HEXIS is developing and manufacturing SOFC-based micro-CHP systems for single-family or small multi-family houses. Galileo 1000 N with an output of 1 kW electrical power was brought into the market 2013. Since then, HEXIS together with other members of the Viessmann Group have been developing the next generation of the Viessmann/HEXIS SOFC system.

The paper and presentation will report on the newest results of the short-stack tests, fullscale-stack tests as well as on system tests based on the established Galileo systems as well as on Hexis’ next generation systems. These include results of Galileo tests running for more than 23’000 h, electrical efficiencies of the new generation of 40 % AC, net and total efficiencies of 95 % (LHV). An electrical efficiency of 54 % (DC) was demonstrated on fullscale-stack level with steam reforming.

The tests showed that the electrical efficiency is rather constant in the desired operation window. Degradation rates as low as approx. 0.3 % / kh, i.e. 10 mΩ cm² / kh could be shown on short-stack level over 19’000 h. As a consequence, the next generation will be operating at higher power densities, allowing a higher electrical power output at unchanged stack size. The results of tests concentrating on Redox and on-off cycles will be another topic of the contribution.

HEXIS’ next generation systems are being developed together with other group companies of the Viessmann Group leading to a new system architecture. The contribution will give a first glance into this new architecture and will show first test results obtained.