Science Daily has an article on using electrofluidic cells to increase the amount of lighting available from windows - Bringing Sun's Light and Energy to Interior Rooms: Innovative Solar Technology May Lead to Interior Lighting Revolution.
There's a simple question SmartLight addresses: Is there a smarter way to use sunlight? Every day the sun's rays hit Earth with more than enough energy to meet many of society's energy demands, but existing technologies designed to harness that energy, such as photovoltaic cells, aren't very efficient. A typical photovoltaic array loses most of the sun's energy when it gets converted into electricity. But with SmartLight, Harfmann says the sunlight channeled through the system stays, and is used, in its original form. This method is far more efficient than converting light into electricity then back into light. ...
SmartLight could help shift that energy imbalance. It works like this: A narrow grid of electrofluidic cells which is self-powered by embedded photovoltaics is applied near the top of a window. Each tiny cell - only a few millimeters wide - contains fluid with optical properties as good or better than glass. The surface tension of the fluid can be rapidly manipulated into shapes such as lenses or prisms through minimal electrical stimulation - about 10,000 to 100,000 times less power than what's needed to light a traditional incandescent bulb. In this way, sunlight passing through the cell can be controlled.
The grid might direct some light to reflect off the ceiling to provide ambient room lighting. Other light might get focused toward special fixtures for task lighting. Yet another portion of light might be transmitted across the empty, uppermost spaces in a room to an existing or newly installed transom window fitted with its own electrofluidic grid. From there, the process could be repeated to enable sunlight to reach the deepest, most "light-locked" areas of any building. And it's all done without needing to install new wiring, ducts, tubes or cables.