Use of LNG as Fuel for Shipping and Inland Waterways Transport

Transport is undergoing an energy transformation to meet the objectives of policies to improve air quality and combat global warming.

Liquefied natural gas (LNG) appears to be one of the fuels that can reduce both emissions of atmospheric pollutants (sulfur oxides, nitrogen oxides, fine particles) and greenhouse gases (GHGs). It is presented as the fuel that can help meet the objectives of climate change and air quality policies.

The choice of propulsion fuel is the key element in adapting sea and river transport to stricter regulations on air quality and the reduction of GHG emissions, alongside other technical measures (optimization of hull shapes and auxiliaries, choice of navigation routes, ship speed, use of batteries or fuel cells, vellic propulsion, digitization of the logistics chain to reduce waiting times and energy consumption).

To comply with international and European regulations, shipowners use heavy fuel oil, but are obliged to fit ships with smoke scrubbers, or low-sulfur heavy fuel oil, or marine diesel, or light marine diesel, or methanol.

LNG is the alternative fuel for maritime and inland waterway transport selected by Directive 2014/94/EU of October 22, 2014 on the deployment of an infrastructure for alternative fuels. However, the use of LNG remains subject to economic, environmental and technical constraints. In their choice of propulsion fuel, shipowners take into account the costs of adapting their fleets, whether by modifying vessels in service or by building new ones, and the costs of operating vessels over their lifespan, averaging 20 to 30 years. The economic aspects require special study, and will not be discussed in this article.

Around 200 ships in service or under construction are LNG-powered, out of a total of just over 90,000 ships in service, and projects are growing to represent 13.5% of orders in gross tonnage for 2018 and beyond. In fact, the key issue is whether LNG meets the objectives set by current environmental and climate regulations, or those likely to be enacted in the coming years. The article therefore sets out to present the energy transformation of sea and river transport, driven by policies to improve air quality and reduce greenhouse gases, and to examine whether the use of LNG meets these policies (§ 1