After decades of hiatus, the project of the hot pipeline from the Dukovany Nuclear Power Plant to Brno has been restarted. The original plans from the 1980s were revived in the context of rising energy prices and efforts to reduce dependence on natural gas. The cost of building the hot pipeline is estimated at CZK 19 billion, a projected expenditure in 2030.
The preparatory phase, including design and land purchases, should be completed by 2027, with construction starting a year later. ČEZ will prepare a heat exchanger that will allow the power output of the Dukovany nuclear power plant to be exported to the edge of the plant, and Teplárny Brno will invest in a 42-kilometer-long hot water pipeline. "Customers who are currently connected to gas-fired heating plants in Brno should have their first supply of heat exported from Dukovany in the season between 2030 and 2031. This strategically important project will significantly change the way Brno is supplied with heat," says Petr Fajmon, CEO of Teplárny Brno, in an interview.
When was the idea of building a hot water network from the Dukovany Nuclear Power Plant to Brno born?
The idea originated in the 1980s. The project was conceived in such a way that when the Dukovany NPP was built, some of the heat would be taken out of the cogeneration and water would be brought to Brno through a relatively long hot water pipeline. Everything was included in the zoning plans, preparations were even started, and the appropriate sections and tunnels were built. The project was alternately started and then stopped. I remember that when I started working at Teplárny Brno in 2011, representatives of ČEZ came to see me to ask if the project would be reopened. In the meantime, however, natural gas prices had fallen a lot, the price was around EUR 20 per megawatt-hour, and the planned project was not economically viable at that time.
The last impetus that got the idea of the pipeline going again was the energy crisis that followed the covid when energy prices skyrocketed. The mayor revived the project again, and we started talking realistically about what we needed to do in terms of heat supply to reduce our dependence on natural gas.
The primary base of the Brno Heating Plant is based on natural gas, which we burn eighty percent. The remaining roughly 20 percent of our heat is produced from municipal waste. We are one of the largest consumers of natural gas in the Czech Republic. We had purchased gas in advance, yet at the time of the energy crisis, its prices soared to five to six times, which we could not let happen without an adequate response. The situation has calmed down since then, we have already reduced our prices twice, but we want to be energy-independent, which is why we have returned to the hot pipeline project.
Two years ago we signed a memorandum with ČEZ, a year ago we signed a cooperation agreement with ČEZ and three weeks ago we signed two important agreements with our strategic partner concerning the actual construction and the future heat supply. One of these agreements regulates the conditions of how much heat we will need and at what price we will buy it.
What will be the next step in the construction of the heat pipeline?
Last year, we assembled an implementation team of workers from our company, which started working on the project. Some of our people are involved in the actual design of the hot pipeline, others will focus on the property rights, as there is quite a large amount of land along the way. It will be necessary to negotiate with their owners.
There are four power-generating units at the Dukovany Nuclear Power Plant. The agreement is that ČEZ will prepare a heat exchanger that will allow the power of the nuclear power plant itself to be taken to the edge of the plant, and Teplárny Brno will invest in a hot water pipeline that will run 42 kilometers towards Brno to the Bosonohy district. Here there will be another transfer point from where the heat will be distributed through two branches around the city. One is the southern one, which will run through the districts of Starý Lískovec and Bohunice and connect to the existing system. The other will lead to Bystrce and on to Medlánky and Královo Pole. It is there that it will connect to the existing hot water pipelines. Teplárny will also implement all measures in the city of Brno so that this heat can be used and supplied to our customers.
The proposed route of 42 km is the shortest possible route, where will the pipeline run?
It is not, because the terrain from the Dukovany Nuclear Power Plant to the connection point in Bosonohy is very rugged. The corridor is based on plans from the 1980s. We have had a number of meetings with the mayors of the municipalities about the route and more are to come. The route will be in the ground, we will be crossing rivers, and the construction will have three tunnels. One is already finished, the other is half-finished. We have verified recently that the construction of the hot water pipeline will go ahead. At the same time, we want to make use of everything we have already prepared. However, the route will not be exactly 42 kilometers long, but it also includes the so-called sinkholes, which will connect our boiler houses to the hot water system.
