[ heat exchange ]
Optimising cooling solutions for large-scale green hydrogen plants
Selecting the right heat exchange solution is crucial for enhancing energy efficiency and reducing resource consumption . For large-scale green hydrogen plants , a variety of cooling solutions are available – from dry to wet systems , including hybrids that offer a balance between the two , such as Cascade Cooling . Developed by Kelvion , this innovative solution is designed for large-scale green hydrogen plants , optimising both electrical and water consumption .
By Olivier Robert , Global Solutions & Engineering – Hydrogen , with the support of Quentin Baraër , Lead Thermal Engineer for Cascade Cooling , Kelvion
Cooling capacity requirements in largescale green hydrogen plants
In green hydrogen plants , whether using alkaline electrolysers ( AEC ) or proton exchange membrane electrolysers ( PEM ), a liquid is circulated over the electrolyser stack to produce hydrogen and oxygen . This process generates heat that must be effectively managed . However , there are more cooling points in the hydrogen production process . Alternating current ( AC ) is converted to direct current ( DC ), which releases heat . Other key areas include the formed oxygen and hydrogen , which are cooled before further purification . The deeper the gases are cooled , the more water is ‘ knocked out ’ by means of condensation , reducing the size required for the plant ’ s drying section . Further downstream , the hydrogen is compressed , which requires compression interstage and aftercoolers . A closed loop of water or a water / glycol mixture is used to cool the various coolers in the hydrogen production process .
For plants with an electrolyser capacity exceeding 100 MWe , a central cooling system
Fig . 1 . Cascade Cooling principle
16 Hydrogen Tech World | Issue 18 | October 2024