What is happening to Ukrainian energy system and how decentralization can help

Previously, electricity generation in Ukraine was distributed approximately as follows: 50% at nuclear power plants, 30% at thermal power plants, and a little more than 10% at hydroelectric power plants. Accordingly, less than 10% was generated thanks to renewable energy sources (RES). However, this changed with the beginning of Russia's full-scale invasion and with the shelling of energy infrastructure.

One of the strongest blows to the Ukrainian energy sector was in Melitopol when the Russians occupied the Zaporizhzhia nuclear power plant and turned off the last unit in September 2022. Thus, Ukrainian nuclear power generation lost almost half its capacity, approximately 6 GW, from the 13.8 GW it previously produced. At the same time, the Russians are not shelling other nuclear energy facilities at all.

But the biggest losses are in heat generation. Some of the Ukrainian thermal power plants are under occupation, and others have been damaged or destroyed by Russian shelling. So, for example, Centrenergo, a major electric and thermal energy-producing company in central Ukraine and eastern Ukraine, lost absolutely all generation due to the destruction of the Trypilska and Zmiivska thermal power plants and the occupation of Vuhlehirska power station.

"We do not have a single intact thermal power plant on the territory under the control of the government of Ukraine. Large system stations such as Burshtyn, Ladyzhyn, Prydniprovska, or Kryvyi Rih have been shelled many times and have very severe damage," says Oleksandr Vizir, the head of the NGO Association of Energy Efficiency and Energy Saving.

According to Ukraine's Prime Minister Denys Shmyhal, only 27% of TPPs remain in working order, and 42 power units have been completely destroyed.

There were also losses in hydropower; in particular, the Russians destroyed the Kakhovka HPP. However, according to Vizir, the detonation caused more damage to the environment than to energy since the station did not have large capacities. The shelling of the Dnipro HPP on March 22, 2024, was a much more significant blow. Then, the most powerful hydroelectric plant lost over 40% of its generation.

Ukrainian generation lost a large part of the wind turbines in the occupied parts of Zaporizhzhia and Kherson regions. Solar power plants also suffer from shelling, which are easy targets due to the large areas they occupy.

This leads to a shortage of electricity in Ukraine. As a result, blackout schedules have returned to Ukrainians' lives. Although there is less talk about a total blackout now, the situation is still critical. Another winter is coming, and this time, the problem with electricity will be much more difficult than in 2023. 

According to the "optimistic" forecasts of Serhii Kovalenko, YASNO energy supplier general director, Ukrainians will only have six to seven hours of electricity daily in wintertime. At the same time, some forecasts say that, in the worst-case scenario, Ukrainians may have to spend 20 hours without electricity and heating. However, the Ministry of Energy believes it is still too early to discuss the duration of the winter blackouts.

"Today, it is still too early to talk about any hourly figures regarding restrictions (in electricity — ed.) in winter. All these attacks cause additional problems for the power system, but it is too early to say we will have long blackouts in the winter. However, of course, the situation can change daily and after every attack," Svitlana Grynchuk, deputy minister of energy, said.

By shelling and destroying thermal and hydro generation, the Russians are not only depriving Ukrainians of this source of energy, but to a certain extent, they are making it more challenging to use nuclear energy and renewable sources.

Generation works according to the principle that exactly as much electricity is produced as it is consumed every moment. If more than necessary is produced, some generation facilities are turned off. Conversely, if there is not enough electricity, some consumers are turned off to balance the electricity system.

At the same time, the graph of electricity consumption is not a straight line but rather waves that show constant decreases and increases in consumption throughout the day. That is, the generation must be such that it can change its capacity in accordance with the needs of the population at any time.

At this stage, the problems of using nuclear power plants begin since they belong to the basic generation. This means such plants constantly produce the same amount of energy, which cannot be quickly increased or decreased.

For example, Ukraine has one 1 GW nuclear power plant, so consumption at any moment should be 1 GW per hour. If, at some point in time, consumption rises to 2 GW per hour, the controller will disconnect 1 GW of consumers. If consumption is 0.5 GW at some point in time, the controller will shut down the nuclear power plant because it is physically impossible to reduce the generation.

That is why nuclear power plants usually produce electricity 20-30% less than the minimum daily consumption to avoid a situation where one of the nuclear units has to be shut down because, according to Vizir, "it is very expensive and not very economical."

The electricity we use consists of basic generation (NPP) and shunting (HPP, TPP), which allows us to adapt to consumers. The Russians inflicted significant damage on the shunting one. Therefore, planned or emergency blackouts are implemented when there is not enough electricity from nuclear power plants and the remains of hydroelectric power stations and thermal power plants.

We need to restore electricity generation now, but it is also essential to understand how to do it efficiently. Rebuilding, as it was before, is completely impractical because Ukraine's energy system was designed quite a long time ago and does not meet modern needs and challenges.

The current centralized generation has several disadvantages. One of the biggest is the loss of electricity during transportation, which causes every tenth kW in the network to be lost. At the same time, it is extremely difficult to protect the objects of the Ukrainian energy system from enemy attacks since it is impossible to hide a giant TPP, HPP, or nuclear power plant from missile strikes.

