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[en] In recent years, plasma-induced non-equilibrium electrochemistry (PiNE) has been increasingly used for the synthesis of nanomaterials. In this study, we investigated the effect of solution pH on the formation of AuNP/MWCNT nanocomposites synthesized by PiNE. It is found that resulting nanocomposite morphology can be manipulated by the solution pH with pH 2 giving the most uniformly distributed AuNP along the MWCNT surface during the nanocomposite formation. The detailed mechanisms of AuNP/MWCNT nanocomposites formation under different pH have been discussed. For selected AuNP/MWCNT, we further evaluated the photothermal conversion performance under a blue laser (wavelength 445 nm) and the material biocompatibility using HeLa cells. The promising photothermal capability and biocompatibility of the composite sample point to their potential future applications such as solar thermal conversion and healthcare technology. (paper)
[en] Under the current macro-economic trends, the so far abundant support system for renewables (mainly in the form of feed-in-tariffs and quota systems) has been drastically modified. In many EU countries, companies are trying to find alternative ways to secure financing for their renewable energy projects. Therefore, new ways of attracting private capital for the realisation of green energy goals have to replace the old schemes. Some new forms of financing are coming together with the EU Cohesion Policy 2014-2020 (project guarantees, packaging of small project for micro-financing schemes at the regional level, preferential loan instead of subsidies etc.). Advanced financial structures are likely to play an increasingly important role in the allocation of risk and reward among different investor classes. The finance and investment gap needs to be filled by the private sector. The challenge is to identify the appropriate policy options and financial tools to attract and scale-up private investments. There are, however, already innovative and promising business and financial models to promote the deployment of RES in the EU. The aim of the EurObserv'ER case studies is to find such examples and describe them so as to put forward the best practices and the replicability of the future promising financing mechanisms. EurObserv'ER will aim at choosing only the most promising ones and try to describe them in order to promote replicability in other geographical areas. The selection criteria for the choice of case studies should ensure (i) diversity across regions and RES, (ii) diversity across finance instruments/mechanisms, (iii) success of approach and its potential to be replicated, (iv) and a wide range of the 'size' of actors/ investors and the resulting RES investments (capacity). The current selection also takes into account the fact that there were already some case studies published in 2014, 2015, 2018 and 2019. These are also available for download on the project web site: www.eurobserv-er.org
[en] The transformation of the global energy supply is taking place primarily in the accelerated growth dynamics of the increasing share of renewable energies for power generation. In the last decade, renewable energies accounted for more than 60% of the total investments made worldwide in power generation each year. The capacity of power generation plants based on solar, wind, hydro, bio, geothermal and ocean energy more than doubled between the end of 2010 and the end of 2019 - favored by government subsidies and a strong cost degression. In the course of this development, the share of renewable energies in global electricity generation has steadily increased and reached a new record level of 26.0 % in 2019. This means that renewable energies are now - after coal - the second most important source of energy for electricity supply.
[de]Die Transformation der globalen Energieversorgung findet vor allem in der beschleunigten Wachstumsdynamik beim Ausbau erneuerbarer Energien zur Stromerzeugung statt. Auf erneuerbare Energien entfielen im letzten Jahrzehnt jedes Jahr über 60 % der gesamten Investitionen, die weltweit in der Stromerzeugung getätigt wurden. Die Kapazität der Stromerzeugungsanlagen auf Basis von Sonne, Windenergie, Wasserkraft, Bioenergie, Geothermie und Meeresenergie hat sich von Ende 2010 bis Ende 2019 - begünstigt durch staatliche Förderung und eine starke Kostendegression - mehr als verdoppelt. Im Zuge dieser Entwicklung hat sich der Anteil erneuerbarer Energien an der globalen Stromerzeugungsmenge stetig erhöht und 2019 einen neuen Rekordstand von 26,0 % erreicht. Damit sind erneuerbare Energien inzwischen - hinter Kohle - die zweitwichtigste Energiequelle zur Stromversorgung.
[en] In this review work, energy harvesting methods for waste heat with small temperature differences between heat source and sink are discussed. At present, many methods are tried and employed to utilize this type of waste heat. A typical example is found in a conventional power generation system. By utilizing this type of waste heat, additional energy can be produced in regular power generation systems. Up to this point, two energy harvesting methods have been introduced and applied for the use with this type of waste heat. One is a method using an organic Rankine cycle (ORC) while the other is a method using a thermoelectric generation (TEG). An ORC is a Rankine cycle that can be applied to this type of waste heat using organic fluids such as refrigerants as working fluids instead of water used in a typical Ranking cycle. On the other hand, a TEG utilizes Peltier, Seebeck, and Thomson effects caused by the temperature difference between the heat source and sink for energy harvesting. In this work, various aspects associated with the use ORC and TEG for waste heat harvesting with small temperature differences between the heat source and sink.
[en] The European Union solar thermal market for heat, heating, and domestic hot water production held up well in 2019. Initial estimates put the total installed collector area at just under 2.3 million m2, which is a slight increase (1.5%) on its 2018 level. However, individual country situations vary, and the sector still has to reinvent itself to meet the huge challenge of climate neutrality. The term Concentrated Solar Power (CSP) covers all the technologies that aim to transform solar radiation energy into very high temperature heat to convert it into electricity. Most of the current CSP development is going on in countries and regions that offer suitably conducive sunlight conditions, such as China, India, Australia, South Africa, the Middle East, and the Maghreb. The European Union's new CSP plant installation pace slowed down considerably after an initial flurry concentrated in Spain between 2007 and 2014. In 2019, the European Union gauge moved up slightly to 2 323 MW when the eLLO project in the Pyrenees-Orientales, France, officially came on stream.
[en] In regions of hot and dry climate, as in part of the north, northeast and central-west regions of Brazil, intense solar radiation in buildings increases the consumption of electrical energy with air conditioning, especially in buildings with low thermal resistance fences. Although in Brazil the energy matrix uses mainly renewable sources, the impacts of the implantation of the plants are not negligible. Bioclimatic architecture offers passive solutions for thermal comfort in buildings with low investment, low maintenance and good thermal efficiency. In this context, a bioclimatic residence was built, applying different compositions of walls to evaluate their thermal properties in a real scenario. This work evaluated the internal and external temperatures of each type of wall composition for one year. Other physical parameters, such as relative humidity, solar irradiance and paint reflectance were also measured and analyzed. Costs and savings were calculated in a brief feasibility study, pointing to thermal insulation with Expanded Polystyrene (EPS) as an affordable solution to the heat problem caused by sunlight and the consumption of electrical energy with air conditioning. (author)
[en] Illustrated by many maps, graphs and tables, this publication proposes a rather detailed overview of the status and development (production and location, employment, sector turnover, market and tariffs) of the different electricity-producing renewable energies: wind energy, photovoltaic energy, hydraulic energy, solid biomass, biogas, renewable urban wastes, geothermal energy, marine energies, thermodynamic solar energy). This issue includes a special focus on electric mobility. It proposes also a regional overview of these different electricity-producing renewable sectors. A focus is proposed for each French region