Building and operating a grid stabilization plant

To ensure grid stability and security of supply, additional generation facilities ("special grid-related equipment in accordance with Section 11 (3) EnWG") are required as part of the Energiewende. EnBW is currently constructing such a grid stability facility at its power plant site in Marbach am Neckar. Following completion of the approval process in accordance with the Federal Immission Control Act (BImSchG) in July 2020, the plant is currently under construction. Due to delays, commissioning is targeted for 2023.

Project diary

This is where we inform you about important events and milestones relating to the planning and construction of the grid stabilization plant on the Marbach 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.

Project timeline

29 November 2018	Citizen information Energy and technology park at Marbach power plant Reinhold-Würth-Straße 4 / Am alten Kraftwerk, first floor
December 2018	Scoping meeting* for Stuttgart Regional Council
August 2019	Contract awarded to EnBW upon completion of the tendering process
3rd quarter 2019	Application submitted for approval in line with immission control regulations
3rd quarter 2019	Start of work on existing 110 kV plant at the site
July 2020	Approval granted and start of construction
December 2021	Approval change
April 2022	Grid connection completed
July 2022	Commissioning of demineralization plant
2023	Commissioning of grid stabilization plant

* In 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.

Construction diary

June 2023

Insulation work is carried out on the completed outdoor pipework.

May 2023

The cables are installed and connected to the switchgear.

April 2023

The cable routes are built in the switchgear building.

March 2023

Installation of pipework and pipe skids – the heating oil pumps in the pump house can be seen here.

February 2023

All filter and silencer banks were installed for the air intake.

January 2023

Bringing in and installing the switchgear in the switchgear building.

December 2022
Construction of the pipeline bridge for the oil and cooling water pipes.

November 2022
Completion of the switchgear room interior..

October 2022

Preparation of the air filter plates for the air intake.

September 2022

The pipework in the pump house takes shape.

August 2022

At the start of August, the last of the eight segments were lifted into position on the 80-meter chimney.

July 2022

Installation of the ventilators on the heat exchanger.

June 2022

Chimney segments three, four and five are hoisted into position. All eight segments will be in position by August.

May 2022

At the heart of the power plant, the 300 MW gas turbine, the structural parts are attached.

April 2022

The chimney is made up of eight segments. These silencer units are installed in three segments in order to comply with the low noise immission limits.

March 2022

The concrete formwork helps the switchgear building to take shape. In the foreground is the 220 kV transformer, which is almost fully assembled.

February 2022

The second of eight chimney segments is lifted into position.

January 2022

Completion of the groundwater pumping rooms.

December 2021

Cladding the turbine hall facade.

November 2021

Construction of the plant technology in the water treatment plant is progressing according to plan. Pictured are the different filter lines in the plant used to produce the deionized water.

October 2021

Installing the diffuser, which is located between the gas turbine and the chimney.

September 2021

Works on the portal for the 220 kV connection.

August 2021

Construction work on the turbine hall continues with the gas turbine positioned inside.

July 2021

At the end of July, the three major components arrived by barge: gas turbine, generator and transformer Their journey began back in June on a container ship in Genoa. Traveling via Antwerp, the three large components ultimately continued along the Rhine and Neckar to Marbach on a barge. At the same time, work had been ongoing since mid-July to transform the parking lot of Marbach Technology Park into a temporary harbor to enable two large cranes to be set up. Here, by the quayside, they unloaded the heavy plant components: The generator weighs 378 metric tons, the turbine 317 tons and the machine transformer 270 tons. On the power plant construction site, they were positioned and installed on their respective foundations using special lifting and moving equipment.

June 2021

The gas turbine was loaded onto the ship in Genoa. It is due to arrive in Marbach in July.

May 2021

Concrete formwork for the gas turbine foundations.

April 2021

The 10-meter-long rotor on the 300 MW gas turbine weighing 85 metric tons was subjected to a so-called “balancing run” and “overspeed test” and passed with flying colors. The first rows of blades on the turbine must be capable of withstanding a temperature of over 1000°C at 3000 revolutions per minute during operation.

March 2021

A bird’s eye view reveals the water treatment plant building in the bottom left-hand corner of the picture. In the middle of the picture are the reinforcements and foundations for the power plant’s various buildings, with the large gas turbine foundation in the center.

February 2021

The concrete formwork for the walls is now added to the finished floor slab of the water treatment plant. All against the backdrop of a yellowy Sahara dust sky.

January 2021

The floor slabs for the water treatment plant are completed.

December 2020

Following soil improvement measures on the construction site, the granular subbase is now laid. The foundations are then built.

November 2020

The floor slabs for the water treatment plant are made.

October 2020

Construction work officially began on 12 October 2020 with the symbolic groundbreaking ceremony attended by (from left) Dirk Güsewell, Head of Generation/Portfolio Development at EnBW, Jan Trost, Mayor of Marbach, Hans-Josef Zimmer, EnBW Chief Technology Officer, Franz Untersteller, Minister for the Environment, and Werner Götz, TransnetBW Managing Director.

September 2020

As part of soil improvement measures, a total of around 1,800 gravel and concrete columns are now placed in the subsoil in order to increase the load-bearing capacity in the area of the gas turbine plant and in the area of the demineralization plant.

August 2020

The topsoil is removed from the construction site and the assembly and storage area is graveled.

July 2020

16 July 2020: The Regional Council grants approval in line with the Federal Immission Control Act for the Marbach 4 grid stabilization plant, marking a very important milestone – and even one month ahead of schedule. The approval process took eleven months from the initial application submission date. A decision on the application was made about five months after the application was completed, one month sooner than the statutory period of six months. At the same time, the EnBW container village was installed on the construction site – enabling construction work to begin.

June 2020

The quantity and quality of the well water for the water treatment plant are tested in a large-scale pumping test. Impurities and dirt particles are filtered in the settling tank

May 2020

Work on the power supply for the construction site is completed in May. The 10 kV cable for supplying power to the later water treatment plant has also been laid.

April 2020

The construction disclosure process and subsequent one-month objection period ends on 20 April with no objections.

March 2020

The application for project approval is open to public consultation until 20 March 2020 at Stuttgart Regional Council and the planning office for the town of Marbach am Neckar. Anyone with a legitimate interest may officially participate in the consultation and make suggestions, raise concerns, etc. In addition, we invite you to get in touch directly with the project team. You can do this by sending an email to netzstabilitaetsanlage@enbw.com.

February 2020

Initial work is carried out on the construction site where the new grid stabilization plant is set to be built. The building ground is analyzed, for example, in order to be able to definitively determine the position of the power plant’s foundations. In addition, the site must be examined for possible ordnance because it was shelled with grenades in the Second World War (pictured: excavation of a suspected explosive ordnance case with nothing found).