Right now is arguably the most exciting time in the nearly 200-year history of industrial electric motors. Ongoing technical advancements continue to push the limits of how efficient these motors can be, and the research and development underway in motor labs all over the world is yielding some really impressive results. Why is this important? Because electric motors use about 50 percent of all electricity produced worldwide every year, and applications that utilize these motors, such as fans, pumps and compressors, are ingrained into many aspects of our everyday lives.
As the concept of energy efficiency has gained momentum over the last few decades, more focus has been placed on making these motors as efficient as possible in order to lower their energy consumption and corresponding carbon dioxide emissions, as well as minimize the cost of running these motors over their 15 to 20 year average lifespan. After all, the electricity the motor consumes over its lifetime comprises about 96 percent of its total cost of ownership.
There are three paths that motor developers have taken to design super-efficient electric motors. One approach utilizes rare earth mineral (REM) permanent magnets, which generate strong magnetic fields allowing the motor to be several frame sizes smaller while maintaining a high power density. This technology has been around for years, but the recent volatility in the prices of some key REMs, such as neodymium and dysprosium, have made these motors so expensive, they are simply too costly for many general motor applications. For example, in 2011, the price of neodymium increased by nearly 700 percent, with dysprosium prices following a similar trajectory.
REM prices have come down dramatically since then, due partly to the massive industry consolidation in China, which accounts for more than 95 percent of all REMs produced globally every year. Another reason for the price decline is lower demand for REMs as a result of a weak global economy. Still, penetration of these types of motors into the broad market remains low due to the volatile nature of REM prices. Currently, they account for less than 0.5 percent of annual unit shipments of industrial electric motors.
The second approach to developing super-efficient motors relies on innovative designs that incorporate non REM-based magnets, such as ferrite or ceramic ones. There are several U.S.-based companies that have developed these motors, and some are starting to see growing demand from specific market sectors such as HVAC. These motor types offer a lot of potential in the hybrid and electric vehicles market, although the broad adoption of these vehicles is still years off.
The third category of super-efficient motors does not use any magnets. Instead, it utilizes some altered designs of traditional inductions motors, relying on the principles of switched or synchronous reluctance to attain the high levels of efficiency that were previously only possible with permanent magnet designs.
Although the winning technology for tomorrow’s super-efficient motor is still up in the air, one thing is certain: these machines are the future. They represent one of the fundamental pillars that humans will rely upon to dramatically reduce our energy requirements and address a root cause of climate change.