Analysis of operating conditions and NOx-emissions of Tier III ships. Engine load and NOx-performance in Dutch sea and port areas
report
Despite overall reductions in transport-related NOₓ-emissions, maritime sources remain a concern for the Netherlands, particularly in Dutch coastal waters and major port areas. While NOₓ-emissions from the road transport sector show a downward trend, reductions from shipping activities are less pronounced. Commissioned by the Ministry of Infrastructure and Water Management, this study by TNO combines quantitative analysis of shipping operation and NOₓ-emissions with qualitative insights from stakeholders to assess the real-world effectiveness of the latest IMO Tier III nitrogen oxide (NOₓ)-emission standard for maritime engines. The focus is on comparing actual operating loads of marine diesel engines used for ship propulsion with the certification loads under Annex VI Regulation 13 (Tier III) NOx-limits. Several sources report that these engines often run below 25% engine load—the lowest load considered in the test cycles for certification of engines for the main propulsion. At these low loads, low NOₓ-emissions aren’t guaranteed . Using AIS-derived sailing profiles, the study quantified low-load operation shares and estimated the proportion of NOx emitted at low load in the total NOₓ-emissions for Tier III ships in the sea and seaport areas of the Netherlands1 . These effects are also assessed by ship type, size and different areas to identify where the impact is the biggest.
Topics
TNO Identifier
1021020
Publisher
TNO
Collation
36 p.
Place of publication
Den Haag