The challenge
A 20 MW green-hydrogen facility ran its electrolyzer stacks, rectifiers and drying rooms almost continuously, rejecting a steady low-grade heat load. At the same time it needed to pre-heat deionized-water feed and warm the control building - bought separately as energy.
The solution
Air-to-air sensible plate cores recovered heat from ventilation and compressor-room exhaust to pre-condition incoming air and pre-warm the water feed. A solid partition kept the two streams isolated, which matters in an environment where trace hydrogen or alkaline mist must never cross into occupied or process air.
The result
Auxiliary energy fell by roughly 18 percent - meaningful because electricity for electrolysis is the dominant cost of green hydrogen. The static cores also needed almost no maintenance versus rotating alternatives.
Why plate, not wheel
The isolation requirement ruled out any device with stream carry-over. A separated sensible plate was the only compliant choice, mirroring the data-center free-cooling retrofit logic of contamination-free recovery.