Green Hydrogen: Europe’s Pipeline Infrastructure

Germany recently took a historic step in renewable energy engineering by officially approving the plans for a national hydrogen core network, known as the “Kernnetz.” This massive infrastructure project aims to decarbonize Europe’s largest economy by replacing fossil fuels with hydrogen in heavy industry. This article details the specific scope, cost, and timeline of this engineering feat.

Germany's Hydrogen Core Network (Kernnetz)

In October 2024, Germany’s Federal Network Agency (Bundesnetzagentur) formally approved the proposal for the hydrogen core network. This decision gives the green light to transmission system operators to begin construction and conversion immediately.

The scale of this project is unprecedented in European energy history. The approved network covers a total length of 9,040 kilometers (approximately 5,617 miles). The goal is to connect hydrogen production sites and import harbors directly to high-demand industrial consumers.

The infrastructure strategy relies heavily on recycling existing assets rather than building everything from scratch.

• 60% Converted Lines: Approximately 60% of the network will consist of existing natural gas pipelines that are repurposed for hydrogen transport.
• 40% New Construction: The remaining portion will require newly laid pipelines to bridge gaps in the grid.

The Timeline and Investment

The timeline for this project is aggressive. The network is scheduled to be fully operational by 2032. This target date aligns with Germany’s broader climate goals to reach climate neutrality by 2045.

The investment volume for the Kernnetz is estimated at €18.9 billion. This capital will come primarily from private investors and grid operators, supported by a state-backed financing model. To keep user fees affordable during the initial ramp-up phase (when there are fewer users), the government has implemented an “amortization account.” This mechanism caps the grid fees for early users, smoothing out the costs over several decades until 2055.

Connecting Supply and Demand

The engineering logic behind the pipeline is to link supply sources with consumption centers. The network is designed with a “feed-in” capacity of 101 gigawatts (GW) and an “exit” capacity of 87 GW.

Where the Hydrogen Comes From

Germany acknowledges it cannot produce enough green hydrogen domestically to meet its needs. Therefore, the pipeline infrastructure focuses heavily on import points and domestic generation:

1. Import Terminals: Pipelines will connect to LNG and hydrogen terminals in the north, such as Wilhelmshaven and Brunsbüttel.
2. Offshore Wind: Connections to coastal areas will allow hydrogen produced via offshore wind energy to enter the grid.
3. Cross-Border Links: The network includes 13 border crossing points to facilitate imports from neighbors like Denmark, Norway, and the Netherlands.

Who Needs the Hydrogen?

The primary customers for this network are not residential homes, but energy-intensive industries that cannot easily run on electricity alone. The pipeline route is specifically drawn to serve major industrial belts:

• Steel Manufacturing: Companies like ThyssenKrupp and Salzgitter AG require hydrogen to replace coal in the steel-making process (direct reduction).
• Chemical Industry: Giants like BASF in Ludwigshafen use hydrogen as a basic feedstock for ammonia and other chemicals.
• Power Plants: Gas-fired power plants that are “hydrogen-ready” will use the fuel to generate electricity during periods when wind and solar output is low.

Integration into the European Hydrogen Backbone

Germany’s Kernnetz is the central piece of a larger puzzle called the European Hydrogen Backbone (EHB). The EHB initiative aims to create a pan-European hydrogen market.

Because of its central geographic location, Germany acts as a transit hub. The pipeline will allow hydrogen produced in the windy North Sea or the sunny Iberian Peninsula to travel to industrial centers across the continent. For example, pipelines from Norway (a major supplier of gas and soon low-carbon hydrogen) will feed directly into the German grid.

This interconnectedness provides security of supply. If domestic production dips, the grid allows for imports from multiple directions. The 2032 completion date for the German core network is a critical milestone for the wider European energy union.

Technical Challenges of Repurposing Pipelines

Converting natural gas pipelines to carry hydrogen is efficient, but it presents specific engineering challenges. Operators cannot simply pump hydrogen into existing steel tubes without preparation.

Hydrogen Embrittlement Hydrogen atoms are the smallest in the universe. They can diffuse into the crystal structure of steel, causing it to become brittle and crack under pressure. Engineers must inspect existing pipes to ensure the steel grade is compatible. In some cases, internal coatings or lower operating pressures are required to ensure safety.

Leakage and Compression Hydrogen is much less dense than natural gas. To transport the same amount of energy, the gas must be moved at higher speeds or pressures. This requires different compression technology. Compressors designed for methane generally cannot handle pure hydrogen efficiently. The €18.9 billion budget includes significant funds for retrofitting compressor stations to handle the unique flow characteristics of hydrogen.

Frequently Asked Questions

Who is paying for the German hydrogen pipeline? The pipeline is financed by private transmission system operators (TSOs). However, the German government provides a financial guarantee through an amortization account. This allows operators to cap fees for early users and recover their investment over a longer period (until 2055).

When will the network be finished? The target for the complete core network (Kernnetz) is 2032. However, sections of the grid will come online earlier as they are converted or constructed.

Can natural gas pipes really be used for hydrogen? Yes. Studies by the pipeline industry indicate that a large percentage of the existing steel infrastructure is suitable for hydrogen transport. Operators must check steel grades and potentially replace valves, seals, and compressors, but the pipes themselves are often compatible.

What is the difference between the “Kernnetz” and the distribution grid? The Kernnetz is the “hydrogen highway” (transmission level) that moves large volumes across the country. Local distribution grids (the smaller roads) will branch off from this core network to reach specific factories or municipal utilities, though widespread residential use is not the primary focus.