Allowing vessels to switch off their on-board diesel generators during their port stay and connecting them to the port electrical grid, shore-to-ship power allow harbors to reduce their environmental footprint, improving the working, transit, and living condition of citizens in port areas. The ships' power load is seamlessly transferred to the shore-side power supply without disruption to onboard services. Compliance to global IEC/ISO/IEEE standards allow interchangeability of vessels, independently from the port where they are connecting. Shore-to-ship power eliminates all local polluting emissions by vessels and noise generated by auxiliary engines.