Electromagnetic energy to Chemical energy
You can certainly turn electromagnetic energy into chemical energy, but the key is 'efficiently.'

A photo-voltaic cell can be used to split water into Hydrogen and Oxygen. The Hydrogen can be burned or used in a fuel cell.

But the key is how efficient is 'efficient.'

Each step will lose energy, but if solar is the input, there is a huge supply. If a solar powered system were continually operating, and we had many of these systems, a huge amount of Hydrogen gas can be generated. Even considering the costs of delivering to where it is needed (which can be paid with the product itself) there is a huge and realistically limitless supply. 

That being said, there is much 'waste' which hampers a calculated efficiency, but once established a system that relies on water for a raw material is relatively efficient because there is very little required for raw material acquisition.