[ExI] Osmotic power plant

[Henrique Moraes Machado]

<Eugen Leitl> Much more interestingly, you can use a similar process for 
desalination.</Eugen Leitl>

That I knew already. What I didn't know is that you could use this process 
to produce energy. By the feedback on the list however, I noticed that it's 
not an efficient one.

But for desalination, I find the water theater to be a much more elegant 
solution.