A recent study led by Benoit Sagot from ESTACA’Lab in France sheds light on the emissions profile of dual-fuel LNG-powered cruise ships, a topic that’s increasingly important as the maritime industry navigates stricter environmental regulations. Published in Atmospheric Environment: X, this research is particularly timely given the ongoing push for greener shipping solutions.
The study monitored emissions during sea trials of a new cruise ship equipped with a 4-stroke dual-fuel engine, which can run on both liquefied natural gas (LNG) and marine gas oil (MGO). The findings reveal that while LNG significantly reduces sulfur and nitrogen oxide emissions, there’s still work to be done regarding unburned methane, especially at lower engine loads. Sagot noted, “At 25% engine load, we observed an emission factor of 8.5 g.kWh−1 for unburned methane, a stark contrast to the stable 2.3 g.kWh−1 seen at higher loads.”
This is crucial for ship operators who are increasingly looking to LNG as a cleaner fuel alternative. The research highlights that switching from MGO to LNG can dramatically cut fine particulate emissions, with a reduction factor of about 136 at high loads. However, the real challenge lies in managing emissions at lower loads, where the engine tends to be less efficient and emits more methane.
From a commercial perspective, these insights present both challenges and opportunities. Operators can optimize their engine loads to minimize emissions, which not only helps in compliance with regulations but can also lead to cost savings in fuel consumption. The study indicates that less than 7% of the engine operating time was spent below 30% load, where emissions start to spike. This suggests that careful planning of operational profiles could be beneficial.
Moreover, the research points out that switching back to MGO at a 75% load results in an 18% increase in CO2 equivalent emissions. This kind of data is invaluable for maritime companies looking to balance operational efficiency with environmental responsibility. Sagot emphasizes the importance of these findings for the industry: “When considering a usage-weighted average, we obtained an emission factor of 3.2 g.kWh−1, which is lower than the FuelEU regulation threshold.”
As the maritime sector continues to evolve towards more sustainable practices, studies like this provide a roadmap for reducing greenhouse gas emissions while maintaining operational efficiency. With the insights garnered from these sea trials, ship operators can make informed decisions to enhance their environmental performance. This research not only contributes to the understanding of dual-fuel engines but also paves the way for a greener future in maritime transport.
For those in the industry, keeping an eye on such developments is essential, as they could very well shape the future of shipping regulations and operational practices. The findings from Sagot and his team not only highlight the potential of LNG as a cleaner fuel but also underscore the need for ongoing innovation and adaptation in the face of evolving environmental challenges.
