The law of energy says no energy can be created or destroyed. Don't count on that law being broken anytime soon.

Free energy would imply that variable costs of converting some energy source into electricity or heat are zero. There is a fixed cost in the building of the device which does the converting. Unfortunately, maintenance is virtually always needed, so there are variable costs.

If in the long run the variable costs (and the spread fixed costs) approximate zero, then you might call the project 'free.'

>>19 Are you sure there are no costs incurred in separating the chlorine and hydrogen? I assume they use regular electricity for that. Meaning that the Hydrogen and Chlorine are merely energy carriers, not energy creators.