12. August 2022 By Zoe Holdt, Julius Glaser and Rabab Bettache
Technical hurdles for the use of hydrogen technologies in Germany
As a ‘green’ energy source, hydrogen is a hot topic at the moment. In our previous blog posts, we provided information on the opportunities and potential that come with the use of the climate-friendly gas. But what are the technical challenges associated with the use of hydrogen and how can they be overcome? We will be taking a closer look at four of them today:
How should hydrogen be stored?
One of the first and most basic challenges concerns the storage of hydrogen, because it has a low volumetric energy density compared to other fuels. In other words, it takes a lot of space to store a small amount of energy. Under normal conditions, for example, a litre of gaseous hydrogen contains only 0.75 kilowatt hours (kWh) of energy. By comparison, a litre of gasoline or diesel is able to store more than ten times that amount. Even in liquid state, a litre of liquefied hydrogen (LH2) can only store about a quarter of the energy that a litre of diesel can. In addition to that, LH2 must be cooled to -253°C in order to remain in a liquid state.
To achieve the same volumetric energy density as natural gas, either a higher compression or three times the volume of hydrogen will be needed. Beyond that, hydrogen diffuses through many materials, placing greater strain on conventional gas tanks and pipelines.
Possible solutions to this issue include the use of special materials in the storage media and, above all else, constant monitoring.
How can hydrogen be safety stored and transported?
Other safety-related challenges associated with hydrogen during transport and storage include its combustibility and the formation of explosive gas mixtures, which have the potential to explode if the hydrogen mixes with pure oxygen (or air). As a result, stricter safety precautions for the storage and transport of hydrogen are of critical importance in order to ensure the safe use of the gas.
The storage of gases under high pressure also presents a potential hazard, which is why the pressure vessels, every screw joint and every single valve must be inspected on an ongoing basis to prevent potential gas leaks or depressurisation in enclosed spaces.
Although safety concepts like this are simple to implement from a technical perspective, they are generally expensive and labour-intensive.
How do you create the infrastructure required for hydrogen?
Other technical hurdles associated with the use of hydrogen technologies include infrastructure issues. One of the main issues concerns the development and expansion of a large-scale hydrogen transmission grid to enable huge quantities of the gas to be transported effectively and efficiently. However, the pipeline-based transmission of hydrogen, especially over longer distances, is technically challenging and energy-intensive because pumps and safety systems require a large and constant supply of electricity.
At the moment, alternative transport routes, such as by tanker truck, are still far more inefficient since, on average, they consume more energy than is contained in the hydrogen they are delivering. Plus, having a very large number of hydrogen-powered lorries on the road also creates traffic and congestion. There are logistical issues relating to the refuelling of hydrogen-powered vehicles. For instance, the hydrogen gas for lorries and cars must be supplied at different pressure levels.
One possible solution that could work would be to transport hydrogen in existing natural gas pipelines. However, special conditions must be created to compensate for the chemical differences between natural gas and hydrogen and prevent the pipeline from being damaged and rendered unusable.
Do we have sufficient power available to produce hydrogen?
Electricity from renewables and hydropower are some of the key inputs needed to produce green hydrogen. However, growing demand for green energy is seen as a challenge. In 2030, demand for hydrogen will reach up to 110 terawatt-hours (TWh), which is nearly eight times higher than domestic production capacity in Germany. To meet this demand, the expansion of environmentally friendly generation capacities and the building of electrolysers will be needed. Along with that, green hydrogen will have to be imported from abroad. The former will also involve changes on a societal level.
Eighty TWh of hydrogen alone will be required to decarbonise the German steel industry.
However, adding more electrolysers will not solve the problem since producing the hydrogen needed to decarbonise the steel industry would consume all the electricity that can currently be generated by all onshore wind turbines combined. Existing and planned wind and solar power plants will therefore not be able to meet demand.
As a result, the short-term solution is to meet at least part of the demand for hydrogen through imports. However, it will also be necessary to consider sustainability to ensure that hydrogen remains a ‘green’ energy source.
What steps are required going forward?
Innovation and investments are needed to successfully create a future built around hydrogen.
We have to expand and upgrade generation and storage capacity, build and expand transmission grids and deploy the accompanying technology to ensure that the gas is processed as efficiently as possible. Safety inspections will be needed in all areas. Along with that, we need to enter into international partnerships for the production and import of the climate-friendly gas now in order to be able to trade directly, if necessary.
Regulatory frameworks and well-developed IT structures are required for the distribution and use of hydrogen as well as to monitor these activities within the country. These still need to be developed and defined. The adesso team is there to support and aid in the setup of the IT structures, including platform solutions.
You will find more exciting topics from the adesso world in our latest blog posts.