[en] The objective of this work was to design and develop a simulation and multi-criteria optimization tool of energy systems composed of renewable energy (RE) production and storage units. Optimization concerns the systems sizing (renewable production and storage units) and the systems control strategies based on techno-economic criteria. Originality of the tool resides in the modularity of definition of the RE-storage plant architecture, in taking into account several levels of modeling (scale and accuracy) of the different system components and in the consideration of ageing through performances degradation. The developed tool is also illustrated on application cases to highlight its usefulness. (author)

[en] This publication proposes several articles about new methods of production of hydrogen which will support the electric grid (notably the peak and intermittency management) and will allow the storage of low carbon electricity (nuclear and renewable electricity) by 2025 to 2040, depending on the concerned technology. Some of these articles have been presented at a meeting organised by I-tese on the role of hydrogen in energy transition. They notably comment researches performed within the CEA (one of the leader in this field) on hydrogen systems (overview of research programs on the development of new energies, on energy storage to manage wind and solar energy intermittency, on services to electric, gas and heat networks, on decentralised production of low carbon electricity mainly for transport, on biomass valorisation, on hydrogen safety), the interesting potential of hydrogen issued form nuclear energy systems for energy transition, hydrogen as a vector of energy transition, interactions between hydrogen systems and electric systems, and hydrogen as a support to electric grids (literature review, presentation of a model of production and supply of hydrogen by nuclear plants)

[en] Highlights: • Organic matter, SO₄^{2 −} and geological material were the major components of VFPs. • Particle resuspension and chalk dust increased the classroom VFPs concentrations. • High temperature and suspension time of VFPs indoors lead to secondary pollution. • Pb and Mn non-cancer and PAHs cancer risk at school require action from government. Very fine particles (VFPs, PM_0.25) are able to travel deeply into the respiratory tract and can produce adverse health effects, especially to children. Information on the VFPs in schools is generally lacking. We investigated the chemical compositions, sources and health risks of VFPs in a junior secondary school of Xi'an, China, during May 16th to 30th, 2012. The results showed that organic matter (37% and 39%), SO₄^{2 −} (13% and 11%) and geological material (20% and 24%) were the major components of VFPs both outdoors and indoors. The VFP species indoors, such as SO₄^{2 −} and elemental carbon, are mainly from outdoor origins, e.g. coal burning and traffic emissions. But particle resuspension by student activities, chalk dust and import from outdoors of soil dust also contributed to deteriorate air quality in the classroom. By contrast to outdoors, several indoor factors, like higher room temperature, limited volume and longer suspension time of classroom particles, can even lead to significant secondary pollutant production. Heavy metals (mainly from outside) bound to indoor VFPs are supposedly associated to non-cancer health risks, especially Pb through ingestion pathway and Mn through dermal contact. Outdoor VFPs may be associated to PAHs cancer health risks via inhalation way. This study confirms that both indoor and outdoor sources had contributions to indoor VFPs, and that VFPs health risk should be of higher concern in urban areas of Northwestern China.

[en] This document presents existing solutions that combine digital technology and renewable energies. Based on examples, it outlines inhibiting factors to the digital development in this sector, ant also focusses on three key aspects (regulatory aspects, inter-operability, and cyber security). For these purposes, it presents digital technology as an asset for renewable energy projects during their development and design phase (information survey and land prospecting, access to data, simulation and modelling tools, citizen participation), their installation and construction phase (optimisation of works organisation and logistics, and of works controls), and their exploitation and maintenance phase. Then it discusses new stakes for renewable energies in relationship with digital technology: regulations related to digital, data inter-operability between the different actors, data and installation security

