CERN Accelerating science

  "Green Magnets" to save energy in accelerators
    by Livia Lapadatescu (CERN), Thomas Hind (CERN)

 Fig 1: Green Magnets developed at Danfysik
 Image credit: Danfysik

A partnership of universities and industry have produced “Green Magnets” which give more than 95% electrical efficiency savings. The “Green Magnets” technology could be used to replace non-superconducting accelerator electromagnets.

The idea for the magnets, which work by using very strong permanent magnetic materials based on rare earth minerals and shaping them in such a way to provide the desired magnetic field, originated at the International Climate Summit in Copenhagen in 2009. The partners expressed a desire to save energy and cut carbon emissions in accelerators and identified magnets as their primary power consumer. Breaking their set target of reducing power consumption by 75%, they managed to achieve a 95% cut in energy use in the magnets, as well as removing the need for water cooling infrastructure, heavy cabling and large power supplies.

The magnets were developed through a project run by five partners from academia and industry (Aarhus University, Aalborg University, Aarhus School of Engineering, Sintex A/S and Danfysik A/S). With financial support coming from Danish Advanced Technology Foundation the consortium is  able to replace non-superconducting electromagnets of up to 1 Tesla which need not more than +/- 25% field variation during operation.

Having overcome various technical challenges, such as temperature stability and radiation resistance, what remains now is the challenge of increasing the focus of labs on energy consumption and sustainability, in addition to successfully marketing the need for more energy efficient magnets such as the Green Magnets.