Instead, it is possible to develop decentralized generation by restoring the electrical system. This assumes that some of the electricity consumers will also become its producers. For example, a company can install gas installations, or a community can install solar panels on the roof of one of the schools. Then, they will be able to partially provide themselves with electricity and relieve the general energy system.

Rubryka visited such an enterprise and will share how installing a solar power plant affected its energy independence.

Here, several workshops manufacture packaging equipment from scratch. The process starts with producing the smallest parts, which are less than a centimeter in size, and ends with specialists assembling fully finished devices.

"We manufacture packaging equipment our client uses to package their products. It can be seeds, sugar, salt, etc. Everything that can be wrapped in film is packed with tools like ours," says Viktor Dehtyar, director of the Packaging Technologies enterprise.

Such equipment is produced here for small businesses or farmers and for big Ukrainian companies, whose products can be found in every supermarket. This company also works for export. For example, one of the devices in the warehouse is being prepared for shipment to Poland.

For such an enterprise to work, about 200 kW of electricity per hour is needed—that's like 1000 refrigerators working at the same time. Now, thanks to the solar power plant installed on the roof of three workshops, the production is able to support itself. Under favorable conditions, more electricity is produced than is needed, and the surplus is sold to the general network.

The first solar panels were installed here almost six years ago, long before the first blackouts in Ukraine started. First, a 30 kW plant was established to test its efficiency. After some time, they began to scale up and have now reached the maximum allowed, producing approximately 200 kW per hour. The director of the enterprise explains it is much more profitable to produce electricity yourself than to buy it from the state.

"When I started, electricity was less than one cent per kWh, which was already profitable — the solar panels paid off in about five years. Now, electricity prices are increasing, while panels, on the contrary, are getting cheaper every year. Now they pay off much faster, in two years," he explains.

Also, according to the production director, the costs of maintaining a solar power plant are almost imperceptible.

Such a solution benefits not only the enterprise, reducing its costs, but also the state in general. In conditions of a generation deficit, the enterprise unloads the network because it does not consume electricity from it, and sometimes, on the contrary, it can also give the surplus of its generation. Accordingly, this amount of electricity can be redirected to other consumers.

At the same time, such a solution has certain limitations. First and foremost, solar power plants need the sun to operate, and this is a rather unpredictable factor. Today, in clear weather, the enterprise can provide for itself independently, but tomorrow, clouds will appear, and the capacity will only be enough to partially provide for itself.

It is also necessary to adjust production to daylight. For example, Packaging Technologies works from 10:00 a.m. to 5:00 p.m., exactly when the sun is there. At the same time, the capacities of solar power panels decrease in winter to 20-30% of those in summer as the daylight hours decrease.

Another problem is that most solar power plants require electricity from the grid to operate. This means the solar panels are out when there is no electricity and the business is still without electricity.

However, several solutions can help eliminate this problem. The first, quite simple and familiar to most Ukrainians, is to start the generator. Then, instead of electricity from the network, this generator will provide it, and the solar panels will be able to resume work and further provide for the enterprise.

The next solution is to install more modern hybrid solar systems that can operate independently and have a switching time of only ten milliseconds, much less than manually switching to generators. This can be quite important for some businesses, as prolonged downtime can cause equipment to malfunction.

Vizir offers another solution. It requires systematization and the state's interest in the person of Ukrenergo, the dispatcher who decides which of the consumers should be turned off due to an electricity shortage. They could not disconnect businesses that are partially or fully self-sufficient in electricity because they are offloading the grid. Why turn off a consumer who takes the minimum to support himself, and under favorable conditions also gives out excess electricity?

At the same time, such a solution could be an additional incentive for Ukrainian businesses to install SPPs or other sources of electricity on their premises. In this way, it will be possible to relieve the load on the Ukrainian power grid and at least partially compensate for the destroyed generation. This would also be the first step in the development of decentralized generation.

According to the changes to Ukrainian legislation in the field of energy introduced on June 30, 2023, this generation model is called an "active consumer." This means that the consumer not only takes electricity from the network but can also give it back or at least partially provide for themself.

An "active consumer" can be both a natural person and a legal entity. This allows individual communities, private enterprises, or condominiums to independently produce electricity. To acquire this status, at least one of the following requirements must be met:

• consume and produce electricity;
• carry out electricity storage activities;
• sell surplus electricity produced;
• participate in energy efficiency and demand management measures in accordance with the requirements of the law.

The production and sale of electricity mustn't be a professional or economic activity.

Next, the "active consumer" can sign an electricity purchase and sale agreement with their supplier. This agreement will become an addition to the contract on the supply of electricity to the consumer. This will make it possible to buy electricity when there is not enough of one's own capacity and sell the excess to the grid.

At the same time, the new legislation does not limit the "active consumer" and makes it possible to sell excess electricity to other consumers.

The spread of the "active consumer" model will make the Ukrainian network more decentralized and, therefore, more secure and energy efficient. Every business, community, or condominium that installs generating units will become more energy-independent and experience blackouts less painfully.