German energy company EnBW has commissioned one of the first hydrogen-ready gas turbine units in Germany at the Stuttgart-Münster power plant. This project is part of a large-scale modernization of the plant, aimed at decarbonizing the energy system and increasing generation flexibility.

Key changes at the CHP plant

Replacement of outdated capacities

• Previously, the plant operated three oil-fired turbines and three coal-fired boilers, which were used for peak power supply and heating.
• After the modernization, two new Siemens gas turbines with a total capacity of 124 MW (el.) and 370 MW (thermal) were introduced.
• Together with the waste incineration units, the total thermal capacity of the plant reached 450 MW, which covers 17% of Stuttgart’s heat needs.

Heat pump for heat recovery

• Since April 2024, a 24 MW heat pump has been operating at the plant, which takes heat from the return flow of the district heating system and reduces the heat load on the Neckar River.

Complete phase-out of coal and fuel oil by 2026

• After a short transition period, the coal unit and fuel oil turbines will be permanently decommissioned.

Plans for the transition to hydrogen

• From the mid-2030s, EnBW plans to use 100% low-carbon hydrogen (subject to availability).
• The project is seen as a pilot for future flexible power plants needed to balance the energy system with a high share of renewable energy sources.

Hydrogen energy: pros and cons

Advantages

Flexibility of generation – hydrogen turbines can compensate for dips in solar and wind energy generation. Decarbonization – using “green” hydrogen does not emit CO₂.
Compatibility with existing infrastructure – upgrading gas-fired CHP plants is cheaper than building new ones.

Challenges

• High cost – producing “green” hydrogen is still expensive, and its mass supply is not established.
• NOx emissions – burning hydrogen produces nitrogen oxides, which are harmful to health and the climate (although purification technologies exist).
• Low efficiency – direct combustion of hydrogen is less efficient than using fuel cells.

Global context: hydrogen thermal power plants

• Hyflexpower (2023, France) – the first industrial gas turbine from Siemens on 100% hydrogen.
• Equinor (UK) – plans to build a large hydrogen power plant (still in the early stages).
• South Australia (2024) – the project of the world’s largest hydrogen thermal power plant with GE Vernova turbines.

Conclusion

The modernization of the Stuttgart-Münster CHP plant is an important step for Germany to abandon coal and switch to hydrogen. However, the success of this strategy depends on the development of the hydrogen economy and government support. For now, hydrogen combustion remains a compromise solution, but in the future it may become one of the elements of low-carbon energy.