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The integrated performance assessment of buildings can orient their design in the early stages. Despite the wide availability of physics simulation-based, data-driven, and hybrid techniques, it is often difficult to rely on a single, appropriate technique to obtain reliable results. A set of methods, each featuring advantages and limitations, help to refine the performance assessment in an iterative comparative process until a comprehensive picture of the building is achieved. The approach was implemented on a nearly zero-energy building, recently built-up as a combined living and office space (e.g., the SolAce unit) on the NEST infrastructure in Dübendorf (Switzerland). The proposed approach showed that the unit reaches high energy performance accordingly requiring optimal cooling management, involving the control of the opening of blinds and windows. A sound convergence between the computer simulations and data-driven analysis were observed, attesting to the overall energy consumption, of around 26 kWh/m2year, in continuous decrease, aiming at an annual energy-positive balance. The unit was ranked first according to the dynamic energy exchange scheme of the energy trading hub within the NEST facility, which features high-level building modules as a testbed of future building technologies. Embodied energy is estimated at 39 kWh/m2year, which is below the commended limits of Swiss eco-building standards. By considering the carbon sequestration of the wood products during their lifespan, the unit is very close to carbon neutrality with the CO2 emitted annually by the unit over its lifetime being compensated by those stored within wood products during the same period.

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Electrochromic (EC) glazing helps manage daylight and solar heat gains in building, thereby allowing a reduction in energy consumption caused by heating, cooling, and artificial lighting. This study relates the optical and electronic properties of nanoporous amorphous molybdenum-doped tungsten trioxide thin films (WO3:Mo) in the pristine state and upon lithiation. When such a film is used as a cathode in EC devices, the color neutrality can be improved with respect to pure WO3, and electrochromic transmission control can be achieved in the full spectral range of solar radiation. In situ x-ray photoelectron spectroscopy reveals that the coloration mechanism is related to the reduction of W6+ to W5+ and Mo6+ to Mo5+. In the initial stages of lithiation, Mo is preferably reduced followed by the reduction of W. Ultraviolet photoelectron spectroscopy highlights systematic trends in the position of the valence band edge and in work function. The occurrence of peaks at 2.2 and 0.8 eV is observed and is related to the formation of partially delocalized Mo5+ and W5+ midgap states. Visible/near-infrared spectrophotometry shows initial absorption mainly in the visible spectral range, followed by absorption in the near infrared. Both absorption bands can be associated with the midgap states due to the occurrence of Mo5+ and W5+, respectively. Lithiation of bilayers composed of WO3:Mo and WO3 shows that the Mo5+ states, which are energetically lower, trap preferentially the transferred charges. Furthermore, our results suggest that lithium ions diffuse rather freely in the direction perpendicular to the substrate. These findings pave the way to next-generation EC devices with color neutral and broadband modulation of spectral transmission and in principle also with dual-band modulation of visible and near-infrared light.