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The sector of transportation accounts for about one third of the total energy consumption in Switzerland. A monitoring campaign of the energy consumption of a regional train revealed the critical energy-consuming systems. Heating, cooling and ventilation were identified as major consumers. Windows are a source of non-controlled heat transfer. In summer, it may result in overheating leading to larger cooling loads while in winter, it is an important source of thermal losses. Selective double glazing and solar protection coatings can reduce these effects. Angular-dependent optical properties of a selective double glazing have been measured, and the solar heat gain coefficient (g value) was determined. An estimation of the solar gains received by a panoramic waggon was performed using the monitored solar irradiation and the measured properties of the glazing. These data were compared to the heating and cooling energy consumption monitored in this waggon. Solar gains were found to be in the same order of magnitude that the heating energy during some sunny days. They were also compared to the estimated thermal losses through the glazing and the entire envelope. These results show that the solar gains play a non-negligible role in the energy balance of the waggon. Furthermore, thermal simulations were performed to evaluate the solar gains in different conditions. It showed that 7 to 13% of energy can be saved using the glazing adapted to the climatic conditions. In addition, improving the thermal insulation of the train envelope or equipping the train with an efficient heat recovery system can lead to significant energy savings. [ABSTRACT FROM AUTHOR]

This paper presents a back analysis of the time-dependent behaviour of a monitored tunnel in Switzerland. It concerns a specific section of the Mont Terri reconnaissance gallery which was excavated in creeping rock. From a theoretical point of view, Lemaitre''s viscoplastic model was implemented in the FLAC 2D finite-difference numerical code. Particular attention was paid to the stability of the numerical solution for such an explicit mode of resolution. Lemaitre model parameters were successfully fitted on creep tests and then on in situ convergence measurements after a complete numerical simulation. Based on the comparison of strain and stress measured in the lining with the calculated values, time-dependent behaviour can finally be extrapolated over a period of approximately 10 years. Scale effects between results of in situ and laboratory fittings are also discussed. The aim of these investigations is to justify the interest of Lemaitre''s model for the analysis of time-dependent behaviour of underground structures over a long period of time. [Copyright &y& Elsevier]

Novel electrochromic glazing technology has been identified as an emerging option for reducing cooling and lighting electricity demand. As this technology is particularly promising for office building we assess the related technical energy saving potential in case of nation-wide implementation in Swiss office buildings. A Monte Carlo model of Swiss office building stock using distributions of empirical building characteristics was coupled with a statistical model of energy savings of electrochromic glazing. The building stock model for Swiss office buildings was shown to produce cooling and lighting electricity demand estimates in agreement with the existing case study literature. Total yearly electricity demand for lighting and cooling was calculated to be 1152 ± 32 GWh. Electrochromic glazed saved 125 ± 6 GWh or on average 11% of lighting and cooling electricity demand. Electrochromic glazing was found to be particularly effective in highly cooled office buildings, where cooling accounted for 20 kWh/m2 and total electricity saving potential was estimated at 5.5 kWh/m2 or 5.2% of today's typical total electricity demand of an office building across all uses. Areas where electrochromic glazing would have particularly high potential are highlighted. • Assessed the energy saving potential of Electrochromic glazing in Switzerland. • Developed a probabilistic model of cooling systems in non-residential buildings. • Developed a model of potential energy savings from electrochromic glazing. • Total yearly electricity demand for lighting and cooling of 1150 ± 30 GWh was found. • Electrochromic glazing saved 125 ± 6 GWh. [ABSTRACT FROM AUTHOR]

• New method using nodal models developed for evaluating the performance of a box-type solar cooker. • Genetic algorithms used to estimate model parameters that cannot be determined experimentally. • Metric designed to estimate the cooking days potential at the national scale of Switzerland. • Reproducible method means it can be generalized everywhere. Solar cooking is one possible solution to reduce the domination of fossil fuel in the domestic sector and to benefit from renewable energy. This study assesses the solar cooking potential in Switzerland. A nodal model, based on energy balance equations of a box-type solar cooker is implemented in Matlab. Model parameters that cannot be determined experimentally or analytically are evaluated through an optimization procedure based on a Genetic Algorithm (GA). The model is able to predict the temperature of the cooking vessel with an average relative error around 5%. Based on its reliability, the model is simulated over a year for different locations in Switzerland in order to determine the solar cooking potential. It is characterized by a metric that represents the number of days in a year the oven could be used to cook potatoes for two persons. It is found that the cooking times of potatoes can be well predicted by an Arrhenius law with an activation energy of 74.14 kJ mol . The potato cooking criterion is based on the Arrhenius equation and determines if the pot simulated temperature profile of a particular day allows to cook potatoes. The North-East of Switzerland is the least favourable area for solar cooking with theoretically around 155 cooking days per year. Around 240 days are estimated to be suitable for cooking in the cantons of Valais and Grisons, which represents a significant potential for solar cooking in Switzerland. [ABSTRACT FROM AUTHOR]