Most of the motors inside Indian fans, coolers and exhaust systems use a design that has changed very little in a century.
Induction motors are cheap and robust, and they waste a large share of the electricity they draw as heat.
The efficient alternative is the brushless direct current motor, which needs permanent magnets made from rare-earth elements.
Those magnets are largely imported, and China’s export controls on rare-earth materials have made supply a point of concern for Indian manufacturers.
That has left appliance makers choosing between cost and efficiency.
