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Abstract The price effect of the rising share of renewable electricity, which is called ‘merit-order-effect’, leads to noticeable changes in the German power industry and debates about the electricity market design. This paper estimates the merit-order-effect induced by variable renewable energy in the German-Austrian electricity sector with a multivariate regression model. The research focus lies on the impact of the estimated effects on the marketability of variable renewable electricity generation. The results show a systematic decline of the average market revenues for wind and photovoltaic plants in the period from January 2011 to December 2013. Current market data shows a continuation of this trend into 2016. According to the German long term goals for the use of renewables, wind and solar power will play a crucial role in the future electricity generation mix. If investments in these technologies will be profitable without any regulatory remuneration mechanisms in addition to the market revenues, depends on the further cost degression and the development of the merit-order-effect.

Abstract Social acceptance of innovative technologies is a key element of an effective transition towards more sustainable energy economies. However, innovative technologies like genetic modification also tend to spark controversy and backlash. So far, efforts to inform the public about any risks and benefits of novel technologies not only have struggled to foster acceptance but also neglect the interdependent foundations of consumer decision-making. Through a controlled experiment with German consumers (N = 322), we examine whether consumer support and rejection of genetic modification in bioenergy crops is influenced by the statements and actions of actors throughout the supply chain. In specific, we show that the decision of energy companies to sell and support GM bioenergy positively impacts consumer decisions to support. To ensure that decision outcomes were specifically impacted by the expressions of corporate actors, we controlled for the content and valence of information by random assignment to one of three treatments in which participants received positive, negative, or balanced (risks and benefits) information. We find that negative messaging diminished support and increased rejection relative to the other treatments. Lastly, the statements and actions of corporate actors also exerted an indirect influence on consumer decisions through their interactions with social trust and labels, e.g. greater support by farmers had a positive influence only for those who are more generally trustworthy. Given these results, we anticipate more attention to the importance of actors such as farmers and energy companies for the social acceptance of novel technologies in the energy sphere.

Abstract— The odd nucleoside 4‐thiouridine, which is present in position 8 of 70% of E. coli tRNAs, possesses unusual spectroscopic properties which make it suitable for intramolecular energy transfer studies. Both its luminescence excitation spectrum and the action spectrum (230–380 nm) for the 8–13 link formation have been established in native E. coli tRNA at room temperature. The spectra are identical and present a new unexpected peak around 260 nm. At this wavelength, they are amplified by a factor of nine as compared with the absorption and excitation spectra of the free nucleoside in aqueous solution.The origin of this new peak is discussed and it is concluded that energy transfer does occur from the common nucleosides to the 4‐thiouridine residue. Using the values of the nucleosides to 4‐thiouridine distances inferred from the sets of atomic coordinates obtained on yeast tRNAphe crystals, a satisfactory account of our finding can be obtained assuming singlet‐singlet energy transfer. The efficiency of the mechanism is probably favoured by a good overlap between the emission spectra of the common nucleosides and the absorption spectrum of 4‐thiouridine.

Abstract An international workshop was held in Richland, Washington, United States of America, in October, 1980 to discuss progress on development of the acid digestion process for treating combustible nuclear waste. The workshop was attended by participants from nine member countries of the Nuclear Energy Agency of the Organization for Economic Cooperation and Development (OECD/NEA). The status of the acid digestion development programs of various countries is discussed in this paper. The acid digestion process has been developed and demonstrated on an engineering scale in several countries and appears to be especially applicable to treatment of combustible wastes containing high levels of transuranic contamination, where there is potential for recovering the transuranic radionuclides. Because the process takes place at a relatively low temperature, the plutonium contained in the residue is in a form that can be readily recovered using standard leaching techniques. The process is adaptable to a wide variety of combustible wastes, such as cellulosics, plastics, rubber materials, and ion exchange resin. While the process has been developed and demonstrated on an engineering scale primarily for transuranic contaminated wastes, the process is also adaptable to beta-gamma wastes such as reactor ion exchange resins.

Abstract This paper describes the point of view of a gas utility regarding systems for cooling and heating by solid sorption. Indeed, the context is favorable to the emergence of such systems first, of course, due to the regulatory constraints on certain refrigerant fluids, but also for their specific technical characteristics (the storage capacity, for example). The gas utilities have in fact shown an increasingly keen interest in all types of sorption systems, as a way of diversifying natural gas utilization, particularly in the summer. After a review of that context, this paper highlights the advantages of solid sorption and describes the criteria for choosing an installation in air conditioning and cooling production applications. Finally, it discusses the difficulties likely to be encountered in developing sorption systems, as well as the prospects for the future.

