Will Solar Powered Planes Just Remain Technology Demonstrators?

Solar Impulse is credited with successful experimentation of the solar-powered planes. Till date, they have developed two prototypes of the solar planes and flown some distance. The plane is a small one with one or two seats and it has flown a remarkable more than 26 hours of intercontinental flight. The plane makes use of the solar panel chips which are used to power it. 

Now, with just single seat, it can be said to be nothing more than a technology demonstrator. The only thing that it has been able to successfully establish is that it is possible to fly using solar energy.

However, while it is a fact that the solar energy can generate a good amount of energy using these solar panels but it is the efficiency of usage of these cells which is the major problem. 

The efficiency with which these panels use solar energy is very less which severely limits the scope of using it. To cite an example, the efficiency level is just 12% which means that if 50000 watts of solar energy is directed on the panels, only about 6000 watts of energy could be created. This needs to be increased significantly and this is nowhere near the desirable mark.

There are two basic ways to generate more power. First is to have more solar panels. Second is to increase the efficiency of these panels. The latter seems a desirable thing to do but is not possible without significant technological improvements. 

The fossil fuels are rather limited and these are also the major cause of pollution. Alternative sources of energy in the form of solar energy can be effective replacements but only on the condition that suitable technology needs to be developed which can enable in efficient harnessing of the solar energy.

So, the question actually is when this technology can be expected to be developed? Will this be developed before certain other alternative fuels which are new and far better than even solar energy? Since man has reached this stage, the next stage can also surely be reached in near future. Aviation is certainly going to change in such a way that the present one will look primitive in future.