Common consumption issues of switch mode power adapters

When electrical devices such as digital TV set-top boxes, iPads, LCD displays, and smartphone chargers are plugged into wall sockets, even if these products are idle, they are still consuming electricity if the socket switch is not turned off. Consumers usually assume that their device is turned off, but in reality, the device is only in standby mode and still consuming power.

For example, when you use the remote control to turn off the LCD TV, the power inside the LCD TV is still on and supplying power to the remote control receiver, so the LCD TV is still consuming electricity in standby or sleep mode. Although the power consumption of the remote control receiver is minimal (about 0.1W), the switch power supply inside the LCD TV is still in standby mode, which consumes power and often wastes a few watts of power. This is what we call standby power consumption.

What is the no-load power consumption of a switching power supply?

The idle power consumption of switch mode power supplies is a subclass of standby power consumption. Idle power refers to the electrical energy used by a switching power supply when disconnected from a load device and not performing any functions. For example, a mobile phone charger plugged into a wall socket, although not connected to the phone, still consumes power. At present, the energy efficiency of mobile phone chargers is mostly at V and VI levels, and even when disconnected from the phone, they can still consume 0.5 W of power.

Which devices use standby power?

All electronic devices with external power adapters, chargers, and switch power supplies require standby power. Strictly speaking, all electronic products need to be plugged into wall sockets, such as televisions, iPads, air conditioners, washing machines, mobile phone chargers, lighting fixtures, cordless phones, refrigerators, cable TV set-top boxes, satellite TV decoders, radios, computers, printers, monitors, fax machines, copiers, modems, audio amplifiers, industrial control devices, and motor control devices, etc.

Why is standby power consumption a problem that needs to be solved?

Although the standby loss of a single device may seem insignificant, the problem quickly becomes apparent when you multiply the number of homes by the number of appliances in the home and the amount of standby consumption per appliance. According to the International Energy Agency, 5-15% of global household appliance consumption is generated in standby mode. In the United States, the cost per watt of electricity is approximately $1 to $1.5 per year. The Lawrence Berkeley National Laboratory estimates that in the annual electricity bill of American households, standby losses will exceed 5 billion. According to a report from the US Department of Energy, the standby electricity used in the United States each year is equivalent to the electricity generated by 26 average sized power plants!

With the popularization of household appliances and the increase of new devices with electronic controls and multiple functions, this problem will also become increasingly prominent.

How to reduce standby power consumption?

Up to 90% of standby power consumption is caused by low conversion efficiency power supply designs. The Lawrence Berkeley National Laboratory in the United States estimates that if new technology devices are adopted, standby power consumption may be reduced by 75%, and almost all standby functions can be performed using devices with a total standby power consumption of 0.3 watts or even lower. To achieve this goal, improved switching power technology and design can be adopted, that is, using more intelligent switching power adapters to replace inefficient linear power adapters; At present, it is difficult to see linear power adapters in our living surroundings; Linear power adapters have gradually been phased out.