grand challenges

Nothing is comparable to the energy from the sun, but we are using only a tiny fraction of capability of solar power. Solar power is alternate energy source which is clean and sustainable in the long run. Current solar cells are offering an efficiency of only 10 to 20 percent, which, when compared with the cost can be very expensive. There are new experiments showing that the use of nanocrystals can effectively increase the efficiency of solar cell to a level of around 60 percent, however, new ideas are needed to transmit energy generated this way into circuit.
One important aspect in solar power development is in making it economical. “This area is where breakthroughs in the science and technology of solar cell materials can give the greatest impact on the cost and widespread implementation of solar electricity,” Caltech chemist Nathan Lewis writes in Science. Material purity is very important so as to maximize flow of current through the cell. There are new system designs in both physical structure and material component to increase the efficiency of solar cell. However, improvements are still needed so that such systems are economical.
While being clean and powerful, we still face problem of storage when we use solar power. Solutions are needed to reserve energy for circumstances when sunlight is not readily available. Technology in energy storage is very important. A possible solution is conversion of energy using sunlight like photosynthesis in plants, so as to produce fuel for energy generation. Another possible is to generate energy out of natural resources, like producing hydrogen from water using solar power. If new catalyze could be found to improve efficiency, the power source could be proved powerful and environmentally friendly.
If we can minimize the cost of solar power, it can make incomparable contribution to our civilization.

References
Lewis, N.S. 2007. Toward Cost-Effective Solar Energy Use. Science 315(5813): 798-801.