Will Czech companies build the hot pipeline?
First, we have to design the construction and then we will choose the contractor. The pipeline is designed for 200 megawatts of transmitted power. We will organize tenders where we will clearly specify the conditions and parameters. We have to follow the law. At the moment, we are not deciding whether domestic or foreign companies will bid. It is crucial for us that companies meet all the qualifications we will require.
However, the heat from the Dukovany NPP itself will not be waste heat but will come from cogeneration. Can you describe the principle of these supplies?
We will take some steam from the turbine with parameters that will be predefined. The steam generated in the hot-water exchange station itself will transfer its energy to hot water, which will be transported to Brno via a hot-water pipeline with certain parameters. Realistically, there will be a very small decrease in electricity production at the Dukovany NPP, with current estimates ranging from 0.6 to 0.8 per cent. The price of heat will be priced according to the so-called waste energy. We have set up a price formula with CEZ, according to which we will calculate the price.
Will the plans to build new reactors at Dukovany have any impact on the implementation of the heat pipeline to Brno?
The expected output of the hot pipeline we want to implement is planned for the output of the existing flanks. When ČEZ builds a new unit or there are more units, then heat will be extracted from them as well.
Will there be more heat then?
The Dukovany nuclear power plant has a limited lifetime. It is now planned to last until 2046 and, according to the discussion we have had, ČEZ will try to extend it. However, we assume that when the current units are shut down, we will start drawing heat from the new units.
How many households are to be affected by the new heat pipeline?
We currently supply heat to about 105,000 households in Brno. If we consider that one household is on average two and a half people, we supply heat to 240 to 250 thousand inhabitants of Brno. We now have a network of hot water pipelines and a relatively large number of gas boiler rooms. We assume that we would abolish the boiler houses and build heat exchange stations for the hot pipeline itself. We hope to connect even more customers by 2030. We estimate that the new project would affect about 110,000 households in Brno.
Will the new hot water pipeline bring a major change for your customers? Or will they not know and feel that the heat source will change?
There will be no reduction or change in thermal comfort for our customers. Since 2010, we have carried out a major steam-to-hot water conversion project and there have been relatively large savings for the customers affected. This is because hot water has different parameters than steam. In the case of the new hot water pipeline, instead of heat being supplied by our sources only, it will be supplied by the Dukovany Nuclear Power Plant. However, new hot water heat exchanger stations with modern control will be built, making the heating plant more efficient. Everything will be new, including the piping.
Even the pipes leading directly to the households will be replaced?
Today we have a network of hot water stations and the hot water supplies heat to the heat exchangers. We have them mostly located in apartment buildings or in block stations. We will not change the location, but the older stations will be renovated. In addition to this, we also have more than 110 gas boiler rooms, which are located on the outskirts of housing estates. In the future, we want to completely abolish them and replace them with a small, modern exchange station. The advantage is that the modern technology will be much smaller than the existing outdated boiler houses. For example, new places for rent will be created in the current premises. However, we still want to discuss the specific use with the individual districts.
When is the actual construction to start and when do you expect it to be finished?
The preparatory phase will be ready by 2027, which includes the actual design and land purchases. In 2028 we should start the actual construction and in the autumn of 2030, we would like to start the heat supply. Customers who are connected to gas-fired heating plants should have their first delivery in the heating season in late 2030/early 2031.
What are your biggest concerns about the implementation of the heat pipeline?
I dare say that we have all the projected things firmly in hand. However, the property rights issues will not be easy. We will have to negotiate with the owners of thousands of plots of land. We have to prepare a system that will help us save time. The amendment to the Line Act (effective from 1 January this year - ed.) has helped us a lot because the hot pipeline is a construction of strategic importance. The Czech government's resolution of December 2022 on the Dukovany Nuclear Power Plant's power evacuation project was important for us. The government regards the construction as a strategic project, which we see as a great support. We have done a lot of work with CEZ over the last two years to make sure that everything goes as it should.
