黑料视频

Offshore wind turbines often produce more electricity than can be transported onshore via the power lines. If the electricity cannot be purchased, they stand idle. It would be more efficient to convert the electricity directly into the storable medium hydrogen. Producing hydrogen from seawater directly where the wind blows - this idea is the focus of the SalYsAse project (saltwater electrolysis using marine bacteria on titanium gas diffusion layers). The principle: electricity is to be converted into so-called green hydrogen by means of electrolysis. During electrolysis, water is separated into its components, hydrogen and oxygen, using an electric current. Green hydrogen is CO₂-neutral and can be easily stored and transported. The project is being funded by the Federal Ministry of Research, Technology and Space with 733,000 euros over three years.

"The aim of the project is to produce hydrogen using saltwater electrolysis in an environmentally friendly and cost-effective way - but with optimised efficiency and less use of chemical catalysts,鈥� says Dr Mirjam Perner. She is Professor of Geomicrobiology at 黑料视频 Helmholtz Centre for Ocean Research Kiel and is leading the project together with Prof. Dr Jana Schloesser, Professor of Materials Engineering at Kiel University of Applied Sciences, and Florian Gerdts, lead process engineer at the Kiel-based technology company Element22.

Challenges of electrolysis with salt water

Up to now, electrolysis has required purified fresh water, as it contains neither salts nor minerals and therefore protects the electrolysis system from corrosion. However, only 2.5 per cent of the world's water reserves are fresh water. Furthermore, the desalination and purification of salt water causes additional costs that could be avoided by utilising seawater directly. As part of the SalYsAse project, the scientists want to utilise salt water directly from the sea. This presents them with a number of challenges: The salt it contains can produce toxic chlorine gas during the electrolysis of seawater. "Faster corrosion of the electrodes or undesirable side reactions can also occur. We want to prevent this by using suitable materials in combination with the microorganisms," says materials expert Jana Schloesser.

Efficient catalysts and membranes

In order to be able to utilise the seawater, the researchers want to use marine microbes, i.e. bacteria, in addition to conventional catalyst layers. The microbes come from the Baltic and North Sea, as they are best adapted to the conditions of salt water. Mirjam Perner explains: "The chemical element iridium is often used as a catalyst as it is very resistant to corrosion. However, it is rare and therefore only available in limited quantities. That's why we want to use biocatalysts in the form of microbes." The microbes should help to reduce or even circumvent the challenges posed by the use of salt water.

The project team is also using suitable materials for the membrane, which separates hydrogen and oxygen during electrolysis, and the porous transport layer. "The special feature of SalYsAse is that the porous transport layer not only conducts the current and the reaction media. We design it in such a way that this layer also acts as a carrier for the microbes. This means that biological catalysis takes place directly in the electrolysis cell - an exciting approach that brings together materials science and life sciences," says Florian Gerdts. The project participants want to use porous titanium structures for this, as titanium is particularly resistant to corrosion, which is essential for use in seawater.

In future, the entire process is to take place where the electricity is already generated: at offshore wind turbines. In this way, the scientists avoid having to transport the electricity to the mainland first. This route is expensive and energy is lost. Instead, clean, climate-neutral hydrogen is produced on site. This can be transported onwards efficiently and used in energy-intensive industries such as steel and chemical production, for example.

Background: Hydrogen as the energy source of the future

In order to replace fossil fuels, more renewable energies will be used in the future and sustainable energy sources will be required. Hydrogen plays an important role in this context, as it can be easily stored and transported. Hydrogen as an energy carrier thus enables the coupling of various sectors - from industry and mobility to energy supply.  Green hydrogen is particularly efficient and conserves resources. Hydrogen is considered green if it is produced by electrolysis using electricity from renewable sources such as solar or wind energy. This process does not produce any greenhouse gases. Hydrogen produced by seawater electrolysis at windy locations can be used in industry or heavy goods transport, for example.

Funding:

The Federal Ministry of Research, Technology and Space (BMFTR) is funding the project with a total of 733,000 euros over a period of three years.

Partners:

The project partners are Kiel University of Applied Sciences, coordinated by the Kiel University of Applied Sciences Research and Development Centre GmbH, and the technology company Element22 GmbH from Kiel, which manufactures the titanium components for this project. SalYsAse is linked to CAPTN Energy, an innovation alliance in Schleswig-Holstein that utilises renewable energies for maritime applications.