Berkeley Lab

Archives: Newest Members to the Standby Club: White Goods

Many common household appliances are becoming “smarter” with the ability to receive and send signals, sense substances such as dirt or frost, and to automatically turn themselves on or off in response to pre-programmed commands or other stimuli. The DC components that make these functions possible consume power even when the appliance is not on or “running.”

In addition, these components require that the 110 volts available in U.S. homes be stepped down to between 2 and 20 volts by a transformer. In many electronic devices, such as answering machines or battery chargers, this transformer is found in the little black box that plugs into the wall. (The heat you feel coming from these power supplies is actually leaking electricity being converted into thermal energy.) In white goods, such as those shown below, the power supply and transformer are usually hidden away inside the appliance.

Refrigerator (left) and Dishwasher (right)

Although you can’t see them, this refrigerator and dishwasher have leaky transformers inside, which are needed to supply the proper voltage to the sensors and displays.

Range (left) and Microwave oven (right)

The electronic touchpad controls on the range and microwave oven shown here tend to be easier to clean than their mechanical counterparts, but must be powered continuously to sense when the “buttons” are being depressed.

Washers (left) and Japanese toilet (right)

The kitchen isn’t the only place you’ll find standby power. Electronic controls can be found on washers, dryers, hot water heaters, furnaces — even toilet seats, such as the Japanese model shown here.

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