I guess I'm confused on the question. Do you mean from a standpoint of economics or physics? Because there's no such thing as free energy from a physics standpoint, just means to change energy from one form to another. I'm a big proponent of the idea that there's no such thing as a free lunch, and this is what worries me about our global population, every time I see a plausible solution it comes with costs in something else. Energy from this route costs a bunch of water, while fresh water where it isn't plentiful costs a lot of energy to obtain. It's a tough problem to solve, and definitely won't come easy.
So I guess if we're talking economically, I'd say there's no such thing as free energy, and you just have to weigh your time setting up all this crap (assuming it works) to the amount you're paying the electric company to handle it all for you.
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