The Naval Architect Jul/Aug 2020
Based in Denmark, GSF is financed by its 51 members, three of whom feature their vessels as ‘The Retrofit Project’s’ case studies. First, Maersk Tianjin, a medium range (MR) oil/chemical tanker. Second, Hafnia Lise, another MR oil/chemical tanker, and finally DFDS’ Victoria Seaways, a ro-pax vessel built in 2009.
Although the case study partners were selected by GSF, Frederik Schur Riis, Head of GSF, notes that the individual vessels used were chosen by the shipowners themselves, based on each company’s strategic considerations such as fleet composition.
For each vessel studied in the retrofit report, which began in January 2019 and ended April 2020, the respective shipowner applied a customised selection of energy optimising retrofits ranging from BWTS to propulsion upgrades.
Four common areas of significant optimisation potential were identified: Lack of available data, wasted energy consumption due to excessive electricity production and inefficient lighting, benefits of products such as anti-fouling overlooked due to their expense, and finally the application of digital solutions.
For Hafnia, the project’s overall findings are doubly beneficial. “One is the retrofit side in order to be in compliance with regulation coming up to 2030 and thereby also not using more bunker than needed, but equally important is that findings are in cooperation on the newbuilding side when making specification and contracts going forward,” explains Jørgen Thuesen, Hafnia’s OS fleet, newbuildings and projects technical vice president.
Data generated is of particular interest, he explains: “We are already working on different topics from the findings in the report. One of the learnings from the project is that data is needed for the operation pattern and load profile for different equipment onboard of the vessel, not big data, but defined data.”
Thuesen notes that retrofitting’s role Hafnia’s decarbonisation strategy has not significantly changed as a result of the report, it instead acts as a support moving forwards to best meet upcoming industry targets.
Optimisation data calculated for each retrofit technology is accumulated into overall potential fuel and emission saving figures for each case study. Although the lowest fuel saving potential of 11.1% is recorded on DFDS’ Victoria Seaways, its CO2 reduction was the largest with an equivalent of 7,350tonnes per annum saved each year compared to Hafnia’s 5,208tonnes and Maersk’s 2,425tonnes.
This lower 11.1% figure is largely due to Victoria Seaways’ operating route between Kiel and Klaipeda, and therefore the vessel’s longer operational hours per year compared to the two MR tankers, comments Schur Riis.
The highest potential fuel saving while upholding the three-year ROI was 27.1% on the Hafnia Lise, but this figure is dependent on the inclusion of route optimisation. Without it, its fuel savings drops by almost a third to 17.5%.
Whether this 27.1% is possible in reality, Schur Riis cannot confirm, but hopes that the report’s findings could be utilised by ship operators and shipowners managing long-term charters to debate energy optimisation in future contracts, regardless of who owns, charters and operates the ship.
The report’s findings were analysed on their potential to deliver a full ROI within three years, which Schur Riis says is the timeframe that suppliers are often faced with when talking to shipowners.
However, significant additional potential savings are possible without the three-year ROI requirement, and he hopes that the report will encourage shipowners to look at cases individually rather than locking in on a specific ROI. Schur Riis adds: “A calculation today will look different tomorrow. We have especially seen this in connection to the 2020 global sulphur cap requirements and the large decrease in prices because of Covid-19.”
Breaking even on retrofitting investments on a vessel within three years may be uncertain due to volatile fuel prices, but Schur Riis insists that the long-term benefits of the retrofit project’s findings will weigh heavily in the future.
