I am considering using a flywheel to power a machine for an indefinite period of time. I intend to bring the flywheel up to operating speed by manual means. Once the flywheel is rotating at operating speed, a motor will be used to keep the flywheel rotating. In order to maintain the operating speed of the flywheel for an indefinite period of time, will the motor be required to supply as much energy as it took to get the flywheel up to speed, or will the energy requirement placed upon the motor be reduced somewhat by the momentum of the already rotating flywheel? Thanks!