Fraunhofer IKTS: SOEC/SOFC Technology Fraunhofer IKTS has developed its CFY stack technology, which can be operated reversibly in solid oxide electrolyzer (SOEC) or fuel cell (SOFC) mode. The institute has formed a partnership with thyssenkrupp nucera, a large electrolyzer OEM, to commercialize and mass produce the technology. Fraunhofer IKTS: SOEC/SOFC Technology