The Rise of LPG in the Maritime Industry. How does it power ships?
Liquefied Petroleum Gas (LPG) is emerging as a promising alternative fuel for the maritime industry, offering a cleaner, more sustainable option for powering ships. As the shipping sector seeks ways to reduce its environmental footprint, LPG stands out due to its lower greenhouse gas emissions and near elimination of sulphur emissions compared to conventional maritime fuels.
Benefits of LPG as an alternative fuel in the maritime industry
The International Maritime Organization’s (IMO) stringent regulations on sulphur content have propelled the adoption of LPG as a ship fuel. LPG’s ability to comply with both local and global sulphur restrictions, coupled with its reduction in nitrogen oxide (NOx) emissions, positions it as an attractive solution for the industry. Moreover, LPG’s existing global infrastructure, including storage and loading facilities, supports its viability as a marine fuel.
The Future of LPG as a marine fuel: Ensuring safety and compliance
The transition to LPG is further facilitated by the development of new class rules and safety codes, such as the IGF Code, which ensure the safe and efficient use of LPG in shipping. With advancements in engine technology and a growing commitment to decarbonisation, LPG is poised to play a significant role in the future of maritime fuel, steering the industry towards a more sustainable horizon.
The road to decarbonising maritime transportation is long, and LPG offers a promising path with the potential to significantly reduce the industry's environmental footprint. Continued development and collaboration are crucial to overcome existing challenges and unlock the full potential of LPG as a fuel for shipping.
Latest content, downloads and tools
Back to: Fuel for thought hub
Liquefied Petroleum Gas (LPG) FAQs
LPG stands for Liquefied Petroleum Gas. It is a mixture of hydrocarbon gases, primarily propane and butane, that can be liquefied through moderate pressure or cooling. LPG is widely used across domestic, industrial and transport sectors, including as a marine fuel and cargo.
LPG marine engines typically operate as dual-fuel. LPG is stored onboard as a liquid, converted into gas before combustion, and used to power the vessel. Ships may switch between LPG and conventional marine fuels to suit operational requirements.
LPG is stored in specialised cargo or fuel tanks designed to safely contain the fuel under pressure, refrigeration, or a combination of both. Storage arrangements vary by vessel type and intended use, with systems designed to maintain fuel/cargo integrity while minimising evaporation and ensuring safe operations.
LPG carriers are generally classified as fully pressurised, semi-refrigerated, or fully refrigerated vessels. They also vary in size, from small coastal gas carriers to Medium Gas Carriers (MGCs) and Very Large Gas Carriers (VLGCs) serving international trade routes. The vessel type selected depends on cargo volume, trade patterns and storage requirements.
LPG shipping supports a range of industries including energy, petrochemicals, manufacturing, agriculture and residential heating. Maritime transport enables the movement of LPG from producing regions to global markets where it is used as fuel, feedstock or for industrial processes.
In maritime applications, LPG refers to liquefied petroleum gas transported as cargo or used as a marine fuel. It has an established global supply chain and is already widely carried by dedicated gas carriers. Interest in LPG as a fuel has grown as shipowners assess different pathways for reducing emissions and meeting regulatory requirements.
LPG and LNG ships are both designed to transport liquefied gases, but they carry different cargoes under different storage conditions. LPG carriers generally transport propane and butane (among other possible liquefied gases) using pressure, refrigeration or both, while LNG carriers transport liquefied methane at much lower temperatures at cryogenic conditions near minus 160 degC. These differences influence vessel design, containment systems and onboard equipment.
LPG carriers incorporate specialised containment systems, gas detection equipment, emergency shutdown systems, ventilation arrangements and fire protection measures. Crew training, operational procedures and compliance with international safety standards also play a key role in managing the risks associated with handling liquefied gases.
LPG can reduce certain air pollutant emissions compared with some conventional marine fuels, including sulphur oxides (SOx), particulate matter (PM) and nitrogen oxides (NOx). However, overall life cycle environmental performance depends on factors such as fuel production pathways, vessel efficiency and lifecycle greenhouse gas emissions. As with all marine fuels, its benefits and challenges should be evaluated across the full value chain.[
An LPG carrier is a specialised ship designed to transport liquefied gases in bulk at temperatures not below minus 55 degC. These vessels use dedicated containment systems to maintain LPG in liquid form during transport and may carry propane, butane, ammonia or other liquefied gases depending on their design and certification.
LPG ships are governed by international regulations covering ship design, construction and operation. Key frameworks include the International Code for the Construction and Equipment of Ships Carrying Liquefied Gases in Bulk (IGC Code) and, where LPG is intended to be used as fuel on board non-gas carriers, the Interim Guidelines for the safety of ships using LPG fuels published by IMO under MSC.1/Circ 1666 on 30 June 2023.
