The use of shoreside power is becoming increasingly popular among ports and terminals seeking to reduce local air pollution emissions. While work to develop internationally-agreed standards for high voltage connections continues, ABS has released a Guide for High Voltage Shore Connection to address key safety concerns as well as design considerations for shipboard installations. “Cold ironing will continue to grow in importance as more ports around the world install facilities to accommodate this alternative source of auxiliary power,” says Yoshi Ozaki, ABS Director of Environmental Technology. “The design criteria provided in this Guide will help to mitigate risk surrounding safety concerns related to the use of high voltage connections.”
Cold ironing is the practice of shutting down a vessel’s generators while in port and using shoreside power to supply electrical loads. The guidance from ABS fills the gap in the absence of universally adopted standards for high voltage connections. Current class Rules address low voltage shore connections which are typically 450V. The new ABS Guide addresses connections of 6.6 kV or 11 kV. Cold ironing using high voltage brings with it a variety of unique safety considerations. One of the more important is the risk of arc flash, an electrical breakdown of the resistance of air. This is often the result of a breakdown of electrical insulation caused by a buildup of conductive dust, dirt and other particles. According to Ozaki, the rapid release of high energy that results from an arc flash is particularly concerning so the reference requirements during their design, installation and operations are paramount.
ABS provides guidance for system design issues such as shore power compatibility, safety grounding, overvoltage protection and safety interlocks as well as operational issues.
Requirements for the equipment design, installation and survey of high voltage shore connection installations are also captured in the Guide. “We address the safety of personnel during the establishment of high voltage shore connections as well as normal operations, the protection of shipboard equipment and the continued operability of the vessel following the loss of the high voltage shore power supply,” says Ozaki. Guidance also takes into account considerations for the ship’s system grounding philosophy.
A class notation for those vessels complying with the requirements and conditions of the Guide is available. The notation HVSC will be listed in the ABS Record.