Why the voltage “surges” during application of power shutdown schedules? – DTEK Kyiv Regional Grids answers

Thermal power generation20 February 2026

During the period of stabilization power shutdowns application, voltage surges in homes may occur after electricity restoration. DTEK Kyiv Regional Grids specialists explain why it happens and give advices how to reduce the risks.

Voltage surges during application of stabilization shutdown schedules most often occur immediately after restoration of power supply. The main cause is a sudden increase in load on the grid due to the simultaneous turning on of the large number of electrical appliances.

Under conditions of sufficient amount of electricity, power consumption is carried out evenly throughout the day. During application of power shutdown schedules, the situation changes: when electricity appears, all residents almost simultaneously turn on their boilers, heaters, electric stoves and other powerful appliances. Grids and wires in the houses are working in the conditions of increased load, therefore, the voltage decreases temporarily. Usually, it becomes stable within 1–1.5 hours, when consumption becomes balanced. The situation is additionally complicated by the frost that significantly increases overall electricity consumption.

The second major reason is regular damage of power facilities by the enemy. This significantly affects the stability of the voltage levels in the Ukrainian energy system in general. When energy workers are working on restorations after the attacks, backup lines are often used. This is why the distance to the power source and the load on the grid increases several times. This may cause either a decrease or an increase in voltage, especially during the switchover.

Another frequent cause of drops and surges is damage or breakdown of the neutral wire in the building, which is used by the grid for reconnection to the power source. In this case, an uneven load occurs between phases: voltage on one phase may go down to 150 V, while on the other ‒ go up to 270–300 V and more. This is an emergency situation that threatens household appliances and requires immediate specialists’ intervention.

What should residents do:

After restoration of power supply, turn on powerful electric appliances in turns, and not all at once ‒ this will reduce the load on the grid.

In the majority of cases, the load becomes stable within 1–1.5 hours. If power surges last longer, ask condominium association, housing cooperative or building manager to inspect internal networks.

If the internal networks are in a working order, the manager submits a request to the Distribution System Operator. After that, DTEK Kyiv Regional Grisd specialists inspect external lines and eliminate causes of failures.