Results 1 - 10 of 248
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[en] The impacts are getting closer, and we all know the consequences. There is probably no one in the energy industry who is not familiar with the novel "BLACKOUT-Morgen ist es zu spät" (It's Too Late in the Morning BLACKOUT), which was published on 17.6.2013.
[de]Die Einschläge kommen näher und wir kennen alle die Folgen. Es dürfte (wahrscheinlich) niemand in der Energiebranche geben, der den am 17.6.2013 erschienenen Roman "BLACKOUT-Morgen ist es zu spät" nicht kennt.
[en] Highlights: • Reviews how the concept of energy service has been used to analyse energy demand. • Argues that common uses are too static and neglect the core meaning of service as useful work. • A concept of meta-services is proposed as a nexus of expectation, provision and experience. • Highlights: role of multiple stakeholders in shaping energy-service demand. • Discusses policy implications for servicizing and demand reduction. - Abstract: The idea that energy is not consumed for its own sake but for the services that it provides has become axiomatic. However, the implications are not worked through into energy policy nor into most analyses of energy demand. Instead, energy service demand is usually isolated from its dynamic and varied socio-cultural basis, rendering it inappropriately static and neglecting the core quality of usefulness that definitions of ‘energy service’ share. To address these limitations, this paper revisits and extends a sociological conceptualisation of services, referred to here as meta-services. These are composite and cross-cutting formations of convention, expectation and experience and the means of achieving them. Meta-services are more-than-energy services and are shaped not only through energy consumption, provision and governance but also by a range of other non-energy providers and organisations. This calls for demand reduction policies to engage wider coalitions of service ‘stakeholders’. In addition, because energy-services co-constitute meta-services, aspirations to deliver the same levels of service but more efficiently risk entrenching, rather than reducing, levels of service demand. Implications for service-based business models (servicizing) and policies are discussed.
[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 challenge for the nuclear community is to assure that nuclear power remains a viable option in meeting the energy requirements of the next century. It could be a major provider of electricity for base load as well as for urban transport in megacities. It can play a role in non-electric applications in district heating, process industries, maritime transport. (author)
[en] Highlights: • Existing demand-side responses are inadequate to prevent dangerous climate change. • Non-energy policy objectives and processes matter for energy demand. • Demand reduction objectives should be ‘mainstreamed’ into non-energy policy. • More research is needed to uncover impacts of non-energy policies on energy demand. - Abstract: This article makes the case for a new and ambitious research and governance agenda for energy demand reduction. It argues that existing ‘demand-side’ approaches focused on promoting technological efficiency and informed individual consumption are unlikely to be adequate to achieving future carbon emissions reduction goals; it points out that very little attention has so far been paid to the impacts of non-energy policies on energy demand; and it submits that a much fuller integration of energy demand questions into policy is required. It advances a general framework, supported by illustrative examples, for understanding the impacts of ‘non-energy’ policies on energy demand. It reflects on why these connections have been so little explored and addressed within energy research and policy. And it argues that, for all their current ‘invisibility’, there is nonetheless scope for increasing the visibility of, and in effect ‘mainstreaming’, energy demand reduction objectives within other policy areas. Researchers and policymakers, we contend, need to develop better understandings of how energy demand might be made governable, and how non-energy policies might be revised, alone and in combination, to help steer long-term changes in energy demand.
