A Life Cycle Cost Analysis of Marine Scrubber Technologies

Abstract

MARPOL Annex VI regulates the emissions from all ships trading internationally. Ship owners must take actions before the lowest limits come into force. The combined challenges of rising oil prices and increasing regulatory stringency on shipping’s air emissions justify the exploration of feasibilities between compliant technologies. This study focuses on the scrubber technology for large marine engines with which ships can continue to use preferable cheap heavy fuel oil (HFO) without exceeding the emission control limits. It draws on existing technical and economical information about scrubber systems in the market to establish a complete life cycle cost analysis for four vessel types: Containership, passenger ship, Ro-Pax and tanker.

An investigation of the technology overview, cost data, emission reduction efficiency, impact of installations, operational issues and installation case studies is conducted. Environmental impacts such as wash water discharge, sludge disposal and end-of-life recycling are also addressed. By choosing the marine gas oil (MGO) utilisation as the baseline, the life cycle cost analysis is performed between different types of scrubber system, namely open loop seawater scrubber, closed loop freshwater scrubber, hybrid scrubber and dry scrubber system.

The life cycle cost analysis results are presented by the net present value (NPV) and the return of investment (ROI) time. Under the assumption of current HFO and MGO price, a positive NPV can be found for every scrubber types subjected to four vessel types with the ROI time ranging from 1to 5 years depending on the operation profile in ECA-SOx.