Who will decide what will be the most appropriate way to use the energy? There must a way to prioritize the issue.
I think that solar energy is still far from being efficient, and we should focus in increasing yield and improving the technology, so we will not have to worry abount consrvation. Look at the plants - they have a very efficient mechanism to harvest and store the sun's energy, so they only perform photosynthesis for a couple of hours during the day, and they usually do not need to worry about wasting energy!
There is plenty of sun energy out there - we just need to learn how to use it.
