Alcradia: sagas of battle/Spiral power

Power has always been produced by rotating a magnet and a metal coil relative to each other. But, like everything else, it is not 100 percent efficient. The laws of thermodynamics get in the way of pure 1-to-1 energy generation. That is without magic.

When wind magic is cast in a circular motion, it would retain its momentum with remarkably little energy loss, surpassing the efficiency of any other known energy storage system in existence. Anything that requires rapid circular motion, from buzz-saws to jet turbines to drills, could be improved by this magic. Despite the fact it cost a large amount of chi to maintain it and the efficiency isn't an absolute exchange. Leading to spiral based engines, which uses high powered winds to move, with and only slightly inferior to a standard diesel engine for power to weight but more renewable.

This was a godsent to the Navaheim. Who were gifted in arcane magic, particularly wind type, but had little to no fuel to properly use conventional engines. Instead having all of their vehicles, ships, and aircrafts utilizing spiral engines to move, making them cheaper compared to conventional vehicles. But, due to it needing to be larger then a conventional engine to give comparable power, many of their vehicles either need to be made of light materials or thin armor.