Could old pipes power EU’s green dreams?

Green transition 17 August 2022 Per Jørgensen Geir Agustsson

There are few shortcuts in the green energy transition. But for hydrogen, an opportunity has emerged to piggyback off existing fossil fuel infrastructure.

5 mins

Europeans consumed 507 billion cubic metres of natural gas in 2020. If you stacked that gas in one column, it would be one kilometre across and 507 kilometres tall – reaching higher than the International Space Station.  

This gas is primarily transported by pipelines, which could become obsolete as Europe weans itself of fossil fuels. But now, infrastructure owners across the continent are promoting plans to give the pipes a new, green lease of life as Europe’s ‘hydrogen backbone.’   

Recent studies from Ramboll lend credibility to this idea. Results show it is technically and economically feasible to retrofit old pipes to transport hydrogen, and thereby accelerate the green energy transition.  

“Retrofitting only costs 20-30% of building new pipelines, although that is highly dependent on specific conditions and operational scenarios. Nevertheless, this makes retrofitting a really attractive option,” says Geir Agustsson, Lead Pipeline Engineer at Ramboll.  

“For new hydrogen pipelines, one of the most exciting things we have found so far is that increasing the capacity from 2 GW to 10 GW is likely only to increase total costs by 20%. This is good news, because scale is needed,” he adds.  

Off to sea

In late May, some of Europe’s most senior political leaders visited the Danish port city of Esbjerg.  

Once a major fishing port, the industrial city on Denmark’s windy west coast has since rebranded as the country’s Energy Metropolis and become a key staging ground, first for offshore oil and gas, and in the past decades for the deployment of offshore wind in the North Sea.  

“Results show it is technically and economically feasible to retrofit old pipes to transport hydrogen, and thereby accelerate the green energy transition”

The leaders of Denmark, Germany, the Netherlands, Belgium and EU Commission President von der Leyen announced plans to develop the North Sea as a “Green Power Plant of Europe” by scaling offshore wind capacity to at least 150 GW by 2050, and scaling green hydrogen production to 20 GW by 2030.  

Germany is expected to be a major offtaker of this hydrogen. In its 2020 hydrogen strategy, the German Government outlines a need for imports as it predicts it will only be able meet 12-15.5% of hydrogen demand by 2030 through domestic production.  

Meeting demand 

With little doubt about the demand, a bigger question is whether exporters will be able to meet it.  

“The key question remains how fast we scale hydrogen production,” says Per Jørgensen, Head of Gas Infrastructure at Ramboll.  

He points out that countries in the North Sea region will first look to satisfy domestic demand, and only begin exporting once there is a surplus. Initially, that might not require large overhauls of the existing pipeline infrastructure, as some hydrogen can be mixed into the existing natural gas supply or used close to production.  

“The most lucrative place to produce hydrogen right now is in the north of Sweden or Norway because the price of electricity there is low”

“There is no clear consensus yet how much hydrogen can be mixed into the existing gas supply, with estimates ranging from 5-20%,” Per Jørgensen explains, adding that hydrogen production is unlikely to exceed this limit by 2030. 

Pipelines are like highways

So why bother with pipeline infrastructure today, if the current system can tide us over until 2030? 

First and foremost, it is a matter of resolving three as-yet unanswered questions before they slow down the green transition:

  1. How should hydrogen pipelines be designed?
    Pipelines for natural gas have been around for more than 100 years, but so far there has been too little research and testing of hydrogen pipes. Experts say current design norms are too conservative.

    “Fundamentally, hydrogen pipelines are not different from those used for natural gas, but some material aspects need to be considered. We need to study how to minimise leakage, as the hydrogen molecule is much smaller than natural gas, which primarily consists of methane. If we don’t challenge existing design codes, it will also reduce the usability of existing pipelines considerably,” Geir Agustsson explains.

  2. Where will the green hydrogen be produced?
    The answer to this question will be determined by where electricity is cheapest. “The most lucrative place to produce hydrogen right now is in the north of Sweden or Norway because the price of electricity there is low” “In that case, new pipelines would be needed to connect with offtakers, for instance in the Swedish steel industry, which has ambitions to produce net zero carbon steel,” Per Jørgensen says.

    These new pipeline connections would also help advance the knowledge needed to update existing design norms. “With the new plans for additional wind and solar in North-West Europe, hydrogen can be produced when there is surplus electricity production. Further, hydrogen can be produced in North Africa and exported via pipelines to the EU,” he adds.

  3. Are the pipes free when you need them?
    Pipelines are like highways. They can get congested, and it’s generally not a good idea to put cyclists, pedestrians, and cars in the same lane. Similarly, in the world of energy, hydrogen might compete with biogas – which has seen a rapid increase in production in recent years for pipeline access.

    “Biogas is a dark horse,” Per Jørgensen explains, as some countries are betting big on it while others expect to rely on natural gas for the foreseeable future. “As a short-term solution, hydrogen can be mixed with biogas to a certain extent. But in the long run, we will probably get two parallel systems with one being dedicated to hydrogen,” he adds.

Some of these questions are being tackled right now at the EU level. A new proposal in the EU parliament, expected to pass later this year, establishes how much hydrogen can be blended into the natural gas mix, who has access to the pipelines, and who ultimately pays for and maintains them.

Connecting the dots in Europe’s hydrogen network

One of the boldest visions for hydrogen infrastructure is the European Hydrogen Backbone, an initiative pioneered by infrastructure owners from 28 European countries. They aim to establish a 50,000-kilometre hydrogen network across the continent by 2040, consisting of 75% converted natural gas pipelines connected by 25% new pipeline stretches.

According to their estimates, this would require investments of between EUR 80-143 billion. A hefty price tag, but Europe’s transmission service operators expect this infrastructure could adequately transport all of Europe’s domestic hydrogen production, connecting green power hubs with industrial clusters – decarbonising sectors of the economy that are not easily electrified.

What will Europe’s hydrogen infrastructure look like in 2040? Explore this detailed interactive map by the European Hydrogen Backbone to see the plans for yourself.

 To contact the editor of this article email Anders Brønd Christensen, Content Advisor, Ramboll

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