In this paper, we study tungsten oxides deposited by reactive magnetron sputtering. The total working pressure during deposition was varied in order to obtain different morphology. The effects on the electronic properties and chemical composition were studied by XPS and UPS. It was observed that, for the same argon to oxygen ratio in the gas feed, the decrease in total working pressure implies a decrease of the oxygen content in the film. In the nearly stoichiometric WO 3 films, W 4f 5/2 and W 4f 7/2 form a distinct doublet peak. In sub-stoichiometric films, the films do not exhibit a well-resolved doublet and suggest multiple oxidation states of tungsten.The valence-band spectra of the sub-stoichiometric samples present an additional feature below the Fermi edge (~0.5 eV). This peak is assigned to W 5d 1 because of the presence of W 5+. It is consistent with the changes on the corelevel spectra. XPS results, UPS features, and visual aspect are in agreement and suggest that the total working pressure has a strong influence on the oxygen content and therefore on the oxidation state of tungsten in the films.

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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 nationwide 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±32GWh. 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 20kWh/m 2 and total electricity saving potential was estimated at 5.5 kWh/m 2 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.

A real case study and characterisation of modern energy efficient windows allowing mobile communication is presented. An earlier study had shown that laser scribing of energy saving coatings allows highly reducing the microwave attenuation (from 30 to 1-3 dB) using a wide band-pass frequency-selective surface (FSS) while preserving the thermal quality of the window. To achieve large-scale production, the laser scribing technique has been further developed. The effect of laser scribing on the mechanical properties of a substrate has been determined through mechanical strength tests. Moreover, the insulating properties of the window have been analysed to ensure the reliability of this technology. As a real case demonstration, an entire train has been equipped with prototype windows. The signal quality has been controlled for a wide band of frequencies and for existing technologies such as long term evolution, universal mobile telecommunication system, multiple input multiple output and for different configurations such as a stationary and a moving train.

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