Seasonal Storage System: the compressor
The Seasonal Storage System (flagship project of the 24/7 Energy Hub programme) allows us to produce hydrogen on a daily basis. One of the key components within the system is the compressor, delivered by HyET Hydrogen. This resulted in a fruitful cooperation. Joel Bosrup (Wintersol) and Leonard Raymakers (HyET Hydrogen) look back on the process and share what they have learnt along the way.
Joel founded his company Wintersol in 2019 with the idea of building local storage and dispersion of renewable energy to make buildings energy self-sufficient, using locally generated renewable energy. He learnt about The Green Village through HyET Hydrogen, the producer of the compressor. HyET Hydrogen is focused on compressing hydrogen efficiently, with a new technology that has not been applied in the field before. The technology also works for purifying hydrogen. HyET sees a lot of potential in smaller energy storage systems, in which their compressor could play an important role.
Seasonal Storage System
Like the engine of a car
The role of the compressor is to reduce the space needed within the 24/7 system. It literally compresses hydrogen to fit in the cylinders. Joel: “In that sense, it’s a key component. The cylinders take up quite some space already. Without the compressor, we would need ten times as much capacity, making it less feasible to store this amount of hydrogen.”
It has been Joel’s job to integrate the compressor into the Seasonal Storage System. But this was far from plug-and-play: “The compressor can be compared to the engine of a car,’ according to Joel. The car around it still had to be built. The compressor stack is the building block that performs the actual compression: Low-pressure hydrogen is applied on one side and high-pressure hydrogen comes out on the other. I have been integrating the system to support this. By adding a cooling element for when the stack is working and generates heat for example. And I have implemented all sorts of valves, humidification and safety mechanisms on both the hydrogen inlet side and the outlet side for protection against overpressure. Close cooperation with HyET Hydrogen was essential to get it up and running.”
The compressor
Lessons learnt
This is the first time that a ready-built HyET compressor has been adapted to a specific environment, which makes the project quite unique. Leonard explains: “HyET can benefit from the bottlenecks that Joel encounters, especially on the operational side. There were questions like: how would such a system powered with PV panels, first charge a battery and then start the electrolyser? Joel did a really great job at modelling that, properly designing the system and sizing it correctly. Field data on an actual system is crucial for the continuous improvement of our products.”
“Everything was new and a first”, Joel adds. “We have had many long sessions surrounding safety evaluations. It may seem tedious, but afterwards, you’re really happy that you’ve done it. Now we can feel confident because we know it’s safe. And the trust that HyET instilled in me has been heart-warming. They’ve invested a lot of hours in this project, for which I’m very grateful.”
Joel Bosrup & Leonard Raymakers
Testing at The Green Village
HyET is very excited to see the results of testing at The Green Village: “We see an increasing demand for our compressor in this specific application. That wasn’t even on our radar a few years ago. The information and data that The Green Village has to offer are very valuable for future projects.”
And that’s not the only thing The Green Village provides, according to Leonard. ‘The Green Village is a very well-known test location in the Netherlands within the hydrogen space. The fact that the HyET compressor is part of this certainly helps to show that our technology is working.”
Read more about 24/7 Energy Hub.
Technique behind the HyET compressor
For the compressor, a proton conductive membrane is used. It’s a very thin, polymer sheet with a platinum catalyst applied on both sides,. When hydrogen is offered to the membrane, it travels from one side of the membrane to the other side via an electrical current. It cannot go back through the membrane. The membrane itself doesn’t move, so there is no friction. Ultimately, you get an increasingly amount of hydrogen on the other side of the membrane. When you close that volume, by connecting the compressor to a buffer tank, the buffer tank slowly fills up. The pressure increases and can go up to 500 bar. In the 24/7 project, we are going up to 300 bar. The absence of moving parts makes this compressor a silent, simple and sturdy principle.
