Stuttgart-Münster combined heat and power plant generates reliable, economical and environmentally friendly energy for the mid-Neckar region. The site’s focus is on recycling waste. Alongside a hard coal-fired block that will continue to operate until spring 2026, two gas turbine plants and a waste incineration plant produce electricity and district heating in combined heat and power mode. As a waste-to-energy plant, it plays an important role in the disposal of residual waste in Baden-Württemberg. In addition, a large-scale heat pump generates district heating via its cooling water discharge. EnBW intends to phase out coal-fired power generation by 2028, provided the framework conditions allow this. As part of this strategy, the site has been converted to run on hydrogen in the future (known as a fuel switch): A new gas turbine plant is currently being operated using natural gas, with hydrogen set to be used at a later date. It will then be able to generate carbon-neutral electricity and district heating.
We offer free guided tours of Stuttgart-Münster combined heat and power plant all year round – with expert information provided by our employees. Find out more >
Fuel Switch
Project introduction
In terms of its own emissions, EnBW plans to become climate-neutral by 2035 and is consistently continuing the decarbonization of its generation portfolio with the rapid expansion of renewable energies. Due to legal requirements, all coal power plants in Germany must also be shut down by no later than 2038, including the plant in Stuttgart-Münster. The most important consideration in the region, however, is guaranteeing security of supply for electricity and district heating, which is why EnBW has built a controllable, hydrogen-ready gas turbine plant at the site:
- The new, gas-fired plant can achieve a much higher fuel utilization rate than other types of power plants.
- In addition, carbon emissions and other pollutants – such as dust, sulfur dioxide and nitrogen oxides – are significantly reduced or, in the case of heavy metals, eliminated altogether.
- As a result of this fuel switch to natural gas, the coal phaseout for the Stuttgart city area has already been completed many years ahead of the legally stipulated date.
As soon as enough hydrogen is available and the supply infrastructure has been converted to accommodate it, the power plant will be able to produce carbon-neutral electricity and district heating. A certain hydrogen blend ratio can be burned from the moment the plant is commissioned – complete combustion of hydrogen requires the gas turbine to be converted, which can be done at any time during one of the routine major overhauls. This means that the switch to hydrogen can be made at a later date with no major hurdles. Find out more about the fuel switch here.
Technology
The gas turbine plant is replacing the existing three coal boilers in the hard coal block:
- There is a so-called common steam range on the site. All on-site power plants feed the steam they generate into this large steam pipe.
- The high-pressure steam is then channeled along the common steam range to the steam turbines (two condensing and one back-pressure turbine), which produce electricity and district heating.
- The new gas turbine plant also feeds the steam it generates into the common steam range, which means that the existing infrastructure is used
The district heating produced in the course of electricity generation is fed into the “Mittlere Neckarschiene” district heating network, which is also connected to the Altbach/Deizisau combined heat and power plant and the Stuttgart-Gaisburg combined heat and power plant. It is used to supply many industrial companies, private households and public buildings in Altbach, Deizisau, Esslingen, Plochingen and Stuttgart.
Large-scale heat pump
In addition to the fuel switch, another significant step toward making the district heating supply climate-neutral in the Stuttgart region has already been taken at the site. Since April 2024, a large-scale heat pump has been using the waste heat from the cooling water discharge to generate up to 24 megawatts of district heating. The pump sets new standards in terms of how waste heat is used to meet energy needs and is one of the first of its kind in Germany on this scale. One challenge involved integrating the new heat pump into the power plant’s existing infrastructure while maintaining ongoing operations. The project was funded by the German Federal Ministry for Economic Affairs and Climate Action as part of the ideas competition “Reallabore der Energiewende” (or “Field labs for the energy transition”) and is part of the joint research project “Large-scale heat pumps in district heating networks.” The investment costs ran to around 17 million euros.
The heat pump technology, familiar from building heating applications, is used on a large scale in Stuttgart-Münster. By extracting the required environmental heat from the power plant’s cooling water, the large-scale heat pump consequently reduces the amount of heat discharged into the Neckar and uses the energy contained in the cooling water to generate climate-neutral district heating. Powered by certified green electricity generated from waste incineration, the large-scale heat pump can cut carbon emissions by around 15,000 metric tons annually and increase the share of climate-neutral district heating in the Stuttgart region by around 10% to approximately 25%.
