The luminescent solar concentrator (LSC) could provide a colorful and adaptable complement to standard silicon solar panels, allowing easier deployment solar energy systems in the urban environment. In order to successfully implement this technological innovation into the built environment, it should also complement the surrounding architecture and be visually acceptable to the user. One prominent feature of the LSC is its bright, fluorescent coloration. Since the devices can be transparent, this opens the possibility of employing the LSC as a power-generating window. Current research on LSCs focused on the energy efficiency and on the theoretical impact on users. So far, the impact of such a colored window on the inhabitants (or users) in spaces using these windows has been largely unexplored. In this work, we study the impact of a red LSC on the visual comfort and impression of volunteer participants. We made the interesting observation that a window covered 25% by an LSC is judged favorably when compared to a normal, clear glass window. Such a window could become a local source of electrical power from sunlight while simultaneously improving the well-being of the room inhabitants. (C) 2015 Elsevier B.V. All rights reserved.