The presence of the hybrid PV/T system inside a window makes it highly visible from the exterior as well as the interior. One of the basic ideas behind the design was to express the building integrated solar energy system architecturally in an attractive, maximally exposed way. Conceptually, the window is the traditional solar collector, hence an interesting starting point for integrating other solar technologies.

Other aesthetical considerations are mainly due to the reflectors. The curved concentrating geometry is decorative and expresses the capturing nature of a solar energy system. The backside facing the interior could be covered with any surface material suitable for the interior context. The modular nature of the reflectors, with no connection to the energy distribution, makes it possible to exchange them for alternative surface, thickness or reflecting geometry. The concave front facing the window will be highly visible from the exterior, and the mirror like surface might be the most critical aesthetical property for a wider acceptance. However, the curved mirror can generate interesting optical expressions in the fagade.

The extruded picture of the PV/T absorber is visible when the spectator is within the optical acceptance angle range, which means that the impression of the individual modules will differ much in height on a short distance. The overall impression of the fagade will hence change when approaching it. The mobility of the reflectors also contributes to a dynamic fagade expression.

The system is initially intended for experimental integration into a low energy, single family house, designed simultaneously with the concept for the solar window, see figure 2. This house has an 18 m2 south facing window structure prepared for the integration of the Solar Window system. The house is constructed with an EPS module system with integrated load-bearing wooden beams, with no thermal bridges. A central brick wall and a ceramic clad concrete floor absorb passive gains. The solar heating system is complemented by a pellet burner, and the PV system is grid — connected while also carrying a local DC circuit for reducing magnetic fields and eliminating losses in battery eliminators, used for DC powered devices.