Approach
Project phases
This is where we inform you about important events and milestones relating to the planning and construction of a gas turbine plant on the Stuttgart-Münster site. You will find the latest information here on the timetable for the planning and approval process as well as the progress of the construction work.
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May 2025
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Commercial commissioning of the large-scale heat pump
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April 2025
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Official commissioning of the gas turbine plant (fuel switch)
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October 2024
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The gas turbine plant’s hot startup phase begins
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April 2024
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Official commissioning of the large-scale heat pump
Gas turbines delivered and moved into position |
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November 2023
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Commissioning work starts on the large-scale heat pump
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31 March 2023
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Groundbreaking ceremony for the new building housing the gas turbine plant and the large-scale heat pump
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October 2022
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Stuttgart Regional Council meeting to discuss the project
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22 March 2022
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Investment decision taken by EnBW’s Supervisory Board
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21 July 2021
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Project presented to Bad Cannstatt council committee
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23 April 2021
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Scoping-Meeting0In complex planning processes, a scoping meeting is held by the authority overseeing the process (in this case Stuttgart Regional Council). With the involvement of public agencies and specialist authorities, the meeting is used to formally determine the subject, scope and methodology of the regional impact and environmental impact studies as well as the content of the application documents that need to be drawn up.
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20 April 2021
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Project presented to Münster council committee
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13 April 2021
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Virtual information event for the public
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12 April 2021
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Information event for professional associations and citizens’ initiatives
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Project diary
April 2025: Power plant open day
On 13 April 2025, we celebrated the official commissioning of the fuel switch power plant by holding a power plant open day together with the public. In addition to guided tours of the new H₂-ready gas power plant and the waste-to-energy plant, there was an extensive program of activities for children. The Bad Cannstatt musical society created a lively atmosphere in the marquee. We are delighted that the power plant open day went down very well with a total of around 2,700 visitors.
April 2025: Official commissioning of the fuel switch power plant
Ready for hydrogen with around 60 percent fewer carbon emissions: Following the official commissioning of one of Germany’s first H2-ready gas power plants on 11 April 2025, we have reached a milestone in terms of climate-friendly energy supply. In total, the new power plant has an electrical output of 124 MW and a thermal output of 370 MW. Together with waste incineration, the entire site will be capable of generating 450 MW of heat in the future. Stuttgart has thus become one of the first major coal-free cities in Germany. We had the pleasure of celebrating this occasion together with our hosts, EnBW CEO Dr. Georg Stamatelopoulos (right) and our Board Member for Generation Peter Heydecker (left), as well as our guests (from left) CEO of Siemens Energy, Dr. Christian Bruch, Stuttgart’s Mayor Dr. Frank Nopper and State Secretary Dr. Andre Baumann.
Get an insight into events on the construction site leading up to the commissioning process here.
November 2024: The hot startup phase continues. The waste heat boilers are now being commissioned following the gas turbine test runs. These boilers use the hot flue gases from the gas turbines to generate steam, which in turn produces both electricity and district heating. As part of the commissioning process, the steam pipes were blown down on several days between the end of October and the end of November. This involves steam being discharged from a separate pipe, which generates noise. Silencers were installed to minimize any such noise. The process is necessary in order to be able to safely commission the plant in 2025.
October 2024: The “hot startup” phase in Stuttgart-Münster begins. The construction process that started back in January 2023 reached the so-called “hot startup” phase for the first gas turbine this week. The former coal boiler and heating oil-driven turbines have been replaced by a highly efficient gas turbine system with an output of 124 megawatts. To check whether everything is working as intended, tests will now be carried out repeatedly over several days. This includes gradually increasing the output of the gas turbines to adjust and test them for optimum operation. It will be possible to see the flue gases generated during the combustion process as they are discharged from the newly constructed chimney, just like the flue gases from the chimney for the existing waste and coal boiler.
September 2024: An ABC of the pipelines. Different brightly colored pipelines can be seen running along the pipe bridges and through the highly efficient gas turbine plant. Installing these pipelines on the construction site takes a lot of time. But what is being transported by which pipeline?