Cogeneration of heat and electricity is an important pillar of energy and climate policy. To plan the production and distribution system of combined heat and power (CHP) systems for residential heating, suitable methods for decision support are needed. For a comprehensive feasibility analysis, the integration of the location and capacity planning of the power plants, the choice of customers, and the network planning of the heating network into one optimization model are necessary. Thus, we develop an optimization model for electricity generation and heat supply. This mixed integer linear program (MILP) is based on graph theory for network flow problems. We apply the network location model for the optimization of district heating systems in the City of Osorno in Chile, which exhibits the “checkerboard layout” typically found in many South American cities. The network location model can support the strategic planning of investments in renewable energy projects because it permits the analysis of changing energy prices, calculation of break-even prices for heat and electricity, and estimation of greenhouse gas emission savings.

Abstract Amorphous and microcrystalline silicon single layers and p–i–n solar cells were produced dynamically using an inline deposition system called “line source”. A highly uniform deposition of thin-film silicon layers with layer-thickness variations of less than ±5% was achieved. Amorphous and microcrystalline silicon single junction solar cells were dynamically fabricated with initial efficiencies of 8.3% and 6.3%, respectively. The dynamic deposition rate of these solar cells is 6.75 nm m/min in case of a-Si:H and 3.3 nm m/min for μc-Si:H. In this work it will be shown that an enhancement of the deposition rate up to 15.6 nm m/min during the i-layer deposition of a-Si:H solar cells has only a weak negative influence on the initial efficiencies of the cells. Further on, the effect of substrate velocity on solar cell characteristics of a-Si:H solar cells is investigated. Finally, a productivity estimation of the line source concept is presented.

Abstract This paper deals with an optimization of the Stirling engine regenerator’s. Firstly, different materials are experimented (Stainless Steel, Copper, aluminum and Monel 400). The engine performances and the state of each material after 15 h of use are considered. The Stainless steel was the material that best satisfies these two conditions. Five regenerators in stainless steel with different porosities were manufactured and experimented (95%, 90%, 85%, 80% and 75%). Porosity that gives the best trade-off between maximizing the engine brake power, maximizing the heat transfer and minimizing the pressure drops, was retained. Thus, the regenerator in stainless steel with porosity of 85% was considered as the most suitable matrix maximizing the Stirling engine performances and minimizing heat and friction losses.

Abstract Solutions containing hydrofluoric acid (HF), hydrochloric acid (HCl), and hydrogen peroxide (H2O2) were investigated as novel acidic, NOx-free etching mixtures for texturing of monocrystalline silicon wafers. High etch rates of up to 13.3 nm s−1 were observed at room temperature, which are comparable to the etch rates of KOH-IPA solutions. The silicon surface was investigated by scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM), indicating pyramidal textures for diamond wire and SiC-slurry sawn as well as saw-damage etched (polished) wafers. Non-stirred baths generate random pyramidal structures while constantly stirred solutions generate novel random inverted pyramidal surface structures. The light trapping efficiency of wafers etched by the HF-HCl-H2O2 solutions was compared by UV/vis-reflectivity measurements to KOH/i-propanol specimens indicating lower reflectivities for the HF-HCl-H2O2-treated samples. Using the ‘wafer ray tracer’ (pvlighthouse.com) the light absorption properties of monomodal and random inverted pyramid structures were simulated and compared to well-known random and monomodal textures for PERC solar cells, clearly indicating the best performance for random inverted pyramids. Besides, simulation of a PERC solar cell on a roof top at our university was performed, indicating improved performance, especially for random inverted pyramid textures.

This study investigates the feasibility of a device to improve summer comfort in wood-frame houses using a Ventilated Internal Double Wall (VIDW). The idea is to increase the house's thermal inertia and to evacuate accumulated heat during the night with a mechanical ventilation system. The VIDW is a cooling wall. Numerous studies on night ventilation have been conducted, but the active ventilation inside the air gap of a double wall with high thermal inertia has not been studied. The first part of this study examines the impact of VIDWs on the thermal comfort in a timber-frame house. The VIDW is modeled in transient mode based on an electrical analogy with the assumption that the exchange coefficients are constant for a given air velocity. In addition, modeling a stationary CFD in forced convection of the VIDW air gap allowed us to study the cooling potential and the benefit of installing obstacles.