As far as the construction phase is concerned, it will be absolutely crucial that we choose the right contractor. Companies must be financially sound and resilient. The aim is to complete all phases on time and on budget.
Since 2010, we have reconstructed more than 65 kilometers of steam pipes in Brno and replaced them with hot water pipes. We have only had the period from May to August to complete the work and have always managed to rebuild 4 to 5 kilometers, including key streets in the city. Among other things, the projects we have managed have given us the confidence that we should be able to build the hot water pipeline.
How much will it cost to build the hot water pipeline and where will the money come from to implement it?
Finance is a key issue. In our discussions with CEZ, we are talking about CZK 19 billion; this is the projected expenditure in 2030. If we were to apply this model to the present, it is roughly CZK 14 billion. Roughly two billion crowns should go to CEZ - this will be for the removal and preparation of heat to the edge of the nuclear power plant, and 42 kilometers of the hot pipeline will cost us roughly eight billion crowns. The rest of the funds will go to investments related to infrastructure in Brno itself. For the record, if we had built the hot pipeline this autumn and switched to the new heating source from Dukovany, we could have reduced the price of heat by around 20 percent. And that's even after deducting the projected costs.
Have you looked at the hot water pipeline that runs from the Temelín NPP and supplies heat to České Budějovice? Do you have a model of a similar project abroad?
We have been following the construction in Temelín for a long time, and this year we are going to the nuclear power plant during the summer shutdown. We have also studied countries where similar applications are located, for example in France or Scandinavia. We are also planning a business trip to gain foreign experience of how they built a similar hot water pipeline and how they communicated with the public, for example.
However, the newly built hot pipeline will not replace all the gas that Teplárny Brno uses today. What sources will you use to make up the difference?
Teplárny Brno currently has four production sources plus one cooperating source, which is Sako Brno (Municipal Waste Incineration Plant, a company 100 owned by the city of Brno - ed.). Sako is currently preparing a project to build a third boiler. We expect that in the future, about 25 percent of the heat needed by Brno residents will be produced by burning waste. The other part of the heat will come from a large wood chip source that will burn woody biomass. We will produce heat and electricity from this. We expect its construction to be completed in the autumn of next year. This heat source will replace about 15 percent of the gas and the rest will be supplied from Dukovany. A small part, about five percent, will remain. These are localities where it is not worth building anything; we will continue to produce heat for these areas using natural gas. However, thanks to all the projects that have been implemented, we will have a fuel mix that will be much more stable. Thanks to this, Brno will be completely self-sufficient.
In addition to the heat supply, your business also supplies electricity and gas. Is the number of your customers growing?
Teplárny Brno is not only a heat producer, but also a large producer of electricity. More than 90 percent of our heat is produced in cogeneration. A few years ago, we adopted a strategy and started offering electricity to smaller consumers, not just businesses. At present, we have about 4,000 households that buy electricity from us. In 2020, we started to build a network of charging stations, and today we have about a thousand customers who take energy from us to charge their electric vehicles. Last October, we established a subsidiary, Energie Teplárny Brno, which will supply electricity and gas to all the city's institutions from 2025. The supplies cover around 260 buildings, including the city hall, theatres, district offices and contributory organizations.
Do you hope to be there when the new hot water pipeline is launched?
I would like to start the heat from the new hot water pipeline with a symbolic turn of the tap. It would also be a great honor for me to be at the very end of the project. But it will undoubtedly be a very demanding event. We are approaching the project with humility and first and foremost with the residents of Brno and other districts that may be connected to the hot water pipeline in mind. We must do everything we can to prepare everything in the first phase and bring the whole project to a successful conclusion.
Source: Mladá fronta Dnes