Rare Earths in Clean Energy Technologies
Rare earths play a key role in the expected growth of many emerging clean energy technologies. The next generation of wind and hydro power turbines, batteries, motors to power electric vehicles, motors for electric power steering, magnetic refrigeration, energy efficient appliance motors, and fuel cells are examples of applications that are expected to contribute significantly to the quest for energy independence. Each one of these uses helps us decrease greenhouse gas emissions, saves fuel, and improves the management of energy throughout the supply chain.
The demand for rare earths in wind power generation is an area of significant potential growth. The next generation of wind turbines utilize direct drive turbines fueled by highly efficient rare earth permanent magnet generators (PMGs). These designs eliminate the gearboxes that reduce efficiency and that are often a source of mechanical failure. In addition to improved efficiency, the new direct drive turbines provide major improvements in reliability, a factor that is particularly important in off-shore wind power generation. PMGs, which utilize the high powered neodymium-iron-boron magnets, require a significant amount of rare earths: a 3 megawatt turbine uses roughly 1 metric ton of rare earths.
One of the most common clean energy applications of Rare Earth elements is their use in energy efficient lighting. Rare earth phosphors are applied to the insides of the bulbs and generate light when energy is applied. These compact fluorescent lamps (CFL’s) are replacing the standard incandescent light bulbs at a rapid rate.
Incandescent bulbs waste 95% of their energy and convert only 5% to actual light. Contrast this to the CFL which converts 25% of input energy to visible light via its rare earth phosphor coating. This efficiency results in much lower lamp temperatures, significantly longer life (estimated at 6 to 10 times as long), and less total energy consumed, directly reducing greenhouse gas emissions. ENERGYSTAR reports that if every home in America replaced just one incandescent light bulb with a qualified CFL then in one year that action would save enough energy to light more than 3 million homes. This would prevent the release of greenhouse gas emissions equal to that of about 800,000 cars. Countries around the globe are mandating the phase out of incandescent bulbs. Australia led the way by announcing all bulbs must be replaced with CFLs by 2010. The U.S. passed an energy bill that bans incandescent bulbs by 2014. It is estimated that rare earth consumption in this application is growing about 15-20% per year meaning additional supply will be necessary to support this growth. More information can be found on the ENERGYSTAR website.