A brand-new life cycle assessment study initiated by NCE Maritime CleanTech estimates and compares the life cycle GHG emissions of a range of propulsion system technologies through three case studies.

Norway has committed to reducing its greenhouse gas (GHG) emissions. Both national and international goals have been set for emission reductions for the maritime sector. The development and adoption of new and emerging marine fuels and energy carriers may offer GHG emission reduction potentials for the Norwegian ocean industry, but because emissions arise both upstream and downstream of the use phase, a life cycle perspective is required to obtain a complete picture of the GHG emissions. Addressing this issue, NCE Maritime CleanTech commissioned Asplan Viak AS to do a comparative life cycle assessment (LCA) study of a range of marine propulsion systems relying on different fuels and energy carriers.

This report estimates and compares the life cycle GHG emissions of a range of propulsion system technologies. Through three case studies, various propulsion systems for a platform supply vessel, a chemical tanker, and an express boat are considered. The study considers both conventional fuels and internal combustion engines as well as new and emerging alternatives such as ammonia as a combustion fuel and electrification through the use of energy carriers in batteries and fuel cells.

From cradle to grave
Two wide categories of propulsion technologies were considered in the three case studies: combustion-based propulsion systems and electric propulsion systems. The cradle-to-grave GHG emissions were calculated for a given number of years of operation and considered the most relevant components as well as fuels and energy carriers.

– This is a very interesting report that first of all illustrates the necessity of evaluating the complete life cycle of new fuels. It also gives good indications of which fuels should be used for supply vessels, tanker vessels and fast ferries to achieve the highest emission reductions, says CEO of NCE Maritime CleanTech, Hege Økland.

Main findings
For new and emerging fuels and energy carriers such as ammonia, biofuels, hydrogen, and electricity, decision makers should carefully evaluate the realistic availability of low-emissions production pathways in the location of the intended vessel operation to ensure GHG benefits. Furthermore, the operational profile and application should also be considered as these may affect suitability from a GHG emission reduction perspective. Failing to account for availability, operational profile, and application, well-intended decisions may result in undesirable outcomes that may increase the overall GHG emissions. The LCA study demonstrates that significant GHG emission reductions may be obtained for marine propulsion systems, and ultimately the transport sector, but its realization and optimization require informed and deliberate decision making. 

Across the different case studies, we find that certain propulsion systems may offer GHG emission benefits for one application and operational profile, but disadvantages in another. The main findings for the considered propulsion system configurations are summarized in the report that is available only for cluster members in NCE Maritime CleanTech.

The preliminary results provide useful insights and highlight important benefits and challenges pertaining to the GHG emissions of various marine propulsion system technologies. The LCA study demonstrates that significant GHG emission reductions may be obtained for marine propulsion systems, and ultimately the transport sector, but its realization and optimization require informed and deliberate decision making.

Exclusively for cluster partners
Recently NCE Maritime CleanTech hosted a webinar together with Asplan Viak. In the webinar, Asplan Viak´s Linda Ager-Wick Ellingsen presented the findings. Cluster partners in NCE Maritime CleanTech can watch a recording of the webinar and read the full report by entering this page (log in required).

More information on membership in NCE Maritime CleanTech here. The work with the report has received financial support from Vestland County Council.