Reducing emissions; the need to act today
With uncertainty surrounding which technology will emerge to meet future emission reduction targets, much of the newbuilding orderbook remains with traditional fuels or LNG.
However, we need to reduce emissions today, and with ship performance no longer based on tonnes of fuels used, shipowners need solutions that will reduce volumes of emissions and capture CO2 before it enters the atmosphere.
Theoretically, biofuels and methanol are fuelling options for the future, but the availability and distribution network for the supply of these fuels are still nascent. LNG, on the other hand, has great appeal because the market, availability, distribution network and engine technology are already well established. If LNG is used to produce hydrogen on board, this pathway provides a proven, reliable and economically sustainable solution that will meet International Maritime Organization targets today and into the future.
An innovative but established, proven dual-fuel LNG/hydrogen engine configuration means vessels can use increasing amounts of hydrogen to maintain a top CII rating throughout their lifetime and meet the demands of IMO 2050 with the technology and fuel available today.
Hydrogen is produced by combining LNG with steam in a gas reformer on board the ship that splits LNG molecules into hydrogen and CO2, which is captured by splitting the LNG molecules rather than from exhaust gas. Hydrogen can then be directly used to fuel the internal combustion engines and power fuel cells.
Using LNG to produce hydrogen on board removes the need for new energy infrastructure to gain the benefits on offer. It also opens a new and exciting potential technological future by combining the concept with the use of modern ship propulsion arrangements featuring four-stroke, dual-fuel engines, which are also able to run on a fuel mix of LNG and hydrogen, leading to a notable reduction of greenhouse gas emissions at current market speeds and significantly lower capex and opex.
Eventually, for very large ships, the combination of the concept with gas turbines could represent a promising option because the increased efficiency provided by gas turbines means ships could benefit from increased energy for the same quantity of gas.
While actively working on ground-breaking propulsion arrangements, Rina established a connection with Cambridge University’s Energy, Fluids and Turbomachinery Division at the Department of Engineering. Through this relationship, Professor Epaminondas Mastorakos, a leading expert in gas turbine technology, has scientifically validated the dual-fuel LNG/hydrogen gas turbine propulsion system concept, and research papers on the subject have been published.
Rina technical director Antonios Trakakis commented: “The production of hydrogen using gas reformer technology has been a game changer for the shipping industry. It offers a solution that is based on readily available technology and fuels today that will meet increasingly stringent emission reduction targets throughout the lifetime of a vessel.
“This proven solution means shipowners can invest in top-rated CII newbuildings today with confidence and without risk. Research supports the novel application of an engine technology that ensures fuel flexibility and adaptiveness to a constantly changing world. This is even more exciting and offers the wonderful potential of another technically viable, practical solution to enable the industry to act today for the sake of tomorrow.”