Credit DBT Inga Haar

©Technology Salon, Leibniz University

Innovation Lab "Sustainable Hydrogen Combustion Concepts" (WaVe)

More than 20 research teams in Lower Saxony are working on solutions for the hydrogen economy. Many of them within the framework of the five innovation labs coordinated by the EFZN.

A contribution to the stronger networking of science and industry was the presentation of the EFZN hydrogen competence paper. The paper is a "performance showcase" of the Hydrogen Lower Saxony Research Alliance, which has been in existence since 2018.

The NWN took the publication as an opportunity to talk to Lars Eichhorn, research associate at the Institute for Technical Combustion and researcher in the WaVe innovation laboratory.

Mr. Eichhorn, you work in one of the five innovation labs in Lower Saxony. What does the WaVe deal with?

Eichhorn: The Innovation Lab is working on sustainable hydrogen combustion concepts (WaVe) in three projects. One project is concerned with hydrogen engines in vehicles. It is investigating which concepts and adapted components can be used to run existing commercial vehicle engines on hydrogen. The second project is investigating how natural gas can be replaced by hydrogen in a gas-fired power plant. In the third project, on which I am personally working, we want to show that hydrogen can be used to provide primary control power in gas and steam power plants. The short-term power increase of a steam turbine required for this is generated with additional process steam, which is the reaction product of hydrogen-oxygen combustion.

Why can't such processes be electrified?

Eichhorn: In this and many other applications, temperature levels beyond 500 degrees Celsius are required. Especially in the production of ceramics, glass, or cement, the heat demand is very high. Here, thermal utilization is significantly more efficient than electrical utilization of hydrogen.

They are trying to make this combustion even more efficient here. How does that work?

Eichhorn: The handling of the very hot hydrogen-oxygen flame, which burns at atmospheric pressure and temperatures above 3000 °C, is particularly demanding. For this purpose, we are developing a burner that can withstand the thermal load and ensure optimum mixing of the gases as well as reliable stabilization of the flame. The focus is on reducing the combustion temperature to a technologically controllable level.

And you do that with water?

Eichhorn: Correct. In many cases, water vapor is used for this, which is added to the combustion; what is challenging is the quantities required. In our research approach, the flame is cooled with liquid water, which is atomized by the oxygen and enters the combustion chamber as a water-oxygen spray. Within the combustion chamber, the mixing and oxidation of the hydrogen takes place. In initial tests with the new burner, the flame temperature was reduced to below 2000 °C thanks to the innovative concept. Other advantages of using liquid water are the smaller pipe cross-sections in the supply line compared with vaporized water and the fact that no primary energy is required to produce steam. This makes this technology much more flexible and quicker to use.

But steam can already be produced relatively quickly. Where do we need this time flexibility?  

Eichhorn: The aim of primary control power is to provide additional power within seconds to ensure the stability of the power grid. Starting up a steam generator takes too long and is therefore not suitable. Instead, our research approach uses liquid water - without further preparation.

You also work in a basic research laboratory at the Hydrogen Campus Hannover. What is being studied here?

Eichhorn: The basic laboratory was primarily created to arouse students' interest in hydrogen in general and in sustainable combustion technology topics in particular. And indeed, although we are experiencing declining attendance at lectures on combustion engines, we are seeing increasing interest on the part of students in hydrogen technologies and alternative fuels. Especially through the lab, we receive some unsolicited applications for our innovative research projects.

Thank you very much, Mr. Eichhorn.