LPG as marine fuel with supportive technologies could deliver significant carbon reductions, report shows

Liquefied petroleum gas (LPG) as marine fuel, in combination with emissions reduction and energy-saving technologies such as onboard carbon capture and storage (OCCS), could deliver a significant carbon reduction and help shipowners comply with future stringent regulations, according to a new joint report from Lloyd’s Register (LR) and the World Liquid Gas Association (WLGA).

The report ‘Fuel for Thought: LPG’, which focuses on the cost, availability, and lifecycle assessment benefits of LPG as a marine fuel, shows the market for dual-fuel LPG engines will continue to grow based on a healthy orderbook, with LPG offering a cleaner, lower carbon emission marine energy source than many alternatives currently available.

The report found that using LPG as a marine fuel combined with technology such as OCCS can reduce a vessel’s emissions profile, with the added benefit of reducing the required CO2 storage capacity, due to the lower CO2 emissions from LPG combustion. This allows the technology to work more effectively and offers shipowners a pathway toward future regulatory compliance.

However, the uptake of LPG as a significant candidate either as a zero or near-zero emission fuel, or as a transitional fuel, comes with certain challenges and will depend on the pace and scale of decarbonization of the fuel production, and how quickly other supportive energy-saving technologies, such as carbon capture, can mature, the report indicates.

According to the report, the scale-up of decarbonization of fuel production is anticipated to increase as traditional LPG users seek to reduce their environmental impact. Demand and seaborne trade is also expected to grow in the coming years, causing growth in the global fleet of LPG carriers and opening up an opportunity for further uptake of LPG as a fuel in that particular fleet.

The report also points to LPG’s potential to be used as a fuel in other vessel types since its transportation, storage, and use have been established over several decades, while supply and supply infrastructure are widespread. Although long-term projections of fuel prices – especially when considering new renewable fuel types – LPG could also offer attractive operating and capital costs compared to other alternatives.

Panos Mitrou, Global Gas Segment Director, Lloyd’s Register, said: “The pace and scale of renewable production for LPG remains a critical factor in initiating the wider adoption of LPG as a marine fuel. Supportive energy-saving technologies, as along with potentially maturing onboard carbon capture and storage, will further assist in making LPG a viable low-zero carbon fuel. By ensuring this, LPG could offer attractive operating and capital costs compared to other alternative fuels as shipowners look to decarbonise their fleets in line with more stringent regulations.”

Additionally, technology readiness will need to improve and the range of available engine technologies will need to be expanded to enable widespread adoption of LPG on multiple vessel types. Currently, there is no four-stroke marine engine capable of using LPG, meaning auxiliary engines on vessels would need to be decarbonized through an additional fuel.

What is more, the report emphasizes that a safe bunkering framework must be also developed to encourage the uptake of LPG.

The regulatory framework for LPG use, particularly for bunkering, remains patchy, with the first interim guidelines for ship construction and design only just started at the International Maritime Organization (IMO) level, LR and WLGA state in the report.

Nikos Xydas, World Liquid Gas Association Technical Director, added: “LPG stands as a unique and exceptional energy source, pivotal for decarbonising the shipping sector. Stored and transported as a liquid and consumed as a gas, it is well recognised for its lower emission benefits as a marine fuel.

“With a surge in orders for LPG-fuelled ships, it’s clear that LPG’s role in the shipping industry is expanding. As the world moves towards deep decarbonisation targets, LPG emerges as an ideal fuel for all vessel types, offering a cleaner alternative fuel today and a pathway for an even cleaner future tomorrow. Its flexibility, low emissions, and cost-effectiveness position LPG as the potential fuel of choice in the shipping sector, paving also the way for low-cost deep-sea decarbonisation with the advent of bio/renewable LPG.”