Officials are concerned that life will quickly become unsustainable for millions if supplies cannot be kept for at least four hours a day. Some families in Kyiv are already facing outages of up to 20 hours, and some people privately warn that point is close.
Ukrainians are living through lengthening blackouts after Russian strikes knocked power plants and grid lines offline, the BBC reported.
Nationwide, hundreds of thousands of Ukrainians have gone without power in recent weeks. The cuts were introduced earlier this year than last winter, and they are already lasting longer.
A ballistic missile strike left one of the country's largest power stations completely offline, according to the BBC. The plant, which reporters were asked not to name for security reasons, has been reduced to twisted metal and broken pipes, its turbines buried in rubble.
Volodymyr Kovalenko, who followed his parents into the work and has been at the site for 25 years, told the BBC the damage was heartbreaking, though he was confident it could be repaired.
A 39-year-old who has worked at the plant for half his life was dwarfed by the ruins and daunted by the task of rebuilding. When the air raid siren sounds, workers have to get out as quickly as possible.
Rebuilding the damaged station would take at least until next summer, the BBC reported, because crews under sustained attack were limited to only one or two productive hours a day.
With the latest threat over, a team on the edge of the site returned to reinstating the lines that feed the national grid. Kovalenko echoed a sense of mission about trying to keep the lights on.
Ukraine has responded by striking Russian oil refineries.
In parts of the country, parents are struggling to keep an ordinary family life going on only a few hours of power a day.
In Kyiv, a single parent in a seventh-floor flat is trying to feed two children and see that they do their homework. The lift does not work, and the water stops because electricity is needed to pump it up to the flat.
"There's no light, no water, no heat, no electricity,"one account of the outages recorded. Daryna said:"You have a big city around but you see nothing because there's no light.".
Homes like Daryna's are darker and colder as the cuts stretch on. Many people are choosing to leave the capital, or Ukraine altogether, to avoid months of bitter cold.