Green:
- A cooling water pipeline providing water to cool the gas compressors with a total length of approx. 340 meters
Yellow:
- A high pressure natural gas pipeline running from the gas control pressure measurement station to the gas turbines via the compressors with a total length of approx. 290 meters
- A low pressure natural gas pipeline running to the hot water boilers, waste heat boiler and existing plant with a total length of approx. 450 meters
Grey/brown:
- A district heating pipeline in the M1 grid supplying downtown Stuttgart with a total length of approx. 130 meters
- A district heating pipeline in the M2 grid supplying North/West Stuttgart with a total length of approx. 1,300 meters
August 2024: Delivery and installation of the transformers. In August 2024, four transformers, two auxiliary power transformers and two generator transformers were delivered on heavy goods vehicles and installed. The generator transformers each weigh 106 metric tons and convert the generator voltage into the voltage used in the high-voltage public grid. This means that the electricity can be fed directly into the public grid. The auxiliary power transformer are lighter and each weigh 27 metric tons. They convert the generator voltage into the medium-voltage electricity required by the power plant itself to efficiently cover the plant’s electricity needs (such as for pumps, control systems and lighting) from own generation.
More insights can be found here.
June 2024: East pipe bridge lifted into position. The four sections of the east pipe bridge were lifted into place in June. The bridge connects the existing power plant with the gas turbine plant that is currently under construction. The pipe bridge is approx. 43 meters long and weighs a total of 110 metric tons. It carries, among other things, the pipes for ammonia water, fresh steam, heating oil and demineralized water.
May 2024: Delivery and lifting of the waste heat boiler chimney elements. At the end of May, the chimney elements for the waste heat boiler were delivered on heavy goods vehicles and lifted into place with a crane that can lift up to 500 tonnes. The two chimneys each consist of 2 segments and are 5.2 meters in diameter, 15 meters tall and weigh around 30 tonnes. They will be used to discharge the combustion gases generated during operation of the gas turbine plant. They also contain an emission measurement system for each of the two gas turbines, so that compliance with the permissible emission limits can be monitored at all times.
You can find more insights here.
April 2024: Official commissioning of the large-scale heat pump. On 8 April 2024, the large-scale heat pump at the Stuttgart-Münster waste-to-energy combined heat and power plant was officially commissioned by EnBW CEO Georg Stamatelopoulos, Minister for the Environment, Climate Protection and Energy Sector of Baden-Württemberg, Thekla Walker, and the Mayor for Urban Development, Housing and the Environment, Peter Pätzold. This large-scale heat pump with an output of up to 24 MW is one of the most powerful systems in Germany. It will reduce carbon emissions by around 15,000 tonnes per year and can supply about 10,000 households with climate-neutral heat.
April 2024: Delivery and assembly of the gas turbines. In April, the two SGT-800 gas turbines were delivered to the construction site and installed. A gas turbine is a heat engine that converts thermal energy into rotational energy. An electrical generator uses this rotational energy to generate electricity. Exhaust gases leave the gas turbine at a very high temperature and can be reused to generate heat, steam and even more electricity. The two gas turbines have a total electrical output of 124 MWel. You can find more insights here.
February 2024: Start of construction of the black- start battery system. A black-start battery system is being built at the Stuttgart-Münster site. Construction work began in February 2024. The power required to start up the power plant at the site can be covered by the black-start battery system in combination with the gas turbines. The CO₂-neutral black-start battery system is also able to provide primary and secondary control power at short notice and thus help to stabilize the grid.
January 2024: Delivery and installation of the hot water boilers and associated chimneys. The three hot water boilers were delivered and installed in January 2024. Immediately afterwards, the three approx. 60-meter-high chimneys were lifted into place in 3 segments each. You can find more insights here.
December 2023: Commissioning of the large-scale heat pump. Commissioning of the large-scale heat pump began in December 2023. The large-scale heat pump will utilize the waste heat from the cooling water discharged at the site to generate up to 24 MW of district heating. The climate-neutral district heating generated in this manner will cut carbon emissions by around 15,000 tonnes per year. The heat pump will thus not only make an important contribution to the decarbonization of EnBW's district heating generation, but also significantly help the City of Stuttgart to achieve its climate protection goals. You can find more insights here.
November 2023: Lifting of the northern pipe bridge. On 03.11.2023, the northern pipe bridge over Neckartalstraße was lifted into place in cooperation with SSB and the city of Stuttgart using a tandem lift with 2 cranes. The pipe bridge was installed on site before being lifted into place, including the district heating and natural gas pipes for supplying the city of Stuttgart. The natural gas pipelines are already 100% H2-ready.
