NORTH OF LYMAN, Ukraine — The race to repair this single thread of Ukraine's war-mangled electrical grid is carried out by workers in flak jackets and combat helmets alongside a rutted dirt road.
Utility workers hack and saw at leafless trees, careful to stay between plastic flagging which signifies where sappers — working some 100 yards ahead — have already swept for explosives and land mines. More workers follow with a truck and crane, stringing new power lines from one shrapnel-scarred power pole to the next.
Utility repairman Valeriy Moskat steps to the side as an armored personnel carrier roars by, loaded with soldiers headed to a nearby front.
"We do our work, they do [theirs], but we're working for the same thing," says Moskat, who works for DTEK, Ukraine's largest private energy company. "Bringing normal life back to Ukraine."
Since the end of last winter, Ukrainian utility workers and power operators have been racing to brace the country's energy system against another winter of expected Russian attacks. Transmission lines have been restrung, power plants patched, electrical substations surrounded with sandbags.
"Operationally, in terms of experience, we are much better prepared than we were last year," says Volodymyr Kudrytskyi, chief executive officer of Ukrenergo, which operates Ukraine's electrical grid. "Unfortunately, it is impossible to recover all of the assets that have been destroyed."
More than 40% of Ukraine's transmission grid was damaged or destroyed by Russian attacks last winter, according to Ukrenergo.
The attacks, launched on colder days when electrical demand was highest, targeted Ukraine's ability to generate electricity and the infrastructure required to move it. In small villages and major cities, civilians lived by candlelight, without water, heating their homes with generators and wood-burning stoves.
"They explicitly wanted to send us to the Stone Age. This is what they said," Kudrytskyi says. "They failed."
Utility workers have since restored Ukraine's electrical grid to between 90% and 95% of its prewar state, Kudrytskyi says. But with temperatures already dipping and much of Ukraine covered in snow, Russia has resumed its targeted attacks on Ukraine's energy system. And there are concerns that despite months of preparation, parts of that energy system may be more vulnerable than before.
Ukraine's electrical system is still recovering
Russia's systematic targeting of Ukraine's energy infrastructure started in October 2022, as Ukraine's armed forces were taking back territory in the country's northeast and south.
By April, more than 1,200 missiles and drones had been launched at energy-related targets alone, Kudrytskyi says, causing temporary power blackouts for millions of people.
"Every one of our objects was hit on average two times," he says, speaking at Urkenergo's headquarters in Kyiv. "Even this administrative building was hit three times by three Shahed [drones]."
A report by the United Nations Development Programme, published over the summer, estimated that Ukraine's energy system suffered more than $10 billion in damage from Russian attacks. Ukrenergo and Ukraine's Ministry of Energy don't give specific figures for damages because of security concerns, pointing instead to the UNDP report.
While most of the country's electrical grid has since been repaired — thanks in large part to funding from Western governments and private investors (Kudrytskyi says Ukrenergo received more than $1.1 billion as of late November) — some gaps remain.
Ukrainian energy companies and operators have stockpiled critical equipment to quickly replace damaged gear but some components — particularly autotransformers, which regulate voltage in transmission lines — are in short supply globally and have been hard to acquire.
Oleksandr Kharchenko, director of the Energy Industry Research Center, a Ukrainian think tank, says energy providers learned a lot from last winter's attacks.
Grid operators have learned how to better manage the system when parts of it go offline, preventing prolonged, wide-scale blackouts. They've learned how to better harden critical equipment from long-range drone and missile strikes. Coordination between Ukraine's military and energy companies has improved, providing pivotal facilities with layers of air defense systems.
But Russia has learned, too, Kharchenko says. Energy facilities are now attacked from multiple sides. And Ukraine's energy system faces a longer-term challenge in a war with no end in sight: During periods of peak demand for its now-limited number of fully operational power-generating facilities, there's barely enough electricity to meet the needs of the 37 million people who live in the country.
Ukraine's ability to make electricity has been greatly diminished
Russia's attacks on power plants and seizure of others has created what Kharchenko calls "a very unstable situation."
Ukraine's electrical generation capacity has been reduced to roughly half its pre-war state, the UNDP report found.
Russia has occupied southern Ukraine's Zaporizhzhia Nuclear Power Station, the largest nuclear power plant in Europe, since the first month of its full-scale invasion, and all six reactors have been shut down.
Oil refineries have been destroyed and hydropower plants damaged. Most recently, Russian shelling of a thermal power plant near the southeastern front in early December caused two power units to shut down and Ukraine's energy ministry to post a plea on Facebook for citizens to use electricity "wisely and economically."
Kharchenko says he expects Russia to widen Ukraine's power deficit by targeting its Soviet-era coal-fired power plants in the coming months. "We already lost nearly 70% of coal generation," he says. "That's the main problem in our energy system right now."
Most of Ukraine's coal reserves are in the eastern part of the country, where Russia has illegally annexed thousands of square miles of land and fighting continues daily. Russian troops have seized coal plants and mines.
Those that remain in Ukrainian control are old, making them difficult to repair. The most recently built, Kharchenko says, is 52 years old. And international partners have made it clear, he says, that Ukraine is unlikely to get funding to fully repair coal plants that are harmed.
All of which means it could be difficult for Ukraine to bring any damaged coal-fired power plants back online in the near- or long-term.
"Even not in this winter, but next winter and the next, next winter," Kharchenko says. "We will have even more stress connected to the deficit of generation capacity."
Efforts are underway to bring more renewable energy online
To offset some of the losses, Ukraine is trying to bring more power sources online.
In the windswept steppe of southern Ukraine, roughly 60 miles from the front lines, DTEK has expanded a wind power plant that's now providing enough electricity to power 200,000 homes.
Despite the wailing of air raid sirens and workers frequently having to scramble for bomb shelters, 13 wind turbines have been built in the Mykolaiv region since Russia's full-scale invasion, says Maksym Bogadytsya, the chief power engineer at the Tylihulska Wind Power Station.
DTEK plans to build scores more. At COP28, the United Nations climate conference in Dubai, DTEK and Vestas, a Danish wind turbine company, announced a deal to help build out the second phase of the wind power plant.
"Today, we are busy restoring not only what the occupier is destroying but also building a new energy system," DTEK CEO Maxim Timchenko said in a statement regarding the deal. An energy system, he added, that would "help strengthen the country's energy security, and enable Ukraine to become a decarbonization leader that can act as an energy hub for Europe."
Ukraine has committed to reducing its climate-warming greenhouse gas emissions by 65%, compared to 1990 levels, by 2030. The country's leadership sees decarbonizing its electrical grid as an important step toward joining the European Union, and it's aiming to capitalize on international support to reach that goal.
But in the immediate term, with electrical demand expected to surge as temperatures dip, the biggest concern for energy workers like Bogadytsya is keeping the country's lights on.
"We all know what the last winter was like," he says, standing beneath the whirring blades of the first wind turbine built after Russia's full-scale invasion. "Every megawatt is important. Every megawatt is necessary."