Japan Energy Champions, Tokyo Sky Tree

I was writing two weeks ago about the Japanese companies making efforts to alleviate the current energy crisis... But efforts to reduce power consumption and to use environmental friendly systems started even before the crisis.
Tobu Railways, the operators of Tokyo Sky Tree, recently presented the tower's heating and cooling system, based on a solution which reduces the energy consumption by an amazing 40-50%!

Basically, this system stores the water used for cooling during summer / heating during winter in 4 huge, 7000 tons underground tanks (that means the equivalent of a 17x25 meters pool). That way, the water will be cooled / heated during off-peak times and will also be more easily maintained at the desired temperature...