A team at Massachusetts Institute of Technology (MIT) led by, among others, Professor Marc Baldo, has devloped a solar PV concentrator system which uses large glass panes with PV cells round the edges. That way you can have a big collector area but fewer cells. The new technique involves coating glass with a specific mixture of transparent dyes, which redirect light to photovoltaic cells in the frame edge. The technology, outlined in the journal Science, could be used to convert glass buildings into energy generation systems.