Marketing & Innovations

Electricity through superconductors

The inner rotor of the Hydrogenie

GE’s Power Conversion business says it has taken an important step in testing a viable way of producing large amounts of electricity from renewable resources using superconductors running at relatively high temperatures.

The company has successfully completed trials of Hydrogenie, a power generator incorporating groundbreaking technologies that enable highly efficient production of electricity in a small space. Hydrogenie makes use of superconductors instead of copper for the rotor windings on the motor, operating at 43 Kelvin or -230°C. It was tested late last year up to and well beyond its full rated load 1.7 MW spinning at 214 rpm and met expectations and design predictions.

Until recently, superconductivity could only be achieved at around 4K (-269°C). But new “high temperature superconductors” (HTS) exhibit the phenomenon at much higher temperatures. Such machines will need less complex insulation systems and less powerful cooling than used hitherto on devices such as medical MRI magnets.

“This technology is a true breakthrough,” says Martin Ingles, Hydrogenie project manager at GE Power Conversion. “It could radically improve the efficiency of equipment producing electricity from water and from wind and may also be suitable for further applications down the road.”

Latest superconductors are made by depositing a superconducting layer of ceramic onto a relatively cheap base metal. They have virtually no resistance to electrical current when cooled to very low temperatures, so windings can be made with wires having a cross section around 2 per cent of a conventional copper wire winding.

More windings can be fitted into electromagnet coils, resulting in a higher power magnet that is substantially smaller or lighter than before.