For the past week and a half, Russia has been attacking Ukraine with rockets and drones every day.
Projectiles also hit the capital Kyiv several times, killing dozens of civilians across the country.
With this new wave of attacks, Moscow is particularly targeting the neighboring country's critical infrastructure.
Some questions and answers on the situation in Ukraine:
How big is the damage in Ukraine?
President Volodymyr Zelenskyy said that around 40 percent of Ukraine's power plants had already been damaged.
Again and again parts of the country are without electricity, sometimes also without water and without gas for heating.
With winter approaching, this is of particular concern to people in the war-torn country.
The export of Ukrainian electricity to Europe - including Poland - was stopped days ago because of the Russian attacks and the resulting shortages in their own country.
"Russia is committing energy terror against Ukraine," according to the responsible ministry in Kyiv.
What are the concrete effects for the people of Ukraine?
In order to prevent major bottlenecks, the Ukrainians have been called upon to save energy for days.
If possible, power guzzlers such as ovens and microwaves should not be switched on at all.
In addition, nationwide power cuts in private households began on Thursday.
The utility Ukrenerho had previously announced that between 7:00 a.m. and 10:00 p.m. local time, the power should be switched off in each area for up to four hours at different times.
"This is a forced step.
But we are all working together on this front,” said Deputy Head of the Office of the President Kyrylo Tymoshenko.
The Ukrainians were asked to charge their mobile phones and power banks in good time and to have flashlights, batteries and water ready.
"We do not rule out that we will ask for your help more often with the onset of cold," said Ukrenerho.
In Kyiv, the heating season has now opened in view of the sharp drop in temperatures - also so that the citizens do not use the precious electricity for private heating devices.
Local public transport was also badly affected by the austerity measure.
Only half of the electric buses should drive in the Poltava region, and none at all in Ternopil.
In Kyiv, only 21 of the 38 e-bus lines were used regularly, and some were replaced by vehicles powered by petrol.
Restaurants and bars were also asked to switch off neon signs and electronic decorations.
What is the background of the Russian attacks?
Kremlin chief Vladimir Putin ordered renewed massive attacks after an explosion at the Crimean Bridge on October 8.
The structure connects Russia and the Black Sea peninsula annexed in 2014 - and is both strategically and symbolically important for Moscow.
Putin blamed the Ukrainian secret service SBU for the momentous detonation and spoke of a "terrorist attack" against Russian territory.
However, the SBU has never confirmed involvement.
According to the Kremlin, the current Russian attacks are retaliation for the Crimean Bridge incident and for other attacks on objects of critical Russian infrastructure that Moscow accuses Kyiv of.
However, many international military observers assume that Russia's current violent wave of attacks on Ukraine must have been planned for the long term.
Will the EU help Ukraine?
Internationally, the targeted shelling of energy plants in an already war-torn country caused horror.
The European Union has pledged support to Ukraine.
According to Energy Commissioner Kadri Simson, the EU, together with the energy sector, is providing funds and equipment to repair Ukraine's infrastructure - for example for damaged grids or thermal power plants.
In March, the Ukrainian electricity grid - like that of the neighboring Republic of Moldova - was connected to that of the EU.
As a result, EU states can supply Ukraine with electricity at short notice.
Kyiv should also be allowed to participate in the EU's joint gas purchases.
The system for this should be functional from next spring and enable lower prices through the concentrated market power of the Union.