Millions of surfaces are now being literally wasted in terms of energy harvesting when they don't have the necessary technology for it. For instance if a skyscraper is completely covered with glass materials with direct contact with sunlight, and it has in them an efficient methodology for using the upcoming energy, the results would be astonishing as some of them have a huge surface. That way the skyscraper would be converted in a solar panel and when a roof of a medium sized home is practically or completely enough for the energy needs if it has installed solar panels on it, with the skyscraper in that way the energy output should even surpass the necessary power.
Also, any portable device that has a screen also has a transparent glass or plastic that protects it. The same for these devices; the Sun could be sometimes the unique source for charging the device.
With transparent materials the most straightforward idea is to use several layers to increase efficiency. Multiple leaves are translucent and permit others to take "second hand" energy. Other time here Nature provides examples.
The task is more or less a challenge today but there are new materials in the palette like graphene, organic semiconductors, ..., and the state of the art nowadays includes nanotechnology at (tiny) considerable proportions. So, why not?
This is an exciting field that has fantastic advantages on it, especially good for research. In the year 2011 the transparency was at 60% with 2% efficiency using silver materials. Some recent focus on this.