[en] Highlights: • Biofuels are produced by Fischer-Tropsch synthesis using the syngas obtained by supercritical reforming. • A plant capacity of 60 t/h and a feeding concentration of 25 wt% were established as the base-case. • The aim of the energy self-sufficient process was to maximize the biofuel production and electrical power. • The break-even prices were 1.20, 0.93 and 0.26 €/kg for gasoline, diesel and jet-fuel, respectively. • The process competitiveness is promising with respect to that of fossil fuels of crude oil. - Abstract: High energy demand along with large capital costs have been the main drawbacks of Fischer-Tropsch plants, which may call into question the economic viability of the Fischer-Tropsch process. The second issue is the focus of this paper, which presents a techno-economic assessment of biofuels production by a low-temperature Fischer-Tropsch synthesis with electricity as a co-product from supercritical water reforming of the bio-oil aqueous phase. A plant size of 60 t/h was considered and a heat-integrated process was designed to be energy self-sufficient, which includes syngas production and upgrading, as well as liquid fuels production by Fischer-Tropsch synthesis and refining. The simulation and optimization was performed with the aid of Aspen Plus, and some case-studies were performed. Using a feeding concentration of 25 wt%, 2.74 t/h biofuels and 5.72 MWe were obtained. In this case, by performing a discounted cash flow analysis, with 10% rate of return and 100% equity financing, the minimum selling prices for the refined FT-gasoline, FT-diesel and FT-jet fuel were 1.20, 0.93 and 0.26 €/kg (0.84, 0.75 and 0.20 €/L), respectively, which are competitive prices with respect to the market values of the equivalent fossil fuels. Likewise, the decrease in the selling prices as the plant capacity increases was also analyzed.
[en] The development of renewable energies is growing over the last decade to face environmental issues due to the world fossil fuel consumption increase. These energies are highly involved in houses and commercial buildings and numerous systems have been proposed to meet their energy demand. Therefore, improving both efficiency and use of systems, i.e. improving energy management, appears essential to limit the ecological footprint of humanity on the planet. However, system integration yields a very complex problem to be solved due to the large number of units and theirs technology, size, working conditions and interconnections. This situation highlights the lack of systematic analysis for comparing integrated system performance and for correctly point-ing out their potential. As a result, the objective of this thesis is to develop and to present such a method, in other words the structural optimization of energy systems. It will be helpful to choose the optimal equipment by identifying all the possibilities of system arrangements and for comparing their performance. Combinations have then been subjected to environmental (climate), structural (available area) and economical constrains while assessment criteria have considered both energy, economic and ecological aspects. For that reason, as well as energy and economic analyses, the exergy concept has also been applied to the equipment. Nevertheless, the high degree of complexity of integrated systems and the tedious numerical calculations make the resolution by using standard software very difficult. It is clear that the whole optimization project would be considerable and the aim is to develop models and optimization tools. First of all, an exhaustive review of energy equipment including photovoltaic panels, solar collectors, heat pumps and thermal energy storage systems, has been performed. Afterwards, energy and exergy models have been developed and tested for two specific energy scenarios: a) a solar assisted heat pump using ice and warm water storages and b) an ambient air heat pump associated to photovoltaic panels. A superstructure has then been constructed to account for every system combination possibility. The different energy paths have been illustrated while irreversibility along every path is identified. Thus, it allows the system operation to be clearly understood. Besides, an exergy diagram has been developed and permits energy and exergy assessment of system and system arrangements to be not only identified but also quantified and separated depending on their (renewable or non-renewable) source. Finally, dimensions and operation variables have been optimized according to exergy and economic criteria for the aforementioned scenarios; the potential of each energy option has been estimated and yield a better energy management to be reached. (author)
[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] 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] Grid connected solar system is an emerging technology to harvest solar incident radiation for production of electricity which can be fed to the grid directly. As part of the energy conservation activities as well as considering the importance the Government of India has given to harness Solar Energy, IGCAR has initiated projects in this line. To start with, a pilot plant of 30 kWp grid connected solar plant is installed and commissioned on 14th August 2015. On an average, this system, produces 120 to 150 units of electricity per day. On days with good solar insolation the production clocked 175 units. This is the largest solar system installed at Kalpakkam so far. All the operations are automatic and no manual intervention is envisaged for normal operation. It is not provided with any battery backup as the electricity generated is transferred to the gird on real time basis and no storage is necessary. This arrangement will ensure better efficiency at a lesser capital and maintenance cost