In the heart of Berlin, a visionary group of German solar pioneers founded STOFF2 in 2020, embarking on an ambitious mission to redefine the green hydrogen production landscape. Their creation, the Zinc-Intermediate Electrolyser (ZZE), stands as a testament to their innovative spirit, ingeniously merging the capabilities of a battery and an electrolyser into one groundbreaking, cost-effective device. This hybrid marvel has not only carved out a new niche in the market but has also set sectors on a steadfast course towards a 1.5°C decarbonisation pathway, offering secure, affordable, and sustainable green hydrogen.

The masterminds behind STOFF2, Andrew Zwinkels and Alexander Voigt, bring over two decades of expertise in the energy and solar industry to the table. Their shared vision and experience have been pivotal in steering the company towards its goal of achieving 100% renewable energy across all sectors.

The ZZE, the cornerstone of their innovation, offers a time-decoupled approach to renewable energy intake and green hydrogen production, granting customers unparalleled flexibility and significant cost savings.

The brilliance of the ZZE is encapsulated in its three-phase operation. It strategically capitalises on the most affordable hours of solar and wind power to minimise operational costs. Energy is then stored as solid metal zinc, a safe and efficient intermediate that can hold the charge from minutes to days. Upon discharging, the ZZE consistently produces hydrogen for 12 to 24 hours, boasting a capacity of 1 MWh per cycle within a single 20-foot container. Remarkably, the technology forgoes the need for PFAS, platinum, cobalt, or lithium, relying instead on zinc—a material that is not only readily available but also economically producible.

The journey of the ZZE from concept to reality unfolded at the former Berlin Tegel airport, where STOFF2 developed its prototype. The technology’s first significant trial will take place in Alkmaar, Netherlands, as part of the €20 million EU-funded REFORMERS project, which aims to establish “Renewable Energy Valleys.” As a key partner among 28 industry and research organizations, STOFF2 is set to deliver a 2 MWh ZZE, demonstrating its substantial contribution to the energy system.

With the first production facility underway in Berlin, STOFF2 is gearing up to commence deliveries of the ZZE to its initial customers in 2026. The subsequent year, 2027, marks a pivotal moment for the company as it plans an industrial scale-up in Germany, in collaboration with strategic partners.

STOFF2’s journey is not just about technological advancement; it’s a bold stride towards a sustainable future, powered by green hydrogen and renewable energies. The company’s vision and innovative solutions are paving the way for a cleaner, greener world, one electrolyser at a time.

In the pursuit of a sustainable future, STOFF2’s Zinc Zwischenschritt Electrolyser (ZZE) emerges as a game-changer in the production of green hydrogen. This innovative system harnesses renewable energy sources like solar and wind power during peak production times, enabling the cost-effective generation of hydrogen. Here’s how STOFF2’s ZZE is setting new standards in the energy sector:

Cost-Effective Green Hydrogen Production
The ZZE utilizes renewable energy when it’s most abundant and least expensive, significantly reducing the cost of hydrogen production. This strategic use of energy ensures that green hydrogen is not only sustainable but also economically viable.

Innovative Energy Storage and Electrolysis
With its hybrid functionality, the ZZE combines energy storage and electrolysis, making it RED II-compliant and simplifying technical complexity. This dual capability allows for seamless integration into existing electricity and gas networks, enhancing the system’s efficiency and reliability.

On-Demand Hydrogen Production
The ZZE’s design decouples the timing of power intake from hydrogen production, providing the flexibility to produce hydrogen on demand. This feature also enables the utilisation of renewable energies that would otherwise be curtailed, optimising energy use and reducing waste.

Resource-Efficient and Safe Technology
STOFF2’s commitment to sustainability is evident in its choice of materials. The ZZE eschews the need for rare and expensive elements like PFAS, platinum, cobalt, or lithium, instead using zinc—a safe, widely available, and inexpensive resource. The energy is stored as solid metal, conserving resources and ensuring safety.

Reliable Hydrogen Delivery
When it’s time to discharge, the ZZE reliably converts the energy stored in the zinc layer into hydrogen. This process also generates electricity and heat, adding to the system’s efficiency. The asynchronous charge-storage-discharge cycle can be tailored to specific needs, offering unparalleled adaptability.

STOFF2’s Zinc Zwischenschritt Electrolyser is not just an electrolyser; it’s a beacon of innovation in the green energy landscape. By prioritizing cost-effectiveness, ease of integration, on-demand production, resource efficiency, and reliability, STOFF2 is leading the charge towards a cleaner, more sustainable energy future—one zinc layer at a time. •