October 2023: Delivery and assembly of the first waste heat boiler for the gas turbines.The components of the first waste heat boiler were delivered by heavy goods vehicle at the end of September. The individual components that ultimately make up the waste heat boiler are welded together piece by piece and assembled. The waste heat boiler utilises the heat recovered from the gas turbine to generate steam and hot water to drive the steam turbine. When fed into the respective grids, district heating and electricity are generated.
September 2023: Delivery and installation of the large heat pump.The components of the large heat pump were delivered and installed at the beginning of August 2023. Components such as the evaporator, intercooler and condenser were delivered and installed in various partial deliveries. The large heat pump can generate up to 24 MW of green district heating. This can save around 15,000 tonnes of CO₂ per year.
August 2023: Steelwork for the gas turbine building. Work on the steel structure for the gas turbine building began in mid-July 2023. The two gas turbines, each with a capacity of 24 MW, will be housed in the gas turbine building along with the waste heat boilers and two chimneys. The gas turbine building will be constructed as a steel skeleton frame using approx. 1,300 metric tons of steel girders and its dimensions will be approx. 65.20 x 45.15 x 34.00/17.80 meters (L x W x H). The main structure of the steel skeleton frame generally consists of a series of steel columns and horizontal beams connected by means of riveting, bolting or welding. This construction method enables rapid progress to be made, with completion already scheduled for mid-May 2024.
July 2023: Construction of the stair tower. In July 2023, construction began on the approx. 32.4-metre-high stair tower, which adjoins the district heating building to the south by means of bridges and the hot water boiler plant to the north.The special feature is that the stair tower was concreted using slipforming. Slipforms are used when jointless structures or short construction times with high daily output are required. The stair tower was erected within 6 days in 24-hour shift operation.
June 2023: Chimney foundations with integrated crane support. In keeping with the motto 2 in 1, the chimney foundations were used as a crane support. The crane was erected using a built-in part that serves as a rear anchor to stabilize the crane. The 60-meter-high crane has a working radius of up to around 60 meters and can thus cover almost the entire construction site. In 2024, the chimney will then be built using the slip form method. This approach guarantees a flexible, efficient and economical construction process.
May 2023: Concrete casting and reinforcement of the gas turbine building. Once the foundation work was completed, the reinforcement work started, along with the concrete casting in stages for the two gas turbine foundations. Approximately 600 m³ of concrete were needed for each of the foundations, which is the equivalent to around 3,000 bathtubs per foundation. It took 130 concrete mixers and two concrete pumps to complete the job. The concrete structural elements are reinforced using steel, increasing the load-bearing capacity of the building being constructed on them. The 124 MW gas turbines are housed in the gas turbine building.
April 2023: Installation of the driven piles. Work on installing the 202 driven piles began in April. Pile foundations are deep foundations where the loads of supporting structures are transferred to deeper soil layers with a higher load-bearing capacity. Soil layers with poor load-bearing capacity are thus bridged using piles. With so-called pile foundations, the piles are driven into the ground with a pile driver until a soil layer sufficiently capable of bearing the load has been reached. Concrete is then poured into them.
March 2023: Groundbreaking ceremony and official opening of the building site. The starting signal was given in Stuttgart-Münster for the construction of the new gas turbine plant and large-scale heat pump. Minister for the Environment, Climate Protection and Energy Sector for Baden-Württemberg Thekla Walker, Mayor Dr. Frank Nopper and the EnBW Board Member responsible for sustainable generation infrastructure Dr. Georg Stamatelopoulos performed the traditional groundbreaking ceremony on 31 March 2023.
February 2023: Start of foundation works. Foundation works create a stable and load-bearing basis for the buildings and machinery associated with the new plants. This covers groundwork such as the excavation of pits and the construction of the foundations, including pile foundations.
January 2023: Start of construction works at Stuttgart-Münster. The construction project got under way in Stuttgart-Münster on 9 January 2023 and work has been continuing ever since. The start of construction also sees the introduction of a temporary alternative traffic management concept:
- A contraflow system for traffic traveling out of town at the intersection of Neckartalstraße/Voltastraße
- Normal flow of traffic resumes at the intersection of Neckartal-/Haldenstraße
- City-bound traffic uses the remaining lane with suspension of the cycle lane on Neckartalstraße
This traffic concept means that no major diversion is needed for car traffic. Cyclists are diverted via the Neckartal cycle path. This allows the routes at the Voltastraße intersection to remain open.
