I used to be Chief Analyst for Starlab an Advanced research lab modeled on the MIT media lab in Europe. I have also spent 2 years researching renewable energy investments for hedge funds etc.
The major issues of energy are storage density, distribution, availability and cost. My own personal storage bias for the future is ultra-capacitors. The energy technology shown below is remarkable in terms of cost, storage potential and the ability to remake the world.
If the technology is stable and distributed it will change the power industry globally and most likely in non-grid dense countries first, where adoption of feasible storage means off grid power from an intermittent source becomes viable. If you sell power why compete with existing infrastructure that delivers @ $.10/KwHr when you can find small off grid villages willing and happy to pay $0.40.
Here is perhaps the most interesting video on energy I have seen in the last 5 years. If you are interested at all about energy it is worth the 20 minutes. Here is the company Sun Catalytix that has been formed to commercialize the technology from Dan Nocera.
Warning this is subtle and the impact won't register with most. ht Paul Kedrosky.