Energy saving upgrade without sacrifice Halogen PAR lamps reduce energy consumption without sacrificing the qualities of a traditional PAR lamp. They uniquely produce light more efficiently. They work with dimmer switches and are available in the familiar PAR20, PAR30S, PAR30L, and PAR38 shapes. Use them in existing fixtures just as you would standard halogen PAR lamps. A bright, energy saving alternative to standard halogen PAR lamps.