Why leaving chargers plugged in could quietly raise your power bill

Phone and laptop chargers are often left plugged in around the house, even when not in use. But Glen Farivar, a lecturer in power electronics at the University of Melbourne, says this habit leads to what is known as "vampire power", a continuous, low-level energy draw that occurs even when a device is not connected.

This standby power keeps internal circuits running and releases excess energy as heat.

While the consumption of a single charger is minimal, the total from all devices across a household can add up over time. Farivar told The Conversation that other electronics like TVs also draw standby power when idle.

Devices plugged in to power source. Photo from Unsplash

The U.S. Department of Energy estimates that unplugging unused chargers and electronics can save the average household up to $100 annually.

Beyond energy waste, leaving chargers plugged in may increase the risk of fire, especially in older or low-quality models. Experts recommend unplugging chargers at night or when leaving home, as overheating can occur at any time, as reported by The Star.

Chargers left connected are also exposed to regular electrical fluctuations, which may wear them out faster and reduce their efficiency. Power surges during storms or outages can even trigger short circuits.

While most modern chargers are safe and use little standby power, they should still be unplugged when possible. If a charger becomes unusually warm, emits noise, or shows signs of damage, it should be replaced immediately, and not left plugged in.