[en] Spatial variability of polycyclic aromatic hydrocarbons (PAHs) associated with fine particulate matter (PM_2.5) was investigated in Xi'an, China, in summer of 2013. Sixteen priority PAHs were quantified in 24-h integrated air samples collected simultaneously at nine urban and suburban communities. The total quantified PAHs mass concentrations ranged from 32.4 to 104.7 ng m⁻³, with an average value of 57.1 ± 23.0 ng m⁻³. PAHs were observed higher concentrations at suburban communities (average: 86.3 ng m⁻³) than at urban ones (average: 48.8 ng m⁻³) due to a better enforcement of the pollution control policies at the urban scale, and meanwhile the disorganized management of motor vehicles and massive building constructions in the suburbs. Elevated PAH levels were observed in the industrialized regions (west and northwest of Xi'an) from Kriging interpolation analysis. Satellite-based visual interpretations of land use were also applied for the supporting the spatial distribution of PAHs among the communities. The average benzo[a]pyrene-equivalent toxicity (Σ[BaP]_eq) at the nine communities was 6.9 ± 2.2 ng m⁻³ during the sampling period, showing a generally similar spatial distribution to PAHs levels. On average, the excess inhalation lifetime cancer risk derived from Σ[BaP]_eq indicated that eight persons per million of community residents would develop cancer due to PM_2.5-bound PAHs exposure in Xi'an. The great in-city spatial variability of PAHs confirmed the importance of multiple points sampling to conduct exposure health risk assessment. - Highlights: • Strict motor vehicle emission control measures can be benefited to both urban and suburban air quality. • Green city plan bearing urban capacity favors a clean atmosphere. • New air pollution purification technology and advanced management improve air quality. • Eight cancer cases per million of residents could be attributable to PM_2.5-bound PAHs exposure. - Inefficient control of vehicle is the most significant contributor to the suburban PAHs. Eight cancer cases per million of residents could be attributable to PM_2.5-bound PAHs exposure.

[en] Seasonal variation and spatial distribution of PM_2.5 bound polycyclic aromatic hydrocarbons (PAHs) were investigated at urban residential, commercial area, university, suburban region, and industry in Xi'an, during summer and winter time at 2013. Much higher levels of total PAHs were obtained in winter. Spatial distributions by kriging interpolations principle showed that relative high PAHs were detected in western Xi'an in both summer and winter, with decreasing trends in winter from the old city wall to the 2^nd-3rd ring road except for the suburban region and industry. Coefficients of diversity and statistics by SPSS method demonstrated that PAHs in suburban have significant differences (t < 0.05) with those in urban residential in both seasons. The positive Matrix Factorization (PMF) modeling indicated that biomass burning (31.1%) and vehicle emissions (35.9%) were main sources for PAHs in winter and summer in urban, which different with the suburban. The coal combustion was the main source for PAHs in suburban region, which accounted for 46.6% in winter and sharp decreased to 19.2% in summer. Scattered emissions from uncontrolled coal combustion represent an important source of PAHs in suburban in winter and there were about 135 persons in Xi'an will suffer from lung cancer for lifetime exposure at winter levels. Further studies are needed to specify the effluence of the scattered emission in suburban to the city and to develop a strategy for controlling those emissions and lighten possible health effects. - Highlights: • PM_2.5 bound PAHs were investigated in nineteen communities of Xi'an at 2013. • High amount of uncontrolled coal combustion were happened in suburban at winter. • About 135 persons in Xi'an will suffer from lung cancer for exposure at winter. - The high contribution of coal combustion for PAHs in suburban region demonstrated the high amount of scattered emissions in winter.

[en] This special issue of Clefs CEA journal examines CEA's involvement and achievements in the field of low-carbon energies. Content: 1 - Foreword; 2 - The power of the concept of energy; 3 - Searching for the ideal energy mix; 4 - Electrical energy and CO₂ emissions; 5 - The nuclear sector post-Fukushima; 6 - The nuclear life cycle: the nuclear fuel cycle, Cleanup and dismantling of nuclear facilities; 7 - Astrid, Generation IV advanced sodium technological reactor for industrial demonstration; 8 - Fusion, an energy source for the future; 9 - Photovoltaic solar energy: Photovoltaic technologies and centralized electricity production, Decentralized electricity production - solar energy integrated into the building, Concentration photovoltaic; 10 - Concentrated solar power - the other alternative for electricity production: Concentrating the Sun's energy, The promise of thermal storage; 11 - 2. generation biofuels: the Syndiese project; 12 - Microalgae for the production of biofuels; 13 - Areas of R and D at CEA for developing economically and socially viable low-carbon energies; 14 - Energy in batteries: Batteries for electrical mobility, Batteries for stationary applications, Optimizing lithium battery safety; 15 - Hydrogen, an inexhaustible energy carrier: Storage of hydrogen, Hydrogen - a means of storing electricity; 16 - Smart grids - when electrical grids become intelligent; 17 - Solar mobility; 18 - Green chemistry, biocatalysis and biomimetics; 19 - Nanosciences and nanotechnologies working for energy; 20 - Electric transports, The competitiveness of electric travel; 21 - Improving energy performance in the home; 22 - Using nuclear heat for non-electric applications; 23 - Institutions and organizations: who does what? 24 - Glossary.