LPG Propulsion Explained

The Science

Pioneering the technology needed for LPG dual-fuel propulsion

From the very first day humans gazed upon the open sea, we’ve been looking for a better way to cross it. Today, it’s not just about doing it faster and more efficiently; it’s also about doing it more responsibly. BW LPG is proud to be the global pioneer in offering customers the world’s first fleet of very large gas carriers powered by cleaner-burning, cost-efficient LPG.

Pioneering the technology needed for LPG dual-fuel propulsion

As the world’s largest owner and operator of Very Large Gas Carriers, we looked at the heart of our business and our vessels. What if we could deliver cleaner energy to world markets, through cleaner means of propulsion? What if we could power our vessels with LPG? How can we do so when marine engines that can be powered by LPG does not exist?

By building on available technology. By investing in R&D, contributing resources and technical expertise in partnership with the world’s leading engine manufacturers. Together, we pioneered the world’s first dual-fuel LPG propulsion engine, which can seamlessly switch between LPG and conventional fuels.

How it works

First, LPG deck tanks are filled together with the LPG cargo tanks using the cargo system during loading. LPG is then drawn from the deck tanks into a fuel gas supply system and piped to the engine.

A small amount of compliant pilot fuel, such as diesel, is injected into the engine as the piston nears the top. It sparks under pressure, and LPG burns to create propulsive force.

Benefits of LPG propulsion

These world’s first LPG dual-fuel engines will reduce emissions of Sulfur Oxides (~97%), Particulate Matters (~90%), Carbon Dioxide (~15%) and Nitrous Oxides (~20%). This means that vessels powered by LPG will be in full compliance with current and future SOx emission requirements, including for Emission Control Areas (ECAs) and Sulfur Emission Control Areas (SECAs).

LPG propulsion also offer efficiency gains on many fronts. Output efficiencies will improve by ~11 percent with LPG when compared with compliant fuels. This means that we capture significant improvements in total voyage fuel economics. Other efficiencies include easy storage, faster refueling and wide availability of bunkering ships and facilities. Bunkering can be done directly at load terminal or via ship-to-ship transfer from smaller LPG carrier. With LPG, we eliminate bunker quality issues and spill risks.

And with dual-fuel capability, these engines provide fuel flexibility which translates to full redundancy to ensure uninterrupted operations, and buffering from fuel price sensitivities.

A stepping stone to more

Where does this technology take us? From here, to a zero-carbon future.

BW LPG is taking the lead and advancing technology towards zero-carbon fuel propulsion. We will continue to evolve to meet the needs of global trade, and offer safer, more efficient and environmentally friendly vessels, to deliver cleaner energy to world markets.

Powered by LPG, these vessels will propel us towards a Better World.