Eos – World’s Most Efficient
PEM Electrolyser
Eos – World’s Most Efficient
PEM Electrolyser
Eos – World’s Most Efficient
PEM Electrolyser
10% more efficient @ 47.5 kWh/kg
10% more efficient @ 47.5 kWh/kg
10% more efficient @ 47.5 kWh/kg
Hystar’s patented technology delivers the highest efficiency and safety – producing more hydrogen per unit area than any conventional PEM electrolyser.
Eos, our compact 0.55 MW stack, scales seamlessly from MW to GW projects, giving you maximum operating flexibility with minimal footprint. With higher output, lower material use, and reduced downtime, Hystar cuts your LCOH significantly, driving a real change in the hydrogen economy.
Watch the video below to learn more.
Eos is Hystar’s PEM electrolyser stack — the patented core technology that splits water into hydrogen and oxygen using electricity. It delivers the highest efficiency and safety, producing more hydrogen per unit area than any conventional PEM electrolyser.
Eos is the “core” used inside Hystar’s Vega (containerized solution) and Orion (cluster for large-scale plants).
Eos operates with Hystar’s patented anode ventilation. Different to conventional PEM stacks, purified water is supplied on the cathode side, which frees the anode for ventilation, which further dilutes potential H2 crossover under all operation points. This enables Hystar to significantly reduce the thickness of the membrane, reducing one of the main resistances in the process and therefore significantly increasing the efficiency of the stack.
No, Eos has its water supply on the cathode side and on the anode side it is continuously ventilated. The electrochemical reaction, however, is completely the same like it is in conventional PEM stacks. Oxygen is evolving on the anode and hydrogen on the cathode side.
No, due to the thin membrane, water can diffuse through the membrane and still be split on the anode side even though it is supplied on the cathode side. In addition, the ventilation flow to the anode is humidified, keeping the membrane moist under all conditions.
Eos operates at 47.5 kWh/kg at 100% load, which Hystar states is approximately 10% more efficient than conventional PEM electrolysers.
One Eos stack produces 11.5 kg of hydrogen per hour at its rated capacity of 550 kW.
Yes. Eos is designed as a modular 0.55 MW building block that scales from single-megawatt pilot projects to gigawatt-scale plants by multiplying stacks, without redesigning the core technology.
Eos uses Hystar’s patented anode air feed and cathode water feed design, which dilutes hydrogen crossover into the oxygen stream to reduce explosion risk.
