Known as luminescent solar concentrators (LSC), these devices so far haven't proven as efficient or scalable as regular panels, but now a team at Los Alamos National Laboratory has demonstrated a new technique that could make for larger, more practical solar energy-harvesting windows.

The key to LSCs are molecules known as flurophores embedded within the glass surface, which absorb the light that hits them and re-emit it as lower energy photons. These photons are then guided to the edges of the surface, where strips of conventional PV cells lie in wait to catch them. Over the years, the technology has advanced from visibly studded sphelar cells, to semi-transparent tinted windows, right up to fully transparent planes of energy-producing glass.

The problem is, aesthetically and practically, clear glass would be ideal. Yet those devices can lack in the efficiency department, converting just one percent of the solar energy received.