It wouldn't have higher power-- that's the point, energy is conserved so you can't bump up the power rate. Work is force over distance, so power is force times speed. If the speed is changed by the flywheel, and the power stays the same (to conserve energy), then it is the force that must vary. Since the "speed" we are talking about is rpm, it's an angular speed, and the force that matters is actually torque (force times radius), as cjl pointed out.

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