Energy Transmission Infrastructure

Ok so here's the theory... There's quite a bit of talk about the transmission problems when it comes to energy. That makes perfect sense considering the current age of the infrastructure and the that sending electricity over a long distance is, generally speaking, a pretty big waste of electricity. Often, renewable energy like solar and wind power can best be generated well away from the civilization that plans to use it, making transmission inefficiencies a huge problem. The analogy that keeps coming to my mind is the counter-intuitive notion that transferring a petabyte of data from New York to Los Angeles would be substantially faster on tapes driven across the country than it would be to send it over even the best fiber-optic connections. Perhaps energy transfer could be done well if generated at a site, but stored in some type of battery, then driven (by truck, by train, whatever) to a kind of collecting station, where the energy would be plugged into the grid and distributed. I assume that battery technology would be and enormous barrier, but I think this is a slightly different problem than the battery problems we are currently focusing on.

As of right now, batteries are apparently not good enough for electric cars to be viable, but there are supposed to be many great strides towards creating a battery which will suffice. Those batteries would be designed for a slightly different function than I envision, so perhaps the storage device needed already exists. Electric car batteries (or fuels cells) are meant to be able to deliver enough power for a car to drive quickly and far, and still be rechargeable/refillable in a short amount of time, as well as working over a long life. Batteries as part of transmission infrastructure would only have to be rechargeable, and hold a substantial charge at full capacity. The time to charge and power delivery would not have to be as quick or as complicated as those in a car.

Another major difference is that there is one or at most several batteries in a car, whereas in this vision of infrastructure, there would be hundreds or even thousands. Each storage device would not have the same size limitations that a car battery would. Obviously there would be some size limitations in the same respect that if a device the size of a suitcase was required to carry 1 GB, the petabyte transfer via physical transportation would not be possible. I'll have to do some research and back-of-the-envelope calculations to figure out just how much energy would have to be stored in a certain space, but my instinct says that the difference in intended function of a battery as part of this infrastructure versus a battery powering a car would be great enough that the technology may already exist.