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[en] This article outlines that Germany must redouble its efforts to reach its objectives of reduction of greenhouse gas emissions defined for 2030, and that renewable energies are already representing more than the half of the German energy mix whereas its energy transition is controversial. Thus, the author evokes the huge investments made since 2000, the ambitious program of development of renewable energies, that this development is said to be too slow regarding some aspects. While evoking the example of a village which is considered as a model as far as successful energy transition is concerned, current developments are mentioned regarding infrastructures, notably the important issue of reinforcement of the high voltage network, and ecological and economic issues. The last part more particularly addresses the strategic importance of a local photovoltaic panel production, and actions and supports to phase out coal mining and use
[en] In recent years, annual electricity consumption in France amounted to around 470 TWh, 90% being decarbonized; at the same time, oil and natural gas consumption has been around 900 TWh and 450 TWh respectively. At present, electricity accounts for only a quarter of energy consumption. Energy savings alone will not be enough to move away from oil and natural gas: as equally anticipated for Germany and Great Britain, French reliance on electricity will have to increase significantly to replace oil and gas consumption. Various recent projections underestimate this growth. However, erroneous assumptions would affect the security of our energy supply and the daily life of the French people; the impacts on the cost of electricity and energy in general, and on the competitiveness of our economy would be considerable. In this position paper, the National Academy of Technologies of France (NATF) proposes a reasonable assessment of electricity demand in 2050. It points out that the European electricity system will be more vulnerable in coming years. It proposes some principles for the choice of economic data to be used in optimisation models. On the basis of these elements, it highlights some key points for managing change in the electricity system.
[fr]La consommation annuelle d'electricite en France a ete d'environ 470 TWh, decarbonee a plus de 90%; dans le meme temps, les consommations de petrole et de gaz naturel ont ete respectivement d'environ 900 TWh et 450 TWh. L'electricite ne represente aujourd'hui que le quart de la consommation d'energie. Les seules economies d'energie ne suffiront pas a sortir du petrole et du gaz naturel: comme le prevoient egalement l'Allemagne et la Grande-Bretagne, le recours a l'electricite en France devra croitre significativement pour se substituer aux consommations de petrole et de gaz. Diverses estimations recentes sous-estiment cette croissance. Or des anticipations erronees affecteraient la securite de notre approvisionnement energetique et la vie quotidienne des francais; les impacts sur le cout de l'electricite et des energies en general, et sur la competitivite de notre economie seraient majeurs. Dans cet avis, l'Academie des technologies propose une evaluation raisonnable de la demande d'electricite en 2050. Elle rappelle que le systeme electrique europeen sera plus fragile dans les prochaines annees. Elle propose quelques principes pour le choix des donnees economiques a retenir dans les optimisations. A partir de ces elements, elle souligne quelques points clefs de la conduite du changement du systeme electrique.
[en] While France and a growing number of countries around the world have been setting ambitious goals for reaching net-zero emissions, variable renewables like wind and solar energy are set to become the main building blocks in power systems worldwide as countries seek to decarbonise their economies. In a new joint analysis commissioned by the French Ministry for the Ecological Transition, the IEA (International Energy Agency) and RTE (Reseau de Transport d'Electricite) describe four essential areas that policy makers must address when wind and solar PV start to dominate electricity generation. The new report, Conditions and requirements for the technical feasibility of a power system with a high share of renewables in France towards 2050, outlines four groups of strict conditions that need to be met to integrate very high shares of renewables in a technically secure way in a large and meshed power system such as that of France. - Power system strength: Even if they still need to be proven at large scale, there is a general scientific consensus that technological solutions to maintain system strength - and therefore stability - without conventional generation exist in several cases. Specific difficulties are expected in the case of a system with a significant share of distributed solar PV. Further assessment of the impacts of distributed PV on the power distribution network and their implications for electricity security is needed. - System adequacy: This is the ability of a power system to cope with a given load at all times. It can be ensured even in a system mainly based on variable renewables as long as substantial sources of flexibility are available, including demand-response, large-scale storage, peak generation units and well-developed transmission networks and interconnections. The maturity, availability and cost of different flexibility mixes need to be evaluated in further analysis. - Operational reserves: The sizing of these reserves and the regulatory framework for balancing responsibilities and procurement would need to be substantially revised in a large power system as such that of France. Moreover, forecasting methods for variable renewables would need to be continually improved. - Grid development: Substantial efforts would be necessary beyond 2030 at both transmission and distribution levels. This requires strong proactive steps and public engagement in long-term planning in order to assess costs and work with citizens on social acceptance of new infrastructure. These efforts can nonetheless be partly integrated into the renewal of ageing network assets. The joint study marks an important step and is part of a larger work program aimed at developing and comparing scenarios for the long-term transformation of the electricity system to achieve carbon neutrality by 2050. On 27 January 2021, RTE will open a public consultation assessing the framework and assumptions of these future scenarios, and will present the conclusions of this consultation in the Fall 2021.
