What happens when a the electrical voltage is low?

Appliances at home have designated voltage e.g. 220 V or 110 V. When the voltage is dropped, the appliances try to run at their designated power in kW as usual. To keep the power same, current is increased (P = VI). This increase in current can burn the most delicate part of the appliances if the low voltage is experienced persistently.

A drop in supply voltage results in a drop in the power of appliances. For fixed-resistance devices, a 10% drop in voltage results in approx, 18% drop in power.