Economics of green energy

Why did Warren Buffett pay $44bn for a ticket to ride? - Telegraph

Saw this interesting comment about wind and solar energy (not written by Buffett, though):

Let's not forget that energy storage is quickly becoming a piece of the energy puzzle. As a company which stores and transports unsold energy from wind and solar producers, the train is our "Supertanker", bringing the energy in SeaLift containers to our facilities via road, rail, barge and ship.

Tactical use of stored wind and solar energy is expensive, however, it requires about $360 per linear foot to put in high voltage transmission lines, so even the current $500 per Kwh cost of storage would be competitive, though not very profitable. As the cost of storage is expected to be 1/3 of the current cost in 3 to 5 years, the more volume you can move, the more energy you can deliver-all without nuke, gas or coal plants being built. Many energy "farmers" would otherwise remain "off-the-grid". After storing this energy it can be moved anywhere it is needed and can fetch a higher tariff, like from a wind farm into a major metro area. Perhaps as Mr Buffett owns a mid-American power utility and a chunk of GE and BYD Cars (China), he is also thinking about the future of transportable green energy (which could also power the train BTW) and its by-products.