Tech Insights

Polarizing: Can Magnet-Free Turbines Produce Wind?

May 21, 2024 by Liam Critchley

A wind developer believes its technology can loosen China's tight grip on rare earth magnets.

Offshore wind turbines rely on rare earth permanent magnets (RE-PM). However, China controls 90% of RE-PMs, so the market monopoly creates potential supply bottlenecks, shortages, and price fluctuations (including price gouges) in today's tense geopolitical climate. 

Hyper Tech Research, Inc. may have a solution to free the supply chain from RE-PM constraints. Their superconducting wire could eliminate the need for magnetics and lead to more efficient and affordable offshore wind turbines. 

 

Wind turbine mast interior.

Wind turbine mast interior. Image used courtesy of Adobe Stock

 

Hyper Tech’s Superconducting Cable 

Superconducting materials are highly sought after in electronic applications because they have zero resistance, which allows electrons to flow without any impedance. 

Theoretically, superconductors are the ideal material for energy and electronics applications, but they have to be cooled to ultra-low temperatures to work, which sometimes makes them impractical. However, their benefits keep driving superconducting research to new heights.

The Hyper Tech Research team has created a superconducting cable made of magnesium diboride (MgB2) microfilaments that needs cooling to -390°F to work. While still very cold, this temperature is much warmer than the superconducting materials used in MRI magnets at -443°F. The superconductors are also cheaper to cool since liquid hydrogen can be used rather than liquid helium or liquid nitrogen.

 

Liquid hydrogen operates at low temperatures.

Liquid hydrogen operates at low temperatures. Image used courtesy of Wikimedia Commons

 

Using semiconductor wires enables more electricity to be conducted with less material. The cables are intended to construct smaller and lighter direct-drive generators for wind turbines, stopping the reliance on RE-PMs, including rare and expensive permanent magnet materials such as neodymium.

The team’s superconducting generators could lead to bigger wind turbines producing more energy without taking up space. This would be possible with superconducting generators due to the efficiency gains from the superconductors, which could power larger systems and lead to a more cost-effective wind turbine and energy generation.

 

Practicality: Always a Challenge for Superconductors

Many researchers are interested in superconducting materials, but no one has yet found the holy grail of room-temperature superconductors. In 2023, Korean scientists claimed in a preprint paper that they discovered a room-temperature semiconductor called LK99. However, the research community quickly debunked the claim after they failed to replicate the results. It turned out the LK99 material is diamagnetic and can levitate in high magnetic fields. Superconductors levitate over magnets, which led the Korean researchers to incorrectly conclude the material was a superconductor.

There’s no denying that superconductors—if utilized effectively—have the potential to transform the grid and almost all electronic applications due to their lack of electrical resistance. 

However, given their cooling needs, many will question whether superconductors are the most practical solution for large-scale operations. Granted, the Hyper Tech team has found a cheaper option in liquid hydrogen for cooling the superconductors. However, since many wind turbines are in remote and offshore locations, how often will the liquid hydrogen need replacing, and who will do it? In modern-day MRI machines, liquid helium must only be replaced every few years. The team has not addressed the practicalities of more frequent liquid changes.

Many questions remain regarding this development, but it’s exciting to witness some interesting use cases of superconductors in the renewable energy field.

 

The CABLE Prize for Conductor Solutions

Hyper Tech’s superconducting cable from Hyper Tech Research has reached the final stages in the Department of Energy’s competition for Conductivity-Enhanced Materials for Affordable, Breakthrough Leapfrog Electric and Thermal Applications (CABLE). The winners will receive $500,000 to develop their materials further.