On the way to a hydrogen economy, Germany needs a huge network of transport pipelines. The fundamental basis for this is the pre-existing gas grid. What could the hydrogen network of the future look like and whom will it connect?
New technologies require new infrastructure. The railroad required a track network, electricity a power grid and mobile telephony a system of masts. Hydrogen will soon be available in large quantities all over Germany. Will the whole country have to be dug up and new pipelines laid?
German gas pipelines are ready for hydrogen
The answer is no – hydrogen is a gas and Germany already has a gas network. According to a recent study, Germany's gas pipelines have the capacity to transport hydrogen. The German Technical and Scientific Association for Gas and Water (DVGW) and gas transport company Open Grid Europe (OGE) conducted a study that puts to rest long-standing concerns that hydrogen could embrittle the steel in the pipelines. Based on these results, the natural gas pipelines are well prepared for the transport of hydrogen. However, further tests need to be carried out, including on regulators and fittings. Just as there are more than just rails in a railway network, there are more than just pipes in a gas network. However, the result is an important foundation for taking the first steps towards conversion.
From the gas grid to the hydrogen grid
The authors estimate a required investment for the upgrade of the current network to be around 30 billion euros. This may sound like a lot of money, but on closer inspection, it is a bargain: The German gas network is more than half a million kilometers long. Building a new pipeline network to transport hydrogen would take many decades and devour hundreds of billions of euros. The existing gas grid therefore offers an opportunity to meet the "transport" challenge on the way to a hydrogen economy – both quickly and comparatively cheaply.
On the way to the hydrogen economy
Does that solve all the challenges? Not yet, because the existing gas network will still be needed for natural gas for many years to come. And in some parts of the country hydrogen is already being added in small quantities. Studies show that many appliances in German households can be operated with up to 30 per cent hydrogen without any problems. A sub-network in Saxony-Anhalt has already added around 20 per cent hydrogen, and a district near Heilbronn is gradually being supplied with up to 30 per cent hydrogen. Furthermore, hydrogen is not just to replace natural gas on "Day X“ but is to be used as soon as possible in a wide variety of places in Germany. This means first in industry, then public transport, power generation and heating. Many future consumers are not yet, or not sufficiently, connected to a possible hydrogen network. It is not only a question of converting the existing network, but also of expanding it to meet demand.
New pipelines for new customers
The German steel industry shows why this is necessary. It is responsible for a third of all CO2 emissions from German industry. To reduce these emissions and remain competitive, steelmakers are planning to switch from coal to hydrogen. The high CO2 emissions give an idea of the enormous amount of energy needed to produce steel. The capacity of the hydrogen infrastructure will have to be correspondingly large to supply these customers – something that today's gas grid is not yet able to do. Moreover, the gas grid will be needed in many places for a long time to come. In practice, the gas and hydrogen networks would have to operate parallel to one another during the transition period.
First hydrogen network by 2030
The major Transmission System Operators (TSOs) have joined forces to gradually build a separate hydrogen network of more than 5,000 kilometers by 2030. For the most part, the operators are using existing pipelines and, in some cases, building new ones. This network will connect major consumers such as refineries, the chemical industry, and steelworks. Underground hydrogen storage facilities are also planned to correspond with supply and demand. By making the hydrogen economy a reality first among large consumers such as industry, this technology is taking a huge first step. But other consumers are also showing high interest, such as municipal utilities that want to use it to run thermal power plants – or transport companies that could refuel trucks at hydrogen refueling stations.
First large consumers, then private consumers
The hydrogen economy will therefore first reach the large consumers – the anchor customers – directly and with large quantities of hydrogen. This is because the investment security is much higher, and the infrastructure is easier to develop. Since complex pipeline networks do not have to be converted first, as is the case with private consumers. Hydrogen is also an important alternative to battery electric drive systems, particularly in the transport sector. The German government expects hydrogen to play a particularly important role in vehicles transporting heavy goods, in aviation and in shipping. Ultimately, the large consumers could be the driving force behind the widespread availability of hydrogen for private use.