From coal to natural gas to hydrogen

By constructing a new combined cycle gas turbine (CCGT) plant, EnBW wants to replace coal with more climate-friendly natural gas at its Altbach/Deizisau site by means of a so-called fuel switch. This switch to natural gas represents the bridge that will ultimately lead to green gases such as hydrogen produced from renewable sources. EnBW thus plans to keep its promise of achieving climate neutrality by 2035 – the company’s contribution to climate change mitigation to which it has committed itself in line with the 2015 Paris Agreement. With this aim in mind, EnBW will continue to systematically expand renewable energy capacity and completely phase out the use of coal as an energy source in the medium term. In doing so, the number-one priority is to ensure that the supply of electricity and heat is never under threat.

A combined cycle gas turbine (CCGT) plant is one in which the principles of a gas turbine power plant and a steam power plant are combined. It involves a gas turbine producing electricity via a generator. The flue gases from the gas turbine, which are still around 600°C, are then fed through a downstream waste heat boiler in which steam is generated to power a steam turbine. The steam turbine also drives a generator to produce electricity. By combining these two principles, the energy released during the combustion of the gas is effectively used twice, thereby achieving a higher degree of efficiency – up to 60 percent.

• The new CCGT plant has a maximum electrical output of 750 _el
• Through district heating extraction, the CCGT plant has a thermal output of approx. 180 MW_th
• The planned hot water boiler plants used to secure the district heating deliver a thermal output of 120 MW_th

• The new gas-fired CCGT plant can be controlled more flexibly than a coal power plant and can therefore better complement the fluctuating production of electricity from wind power and solar energy.
• As a fuel, natural gas is much more climate-friendly than hard coal and will more than halve greenhouse gas emissions per kilowatt-hour of electricity generated from 2026.
• Airborne pollutants are also significantly cut: In terms of the overall location, NOx emissions will be reduced by approx. 25%, total dust almost completely and SOx by around 25% after the fuel switch. Heavy metal emissions are eliminated entirely.
• Replacing the coal power plant with the new CCGT plant thus plays an important role in achieving climate change mitigation goals and improving air quality in the area around the power plant site.
• Following the construction of the CCGT plant on the Altbach/Deizisau site and the decommissioning of the coal blocks, the existing coal storage facility will no longer be needed, thereby completely eliminating its dust and noise emissions. .
• The new plants will reduce the volume of traffic, because coal will no longer need to be supplied after the decommissioning process and the disposal of residues and delivery of additives linked to flue gas cleaning will no longer be necessary.
• Once the new plant has been built, the coal boilers, the associated flue gas cleaning system and the coal-fired auxiliary steam generators will be decommissioned. This eliminates noise sources that were significantly louder than the new plants will be with their modern noise reduction technology.