An electrical circuit for use with plural, low voltage loads such as a string of Christmas lights is disclosed comprising groups of lights placed electrically in a series circuit but the lights within each group are in parallel, preferably with a semiconductor device in parallel with each group to limit current and voltage in the group. By suitable choice of bulb, group size and number of groups, a light string can be fashioned that that uses about one third the power with much less heat production and without loss of brightness. The semiconductor device can consist essentially of diodes such as two silica diodes on either side of a Zener diode, or a custom bipolar device.