If you have the interest, study nanotechnology. You'd be amazed by the possibilities it have. Last day i had a presentation on 'MEMS based Solar Harvesting', using the IR spectrum of the solar radiation to generate electricity using Piezoelectric property of PZT. And it's cheaper to fabricate than Photovoltaic cells and can be used in tandem with existing PV Cells, where it'd take the thermal energy from solar cells and generate electricity.
By this method, we can have a efficiency of around 40%, making solar energy cheapest of all existing power sources. Current efficiency is around 10-15%.