The issue of storing surplus electricity from renewable energy sources in periods of high production has gained a new dimension and more frequently conventional grid control mechanisms are unable to cope with those challenges.Solid oxide electrolysis offers an efficient and scalable energy storage technology that has the potential not only to contribute in finding solutions for the typical issues of renewable electricity production, but also in developing carbon neutral fuels. A third opportunity is to use the products, including O2, for further chemical synthesis, for example in the pharmaceutical or plastic industry.Electrical energy can be stored in chemical energy by producing molecular hydrogen or syngas. This happens via electrolysis of steam or co-electrolysis of steam and carbon dioxide. Then, these energy carriers can either be used as a buffer for fluctuating energy production and consumption, or used in the transportation sector. The synthetic fuels are potentially carbon neutral, when the electricity comes from renewable energy production.This thesis aims to identify most promising system concepts including all components that are necessary to operate the electrolysis stacks. Furthermore, several electricity storage technologies where taken into comparison, with the goal to investigate the technologys potential for the energy sector. The methodology is mainly based on Matlab simulations, as well as literature review.Three concepts where identified for hydrogen production, reaching electrical to chemical energy conversion efficiencies between 75% and 89%. Based on these results, as well as on literature review a system concept for the co-production of hydrogen and methane got developed.Based on the results of this thesis a 5kWel Proof-of-Concept system was constructed and tested at AVL List GmbH. The measurements were consistent to the simulation results and an overall electrical system conversion efficiency of 80(3)% was demonstrated.