The winter the grid was supposed to fail, and did not

The forecasts for that winter were dark, and they were not unreasonable. Repeated strikes on generation and transmission, in a country with a cold continental climate and apartment blocks on district heating, look like the precondition for a systemic failure.

It did not happen. Supply was rationed, sometimes severely, but the system stayed up.

Three reasons, in order of importance

First, repair capacity: Ukrainian utilities had crews, spares and institutional experience, and they worked continuously. Second, imported heavy equipment — the autotransformers, breakers and switchgear released from European reserves, which turned a months-long procurement into a days-long delivery. Third, interconnection: after March 2022 the grid could import emergency power from Europe, which an isolated system cannot.

I would add a fourth that is harder to categorise. Households and businesses adapted with a speed I have not seen elsewhere — generators, batteries, shifted working hours, published schedules that everyone learned to plan around. The engineering held, and the country reorganised itself around it.