In the Summer 2009 edition of Magnetics Business & Technology, Tony Morcos of ACM Magnetics wrote an excellent article that dissects the growing conventional wisdom that near- and medium-term future growth in wind turbine production, will lead to vast shortages of neodymium-based [Nd-Fe-B] permanent magnets.
Tony points out that permanent magnets are just one option for electrical generators. Numerous considerations have to be taken into account by the machine designer in his or her bid to maximize efficiency of energy conversion, while minimizing cost. He points out that any theoretical reduction in supply of permanent magnet materials would be self-limiting, because of the variety of topologies and configurations that can be used with or without permanent magnets. New designs that don’t use permanent magnets will be developed in parallel to those that do.
Tony then goes on to explain that Nd-Fe-B might not, in fact, be the most cost effective permanent magnet material to use in wind turbines, and his explanation makes a lot of sense – read the article to see which material he suggests as an alternative.
Tony concludes by asserting that all suppliers of the various elements of wind turbines should see increased demand for their products – suppliers of the copper wire for windings and cabling, power electronics vendors and those who provide permanent magnets – but without significantly affecting the ultimate price of these items.
I heartily recommend this article, as it gives a fresh perspective to the whole “magnets for turbines” discussion, and highlights the growing school of thought that permanent magnets are not the “be-all and end-all” for wind turbine generators. It can be found on page 26 of the Summer 2009 edition of the magazine.