Frank Sonnenschein moderated at Hydrogen Expo North America, Houston TX, which took place on June 25-26th 2025. Ahead of his participation at this year’s event, we spoke to Frank about a topic that could be of great interest to attendees - How hydrogen technology can contribute to grid resilience.

Grid Balancing and Renewable Energy Integration

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‍Q: How do dynamic operation capabilities of PEM fuel cells (PEMFCs) and PEM electrolysers (PEMELs) support grid balancing and renewable energy integration compared to the more static operation of alkaline water electrolysers (AELs)?

Frank Sonnenschein:
The AEL is very good for general turnover from fossil fuel-based energy to more solar and wind-based energy. They are suitable for large scale operations, have relatively good efficiency, and can effectively transfer and store energy. The downside of AEL is that they are in general less agile than PEMELs. AEL usually need significantly more time to start and stop operation. They are great for static, plannable power support, but have issues with unstable power input.

That is why, for support and balancing of the grid, PEMELs are, in my opinion, more relevant. This is because on a windy, sunny day, often more energy by solar and wind is generated than needed. That surplus can feed back into the grid, or as happens in Germany you can pay neighbouring countries like Poland to take this excess energy. In essence Germany pays Poland to take their energy as they have too much on the grid. Instead of getting paid for selling energy, they must pay to sell energy. This is inherently counterproductive.

With PEMELs, you can switch on and off more or less instantly. When the wind is blowing, you switch it on, and within minutes you start producing hydrogen. When the wind stops blowing or sun stops shining, it switches off and stops producing. It is very dynamic in that way and as a result is ideal for rebalancing.

Read the full article here: Dynamic vs. Static: Green Hydrogen Grid Integration Q&A