[en] The fishing industry of the China is the largest in world which is usually believed to be facing overexploitation risk. In this condition, it becomes necessary to estimate stock status of fishery resources particularly having commercial importance. Thus, this study is the first time attempt to know whether Spanish mackerel, a major landed fishery resource in Shandong, China, is experiencing overexploitation or not by estimating its stock status. For this purpose, long data series, 2006-2016, comprised of catch and effort figures was statistically analyzed to know maximum sustainable yield (MSY) of this resource and its ongoing regime. In total, three surplus production models (SPMs) were used in this study, viz., Fox (FM), Schaefer (SM) and Pella-Tomlinson (PTM) with the help of two famous fishery statistical routines, viz., catch and effort data analysis (CEDA) and a stock production model incorporating covariates (ASPIC). For initial proportion (IP) 1, CEDA estimated MSY in a range between 41000-50000 t, whereas, ASPIC calculations remained between 44000-52000 t. Furthermore, results also showed that fishing mortality (F) is increasing while biomass (B) is swiftly decreasing. Based on the results it can be concluded that Spanish mackerel is facing the risk of overexploitation. Thus, it is recommended to make such policies which can conserve this fishery resource for future. (author)
[en] In accordance with French legislation, each year RTE drafts and publishes the 'Generation Adequacy Report' concerning the supply-demand balance of electricity. As a diagnostic reference for security of supply and of the electric network, the report is a key corporate exercise which is used to shed light on the medium to long term forecasts for security of supply, and therefore to develop national energy policies. This 2021 report presents: 1 - The next ten years: transformation of the energy mix to make it a major vector of global CO2 emissions abatement in France; 2 - A security of supply under watchful eye for the next 3 winters; 3 - 2024-2026: a pivotal deadline to materialize the decarbonization trend and to reinforce the security of supplies; 4 - A largely transformed electric system by 2030 allowing the start-up of a deep decarbonization of economy; 5 - A reinforced analysis of the security of supplies and of its reinforcement means.
[en] Whereas the French law related to energy transition for a green growth defined the objective of energy self-sufficiency in overseas territories by 2030 (i.e. a higher objective than for the metropolitan mainland), this report proposes a synthesis and comparative analysis of studies performed for 6 territories (Mayotte, Reunion, Guadeloupe, Martinique, and Guyana by 2030, and Corsica by 2050). The main lessons learned from these studies are highlighted: possibility of a 100 pc renewable electricity mix, issue of energy management, high reduction of the importance of Diesel plants, significant share of varying wind and photovoltaic energies, decrease of the costs of the produced energy, electricity systems appeared to be steady. It discusses the context and conditions to reach the defined objectives. It presents the methodology and main hypotheses of the performed studies: elaboration of a data set, optimisation of trajectories of evolution of the electricity mix for 5 scenarios, ex-post economic analysis, modelling of the 5 scenarios for each territory. Results are globally presented (an expected decrease of global costs of electricity, an electricity system which could remain steady in front of significant incidents), and the limitations and perspectives of the study are discussed. Results are then presented for the six different territories (data in 2017 and 2030, renewable potentials, mix analysis for each scenario, economic analysis of scenarios, focus on a specific scenario).
[fr]La loi relative a la transition energetique pour la croissance verte (LTECV) a fixe comme objectif de parvenir a l'autonomie energetique dans les departements et regions d'outre-mer (DROM) a l'horizon 2030. La Collectivite Territoriale de Corse vise ce meme objectif pour 2050. L'ADEME a souhaite mener une etude pour evaluer les implications techniques, organisationnelles et economiques qu'aurait un mix electrique tres fo tement renouvelable dans ces territoires, pour la majorite insulaires (Mayotte, La Reunion, la Guadeloupe, la Martinique, la Guyane et la Corse). Le vecteur electrique, permettant une production locale basee sur les energies renouvelables, et adapte a de multiples usages en substitution a des energies fossiles importees, pourrait jouer un role preponderant pour atteindre cet objectif ambitieux d'autonomie energetique. A l'heure de la revision des Programmations Pluriannuelles de l'Energie des ZNI (PPE), cette etude se veut un outil d'aide pour les instances decisionnelles afin de nourrir la reflexion des parties prenantes et ouvrir le champ des possibles.
