一些电子设备既使在不使用的情况下,也会继续耗电。例如与电视机连接的有线电视机顶盒、盒式录像机和卫星接收器等即使在关闭电视机后,这些设备仍处于接通状态。蜂窝式电话充电器只要插入墙上的插座就耗电。这些设备中的开关电源(SMPS)总是处于备用状态,每台设备耗电5～10W。据备国联邦环境局称,这些备用电源的耗电量占电费的10％。 Some electronic devices continue to consume power even when not in use. For example, cable set-top boxes, video cassette recorders and satellite receivers connected to a television set are still on even after the television is turned off. Cellular phone chargers simply drain into the wall outlet. The switching power supply (SMPS) in these devices is always on standby, consuming 5-10 W each. According to the preparation of the Federal Environment Agency, these backup power supplies account for 10% of their electricity bills.