Energy surplus

Say energy plants produce energy that is stored in massive city sized batteries, and cities get their energy from these batteries.  You can extend these "battery" plants indefinitely, limited only by how much space they take up and how energy they store in that space.  You can extend this to island batteries, battery complexes in remote parts of the world, and space battery stations.  Any type of energy can go in, so solar, hydro, coal, gas, and nuclear can all add to storage. 

What would be wrong with this system?  What would make it innefficient?  What amount of energy would be wasted in energy transportation, storage life, and redistribution of energy (a middleman instead of directly from the plant).  How long could you keep surplus battery energy?  Could you store enough to offset any losses in efficiency? 

Your energy transmission cost would be extensive.  How do you get energy to and from satellite batteries?  How do you transmit energy across oceans in its "electrical" form?

One of the reasons energy generation is always done locally is because of the inefficiencies of transmission.  If transmission were efficient across oceans, we'd do it.  It turns out that it's much more efficient to transport energy in its concentrated form (aka fuel) than to transport energy in its electrical form.

How would you generate all this surplus energy?  Where would you build your power plants?  What sorts of power plants would you build?  Where would you get the money to do it?  How would you convince the entire state of Cali-"Not in My Backyard"-fornia to  go along with your idea?  Remember that you want power plants geographically close to the major energy consumption nodes to minimize loss due to transmission inefficiency.

Your proposal is fundamentally flawed.  Your questions imply that you're getting way ahead of yourself.  Don't worry about storing enough to offset losses due to inefficiency when you haven't supplied a scenario for generating sufficient power.  Remember that there are *reasons* all of the cutesy "earth-friendly" power plants don't get built.  Nobody's willing or able to foot the bill, few people will pay the extra $.10/KwH for "green" energy on their home bill, and very few communities are willing to allow the construction of any sort of power plant in their communities.  Windmills, after all, are great big bird-blenders.  Hydroplants destroy spawning grounds because fish have a hard time getting through or get chopped up.  Nuclear power is irrationally feared because morons think that the clean steam flying out the cooling tower is radioactive (duuuuh), and I don't think I have to explain why no one wants coal and oil plants in their neighborhoods.

And this is just a basic layman's problems.  I'm sure politicos could come up with a dozen more issues regarding the int'l cooperation that'd be required for something like this.