Electrolysis?
You mean artificially replicating photosynthesis I think. That's a hell of a task, well to do it efficiently anyway.
As a power source fission is the way to be going until other systems become efficient enough. There have been some developments in altering algae to produce a cellulose that can be turned into ethanol, these organisms theoretically require only 3.5% of the area that would be taken by crops that can be harvested and turned into ethanol. Seems interesting although this has been around since 1998 or something.