In biology, any group of fish that stay together for social reasons are said to be shoaling, and if, in addition, the group is swimming in the same direction in a coordinated manner, they are said to be schooling.
Fish derive many benefits from shoaling behaviour including defence against predators (through better predator detection and by diluting the chance of individual capture), enhanced foraging success, and higher success in finding a mate. It is also likely that fish benefit from shoal membership through increased hydrodynamic efficiency.
This theory states that groups of fish may save energy when swimming together, much in the way that bicyclists may draft one another in a peloton. Increased efficiencies in swimming in groups have been proposed for schools of fish and Antarctic krill.
Professor Dabiri from the Center for Bioinspired Engineering of Caltech (California Institute of Technology) and his team drew inspiration from fish behaviour within schools to develop a system that could "demonstrate an alternative approach to wind farming that has the potential to concurrently reduce the cost, size, and environmental impacts of wind farms".
A big issue in designing wind farms is indeed that of the needed distance between different wind mill, which often might result in a landscape eyesore. Further study on this topic might help making wind energy plants more common and accepted.
Source : http://www.nationalgeographic.it/ambiente/2012/04/21/foto/energia_dalla_natura-978663/9/