Evaluating the Efficiency of Power-to-X Technologies by adapting the VDI-Guideline 4663

The utilization and conversion of fossil energy sources can be identified as a main reason for greenhouse gas emission. Renewable energy will show a great potential to reduce the need of fossil energy sources, especially if it is combined with Power-to-X technologies. To allow a targeted optimization, the VDI-Guideline 4663 proposes a new method, the Physical Optimum (PhO), to evaluate the efficiency of a process. The basic challenge of this method is the development of an ideal reference process. This work applies the Physical Optimum on a Power-to-X system and evaluates a component of the system. The paper discusses: - The method of the Physical Optimum and the resulting PhO-Factor in general - The implementation of the VDI-Guideline 4663 on complex industrial processes as an indicator of efficiency - Power-to-X technologies in general and suitable system boundaries for an implementation on Power-to-X systems - The implementation of the VDI-Guideline 4663 on a heat exchanger as an indicator of efficiency