Frequently asked questions – and our answers
Here you can see at a glance the advantages of the gas turbine plant over the hard coal block that has been used until now:
- Natural gas is a more climate-friendly fuel than hard coal. The gas turbines emit around 60% less CO₂ and are large enough to replace coal capacity beyond Münster.
- Air pollutants will be reduced. Nitrogen oxide emissions will be cut by about 45%, while sulfur oxide emissions and dust pollution will be almost completely removed and heavy metal emissions eliminated altogether.
- Due to the decommissioning of the coal blocks, the existing coal storage facility is no longer needed, putting an end to the associated dust and noise emissions.
- There will be less traffic. Coal deliveries will no longer be needed, nor many of the journeys to deliver additives and dispose of residual materials from the flue gas cleaning process.
- Der Lärm wird dank moderner Schallminderungstechnik stark verringert. Die Kohlekessel, kohlebefeuerten Hilfsdampferzeuger und die Rauchgasreinigung werden zudem stillgelegt.
- The warming of the Neckar will be significantly reduced, especially in summer. Heat exchangers in rooftop units will ensure that no additional cooling water has to be withdrawn.
- The district heating supply will be secure. New, more efficient systems will replace the older supply infrastructure in the Stuttgart Northwest and Cannstatt district heating networks.
The goal of climate neutrality is neither achievable for individual companies nor entire states in a single step. With regard to heat generation in particular, renewable energies are not yet in a position to fully replace fossil fuels in the short term. Replacing coal with natural gas is therefore a sensible intermediate step because it can roughly halve greenhouse gas emissions compared to coal in the short term and therefore significantly reduces carbon emissions.
This is especially the case when indirect emissions generated by mining and transport are taken into account. That’s because the fuel switch also avoids indirect emissions associated with coal mining and transport, such as emissions of mine gas, which has a high methane content. The nice thing is that a natural gas power plant does not stand in the way of the ongoing journey toward climate neutrality. The gas turbines used are very flexible and can be converted to burn “green gases” in the future, including hydrogen, which is produced by means of electrolysis using electricity from renewable energy sources..
Accordingly, the switch to natural gas represents a bridge on the way to green gases, with which complete climate neutrality can then be achieved by 2035.
If work begins in the first quarter of 2023, the new building should be completed in mid-2025.
The project is currently going through a staggered approval process. We received a preliminary approval decision and the first partial approval in January 2023. The second partial approval is expected to be submitted in February 2023. The so-called scoping meeting was held at the start of the approval procedure, during which the scope of the environmental impact assessment was discussed and defined.
There were buildings on the planned construction site of the new facilities. On the one hand, Netze BW operates a 110kV transformer station at the site. This was replaced by a new building to the west of the planned power plant, which has already been put into operation. For this purpose, feeder lines were relocated. The dismantling of the 110 kV switching station of Netze BW was completed in the first half of 2023.
In addition, the workshop for EnBW's power plants at the Stuttgart Münster and Stuttgart-Gaisburg sites was located on the relevant site. Planning for a new building was also taking place here. This will have to be replaced in the next few years - irrespective of the new construction project - as it no longer corresponds to the current state of the art and EnBW aims to continue to maintain a large part of its power plant park itself in the future. The completion of the new workshop has been completed. Demolition of the old workshop was completed at the end of 2022.
Once the new plants are supplying district heating, the coal dump can be taken out of operation. A decision is yet to be taken as to how the areas will be used in the future.
The confined location of the power plant site inevitably means that the construction work will be felt in the surrounding area. However, EnBW will endeavor to keep the impact to a minimum and remain in dialog with local residents.
For example, an engineering firm has already been tasked with drawing up a traffic management concept to keep the construction site traffic separate from the flowing traffic. The new traffic management concept is described in the “Project diary” section.
Construction work will mostly take place during the day, with heavy loads being transported at night wherever possible. All construction measures will be carried out and observed as per the approval process in close consultation with Stuttgart Regional Council and the city of Stuttgart.
