Galvanic batteries are constructed using voltaic cells.
Voltaic cells are constructed using two dissimilar metals and an acid, alkaline, or salt solution. An Earth Battery is a form of voltaic cell. An Earth Battery is a pair of electrodes, consisting of two dissimilar metals, using moist earth as an electrolyte. To make the battery, bury plates of zinc (anode) and copper (cathode) in the ground about a yard apart. It will produce an output voltage of approximately 1 volt.
This seems like an Earth Battery concept with a twist. There are probably a number of problems with this idea... I would like to make a list of potential problems.
Potential Problems
1. Voltaic cells are constructed using two dissimilar metals and an acid, alkaline or salt solution.
2. Earth Batteries do not generate much energy.
If you were to substitute the moist earth as the electrolyte for the ocean as a salt based solution then you would have to stick the metal plates into the water. If you stick the metal plates into the Earth, then you're effectively using the moist Earth as the electrolyte instead.
Either way, realistically, I don't think you would end up tapping into a power reservoir. It's more effective to use hydroelectric power or geothermal power to generate electricity using the earth and sea.
