Since MRI is very sensitive regarding electromagnetic disturbances, the integration of a Positron Emission Tomography (PET) detector into in an MRI system is a sophisticated task. The power supply and cabling of the PET detectors are the main sources of electromagnetic interferences with the MRI. Therefore, we propose to power the PET detectors with a proton-exchange membrane fuel cell (PEMFC). To prove the feasibility of the concept, we evaluated the MRI compatibility of the PEMFC. The PEMFC was able to power PET detectors and only a minor influence of the PEMFC on the B0 homogeneity and noise level was measured.