Various expert reports need to be commissioned as part of the approval process, which also consider any impact on the residents. Among other things, sound reports and air pollutant immission forecasts are compiled, which consider the impact of the new building on the surrounding area and the environment:
- Noise control: Once the new plant has been commissioned, the old plants – including the coal boilers, the coal storage facility and the flue gas cleaning system for the coal boilers – will be shut down. Besides the waste boilers and their auxiliary systems, these have been one of the sources of noise at the site until now. The new plant will be equipped with state-of-the-art sound absorbers, sound traps, etc. in order to stay within legal limits as specified in noise control guidelines (TA Lärm). In addition, there will no longer be any disposal of residues or delivery of additives associated with the coal boilers’ flue gas cleaning system, which will in turn reduce the volume of traffic and the resulting noise.
- Water pollution control: The newly built power plant facilities do not require any additional withdrawal of cooling water from the Neckar. Instead, the gas turbine CHP plant is cooled by heat exchangers installed on the roof of the building in a separate water-glycol system. They permanently reduce the heat discharged into the Neckar via the cooling water. Particularly when temperatures are high in the summer and the demand for district heating is lower than the amount of heat produced in the continuous waste incineration operation, the water currently has to be discharged into the Neckar via the cooling water system. In the future, the heat discharged should be kept to a minimum by the new heat exchange system in order to counteract warming in the Neckar. Particular care is being taken here to ensure that the units are both efficient and quiet.
- Immission control: Due to the location of the boiler, the urban area in particular is exposed to pollution caused by industry, traffic and residential buildings – especially particulate matter and nitrogen oxides. The switch from coal to gas at the Münster site will have a significant positive impact here. Based on initial calculations, nitrogen oxide emissions will be reduced by more than 45% and particulate matter by about 88% compared to the coal boilers currently in operation. Emissions of heavy metals are also reduced to almost zero as a result of the fuel switch. The reduction is partly attributable to the highly efficient combustion technology used in gas turbines, but also due to EnBW’s planned use of SCR technology, which involves using catalytic converters in the flue gas system of gas turbines, thereby reducing emissions of nitrogen oxides (NOx) to a greater extent than required by the already strict legal requirements for gas turbine plants.
Until all new power plant and district heating facilities have been fully commissioned, the coal boilers will remain available for supplying district heating. By taking this approach, we will ensure that supplies in Stuttgart and the surrounding region are reliably guaranteed at all times.
Private households as well as industrial companies and public institutions will be supplied with district heating in Stuttgart. You can check here whether district heating is available in your area. EnBW regularly examines the connection of new city districts.
By using district heating for their heating and hot water, citizens can play a key role in mitigating climate change. District heating is produced with combined heat and power plants, which cuts carbon emissions and increases the efficiency of the plant. Less space is required due to the compact nature of the stations, because a boiler, tank and flue gas system, including chimney, are no longer needed, thereby also eliminating the costs associated with them.
Throughout the project, EnBW will keep people regularly updated on its progress and report on milestones on the website www.enbw.com/stuttgart-muenster. On 13 April 2021, a public online information event was held, during which the project was presented to citizens. People who took part were able to put questions live to those present in the studio.
However, you can always send any questions, suggestions or criticism by e-mail to stuttgart-muenster@enbw.com.
The project falls under Number 1.1 of Annex 1 of the Fourth Regulation on the Implementation of the Federal Immission Control Act (Regulation on Plants Requiring Approval, 4th BImSchV). Pursuant to Annex 1 Number 1.1.1 Column 1 in conjunction with Section 3b of the Environmental Impact Assessment Act (UVPG), there is a duty to carry out an environmental impact assessment. The environmental impact assessment is an integral part of the approval process pursuant to BImSchG (Section 1 Paragraph 2 of the Regulation on the Approval Process (9th BImSchV)) and is conducted by Stuttgart Regional Council as the competent approval authority.
The project is set to be approved in a phased approval process with a preliminary decision on the approval requirements pursuant to BImSchG and environmental law and a further decision on the release of greenhouse gases (carbon dioxide) pursuant to the Greenhouse Gas Emissions Trade Act (Treibhausgas-Emissionshandelsgesetz or TEHG) and two partial permits for the construction and operation of the Stuttgart-Münster fuel switch plants.