting from a low base of consumption, is an important driver of current and future greenhouse gas emissions. Yet, our understanding of transitioning residential energy demand in developing country contexts is limited. This paper discusses changing energy service demands in urban low-income households in India, an emerging economy where the largest future growth in energy demand globally is projected to occur, and where 12 million new low-income homes for the urban poor are to be built by the government between 2015 and 2022. Based on mixed quantitative and qualitative methods comprising of surveys, interviews and focus group discussions, we analyze two inter-related questions: how does the demand for energy services change as the ability of low-income households to consume increases; and how do energy related behaviors influence household electricity consumption? We analyze the data collected to rank households according to their ability to consume and to identify the types of, and progression in, energy services acquired. The appliances and associated services pursued are lights, fans, televisions, and refrigerators, with varied energy efficiencies. Analogously, we quantify the influence of behavior in determining electricity consumption, and show that the inclusion of socio-demographic and behavioral factors explain a significant proportion (51%) of the variance in household electricity consumption, along with the role of material factors such as building physical characteristics and appliance stocks. We complement the statistical analysis with qualitative fieldwork and discuss changing energy related behaviors as the ability of households to consume increases. We conclude with recommendations for climate actions that are compatible with development in the growing low-income housing stock. (letter)
[en] Since the “China Western Development” plan was initiated in 2000, the Sichuan–Chongqing region has experienced rapid economic growth, especially in the energy segment. However, energy shortage and environmental degradation currently pose a significant hurdle for sustainable development in this region. In the existing literature on factors driving the energy demand, the effect of technological progress on energy demand is discussed as a whole, but few papers have investigated the effect of technological progress from the perspective of its components. Additionally, existing studies have neglected the temporal and spatial aspect of energy demand, thereby generating biased and unreasonable results. Correspondingly, in the current study, the factors driving the per capita energy demand in the Sichuan–Chongqing region over the 2005–2016 period were, to the best of our knowledge, explored for the first time by employing the data envelopment analysis–Malmquist method and spatial dynamic panel model concurrently. The empirical results suggest that an improvement in total factor productivity (TFP) plays a positive but insignificant role in decreasing energy demand. Additionally, there is clear evidence that the effect of TFP on energy demand primarily emerges through spatial spillover effects and their components.