Within the challenge of sustainability, climate change mitigation and energy supply a promising way of more rational energy conversion is decentralized power generation and the co-production of power and heat. The combination of a solid oxide fuel cell (SOFC) with a gas turbine (GT) in an hybrid system is considered as a promising technology in this context. The process performance is highly influenced by the optimal energy integration satisfying cooling and heating requirements. Therefore, the goal of this project consists in the study of the heat exchange phenomena and of the design of the heat exchanger network.