TechTalk: PMG future must ensure ethical supply chain

WORLDWIDE: In late 2010 I attended a public discussion on the role and risks of strategic materials required for our future energy supply, in particular relating to nuclear power.

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The panel leading the debate included a nuclear-engineering professor and an industrial ecologist. The nuclear expert was in a winning mood, proclaiming an inevitable nuclear-power renaissance. He enthused about next-generation safe and ultimately fail-safe reactor designs being developed for rapid worldwide dissemination.

The ecologist offered an overview of traditional strategic materials such as copper, and "modern" ones, including lithium, neodymium and dysprosium. He talked about possible future shortages in different materials and how this could affect life. Copper availability is crucial in the global efforts in increasing wind and other renewables generation, which requires major electrical network infrastructure expansion.

He emphasised China's global market dominance in rare earths, with specific elements needed for high-tech usage in telecommunication equipment. Neodymium and dysprosium-based alloys are base materials for powerful permanent magnets used in many different devices from halogen lights and smartphones to permanent-magnet generators (PMGs) in wind turbines and electric motors for hybrid and electric vehicles.

The ecologist claimed that the future of wind power was threatened by the industry's heavy reliance on PMGs, believing this to be a standard turbine fitting. I explained this was incorrect and that conventional generators, including induction and doubly-fed induction generators, dominate the wind industry.

Overtaken by events

Japan's Fukushima nuclear disaster happened only months later and turned nuclear renaissance hopes into a nuclear nightmare.. It made Germany decide to close several nuclear plants, marking the start of a radical transition towards renewable energy.

During roughly the same period, China imposed stringent quotas on rare-earth and magnet material exports, prompting a price hike in early 2011. This led to a rethink by the wind industry on the future of direct-drive PMG and speeded up efforts to develop medium-speed systems with much-reduced demand for magnets.

Today's rare-earth situation is different. New mines are being opened outside China to help meet demand and reduce price fluctuation risks and single-market dependency. In parallel, materials made by combining specific elements could start to offer an alternative to "traditional" rare earths, and international recycling efforts also look increasingly promising. Initial industry fears for continuous high price levels and limited availability seem to have largely faded away.

Negative publicity

One remaining threat to rare-earths use in wind turbines is the ongoing negative publicity surrounding unhealthy and environmentally damaging mining practices in China. In 2011 the German media linked neodymium-mining with wind-turbine generator use, calling it "the dirty side of a clean wind industry". The issue triggered much public debate, and among the accused was major German manufacturer Enercon, even though the company makes turbines incorporating "classic" electrically excited direct-drive generators, a principle that does not incorporate permanent magnets.

More recently an anti-wind group published an "updated" 2011 article offering a detailed account of neodymium-mining practices in China's Baotou region in Inner Mongolia. It describes how neodymium fraction is separated from radioactive uranium and thorium fractions. The latter are than dumped in lakes and open basins, together with poisonous chemicals, causing disease and premature death through heavy pollution of soil, water and air, affecting humans, flora and fauna.

The authors asked whether their findings would mean an end to wind power. This sounds ridiculous, because permanent magnet technology is far too elegant and valuable to be wasted. But the global wind industry must address two major issues. One is to actively promote clean, safe mining practices everywhere. The other is to communicate to both wind turbine clients and the general public the great value of permanent magnet technology and the wind industry's determination to link their advanced clean-power generating hardware with sound rare-earths mining and processing practices.

Failure to act gives anti-wind groups a powerful weapon with which to attack wind power for offering false promises. Most importantly, wind power only qualifies as clean and sustainable when the entire supply chain respects people and their environment.

Eize de Vries is Windpower Monthly's technology and market trends consultant

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