Wind energy is a lot more efficient, the only problem being that its much harder to find a sustainable wind source than a sunny day. Portable wind generators, provided they don’t need a ton of sustained wind would be a huge boon to emerging societies, relief work in remote locations or just being awesome all by your lonesome and blogging on a mountaintop.
While just a concept piece the Eolic looks like it might have a horse in that race. Carbon Fibre and a small footprint could make this an interesting design to watch, and it looks just plain awesome, lets admit it.