[en] Fuel pool cooling is an essential task in the scope of nuclear power applications. During the first years of commercial nuclear power implementation robust fuel pool cooling systems have been developed and used for several decades. Two decades ago the development of a new cooling technology/concept was initiated to ensure prevention of accidents, including fuel damage. The so-called advanced cooling technology offers a modular design system which enables tailor-made robust and cost efficient cooling solutions. However, all the advanced cooling systems feature an indispensable and distinctive fall back option of a passive heat removal in case of a station blackout as most important feature. In contradiction to conventional cooling systems the advanced cooling solutions use immersed heat exchangers to establish an additional safety barrier inside the heat removal chain. This results in the necessity of a free convective heat transfer on pool water side. This in turn requires a special design approach and methodology. Because of the huge nominal heat load and the size of the heat removal systems itself full size test are under economical aspects nearly impossible. In this paper a purpose-built simulation and design methodology is presented, which has been developed and proved in the scope of several first-of-a-kind projects during the last years.
[en] The government of India is promoting the electric vehicle industry to reduce the import dependence on crude oil and natural gas and to achieve ecological benefits. Electric vehicle projects are forging ahead due to the proactive policies of the government. The lithium-ion battery is an essential component of an electric vehicle. The lithium-ion battery is also used in the energy storage device and the communication sector. Presently, lithium-ion battery cells are not produced in India. Indian demand for lithium-ion cells are entirely met by import. However, battery packs are assembled in India with imported battery cells by a few units. (author)
[en] Quinone-based macrocyclic compounds have been proposed as promising electrode materials for rechargeable lithium-ion batteries (LIBs). To improve the electrochemical performance, in this paper, two heteroatom-bridged pillarquinones (namely, oxa- and thia-pillarquinones) are presented as active cathode materials for LIBs. The geometry structures, electronic structural properties, and electrochemical properties of these new species are calculated by Density Functional Theory (DFT) at the M06-2X/6-31G(d,p) level of theory. Two heteroatom-bridged pillarquinones possess higher theoretical specific capacity (659 mA h g-1 and 582 mA h g-1 for oxa- and thia- pillarquinones, respectively) than that of parental pillarquinone (446 mA h g-1). The electrochemical performances of oxa- and thia-pil-larquinones are predicted theoretically to be superior to those of pillarquinone as cathode material for LIBs. Compared with oxa-pillarquinone, thia-pillarquinone is predicted to be slightly more suitable as cathode electrode material. These results may provide fresh ideas and guidelines for enhancing the performance of quinones organic electrode materials for LIBs. (author)
[en] The cyanobacterium, Leptolyngbya sp. and green microalga, Chlorella sorokiniana as biofertilizers, play an important role in agriculture development. Due to a lack of information concerning microalgae as biofertilizers in crop production, the present research aimed to evaluate the possibility of increasing growth using microalgae as biofertilizers on seed germination of four commercially important vegetables i.e., radish (Raphanus sativus) subsp. sativus, spinach (Spinacia oleracea), turnip (Brassica rapa) subsp. rapa and fenugreek (Trigonella foenum-graecum). In the current study the fresh biomass of cyanobacterium, Leptolyngbya sp. and green microalga, C. sorokiniana was used as bio-fertilizers to note the effect on seed germination of four vegetables. The In vitro effects of bio-fetilizers were also noted on the different growth parameters i.e., germination percentage, days to germination (50%), plumule length, radical length, fresh weight and dry weight using Randomize Complete Designed (RCD) with factorial arrangement. The results compared with control showed an improved germination percentage using Leptolyngbya sp. (83.17%) and C. sorokiniana (80.47%). Both strains exhibited early germination (4.50 days) while C. sorokiniana showed the maximum plumule (33.88cm), radical length (4.46cm), fresh (1.38g) and dry weight (0.0708g) associated with Leptolyngbya sp. The treatment with B. rapa seed germination was 98.67% and took 1.78 days to germinate. The lowest germination (34.44%) was recorded in S. oleracea and took 6.56 days to germinate. After applying Leptolyngbya sp. on B. rapa and T. foenum-graecum seeds indicated the highest seed germination (99.67%). While B. rapa seeds germinated after one day while primed with C. sorokiniana. The maximum increase over check of germination percentage was observed in Leptolyngbya sp. (11.63%) and C. sorokiniana (8.60%). Both strains improved early germination (3.78%), plumule length (33.88%), radical length (60.31%), fresh weight (7.97%) and dry weight (5.79%). (author)