High Temperature Superconducting (HTS) power cables are being developed for specific low and medium voltage applications that need to support large and variable load currents. Developments of HTS cables for electric ship applications with integrated medium voltage direct current (MVDC) power systems are discussed. The electrical and cryogenic thermal design challenges and the potential solutions for HTS power cables are discussed. This paper includes a section about recent developments in helium gas cooled HTS cable designs in terms of gaseous media and dielectric strength as well as new cable design options.