There are two interesting developments in solar technology I came across awhile ago: The first is a portable solar tracker called Portasol.
The cool thing about this one is that the mechanism for tracking the sun (just like a sunflower would) does not require any power per se. It is thermo-hydraulically powered; click here for Engadget’s explanation of how it works..
The second development is not a solid product yet, but researchers from Georgia Tech have designed a solar cell that can generate electricity when light hits the side of the cell, thus increasing efficiency because it still works well in the morning and afternoon when the sun is not hitting the cell directly from the top.
“It may be intuitive: when the light goes straight down, the only interaction is with the tops of towers and the ‘streets’ below,” says Jud Ready, senior research engineer at the institute’s Electro-Optical Systems Laboratory. “But at an angle, the light has an opportunity to reflect off the sides of the towers.” When the sun is at a 90-degree angle, the prototype delivers only 3.5 percent efficiency. But it delivers better efficiencies at many other angles and is actually at its peak efficiency–7 percent–when light comes in at a 45-degree angle. That means the device operates at relatively high efficiencies during much of the day and has two efficiency peaks: one before noon, and one after noon.
While those efficiencies are too low for commercialization, Ready is working on optimizing the size and spacing of his towers as well as their chemical composition.