Magnetic Gears? The Key to Efficient Ocean Current Energy Recovery

Given that the earth is more than 70% covered by water, the potential for converting these renewable resources to electricity is many times that of other resources. In the conversion of wave and water-current energy to electrical energy, gears are used as a convenient way to convert the slow-speed, high-torque water energy to a high-speed, low-torque counterpart. However, mechanical gearboxes are beset by life and maintenance issues. For direct-drive conversion, the equipment is huge both in physical size and in cost, due to the properties indigenous to the materials available and practical today. This project will explore the replacement of mechanical gearboxes with magnetic gears. Calculations suggest that a magnetic gear with a 1/50th sized conventional generator could replace an electromechanical system 8 times larger. Phase I will optimize a 10 kW flux divertor (shutter) gear design, perform life cycle estimates on the bearing loads, and develop a plan for designing an optimal magnetic gear design to advance wave and current energy technologies. Commercial Applications and other Benefits as described by the awardee:The technology development should result in a proven, low cost, and high efficiency solution that will allow the cost per kWH for electricity produced from the oceans¿ tides and the world¿s slow moving rivers to be competitive with hydro electricity generated at conventional dams