Why not Solar Energy

The quest and hunger for the resources of energy is getting so much out of hands that we have even stopped thinking all the consequences this world is facing. We are driving ourselves towards destruction so fast and so blindly like never before. All the wars, all the cheap politics all the greed is for Oil. What will be the outcome if we can only invest just a small portions of those billions and billions of dollars in to other forms of alternate energy sources. The biggest and probably one of the most abundantly available in world is Solar energy. What is stopping all these big companies in investing in the research? Why not put more and more time and effort into exploring this option. It is definitely much cleaner than oil and coal and Nuclear why not put all the efforts in exploring it. Here we are facing the biggest challenges of our time politically, economically, financially so why not invest in something for which we won't have to fight wars, we won't have to destroy our only home, our only planet Earth?