In engines as well as cargo tanks, LNG is powering ahead
Aug. 11 2019
Less polluting than oil or coal, natural gas is the only fossil fuel for which, according to most future energy scenarios, production is expected to increase substantially. The result is an increasing number of LNG carriers at sea. And since maritime transport must comply with increasingly stringent environmental standards, the precious methane in its liquefied form can be also be used to power merchant shipping. This success has been enabled by a very strong culture of safety behind the scenes.
Natural gas is a fuel of the future available today. The increase in demand is expected to be 2% annually by 2030. Chinese imports play a major role in this development: natural gas is expected to account for 11% of primary energy in China by 2030, compared to 5% in 2015. But the Asian giant’s appetite for energy is not the only factor driving the success of the gas: its environmental performance also contributes significantly. Compared to fuel oil, its combustion, in fact, emits around 20 to 25% less CO2. It is also much cleaner than coal: when burned in power plants, it emits negligible quantities of sulfur dioxide and particulate matters, and reduces nitrogen oxide emissions by more than 80%.
The most talked-about fossil fuel
In an effort to diversify their supplies, importing countries are increasingly turning to the liquid form of the cleanest fossil fuel – liquefied natural gas. Transported at very low temperature (-160°C) by carriers that are frequently more than 125,000 cubic meters in volume, natural gas is thus accessible to importing countries that cannot or do not wish to use gas pipeline distribution. This particularly flexible distribution method is expected to increase by 4% to 5% a year on average over the period 2015-2030. China alone could assume 16% of global LNG demand by 2030. “It’s simple – LNG has established itself as the most talked-about fossil fuel!” said Carlos Guerrero, Global Market Leader, Tankers & Gas Carriers, Bureau Veritas.
The seaborne transportation of LNG has been recognized and managed since the 1960s, with the construction of the first liquefaction units and carriers exporting Algerian gas to England and France. From the very beginning, operators, manufacturers, ship owners and builders in this industry with its bright future ahead of it have benefited from the support of Bureau Veritas to ensure the safety and sustainability of the tankers themselves, as well as that of their equipment and easements onshore.
A highly rigorous industry
With the growth in demand, development of production and transport capacities has accelerated, with the United States establishing itself in just a few years as one of the leading production countries, thanks to shale gas fracking. “Many companies are suggesting such things as improved thermal insulation solutions to limit boil off-gas as much as possible,” explains Carlos Guerrero. “We also, of course, have to continue to certify the structure of the LNG carriers: the very large vessels – nearly 300 meters long – which most often leave Korean, Chinese or Japanese shipyards, are subject to very significant thermal, structural and safety constraints. We therefore also support the industry with risk analysis and other engineering consultancy services especially since new propulsion systems using LNG as a fuel are gradually installed on the ships, and they must also be certified.”
Using LNG as a fuel has also become an issue that extends to maritime transport in general, beyond just LNG carriers. This is because January 2020 will see the entry into force of the new International Maritime Organization (IMO) regulation requiring ships on all shipping routes to use fuels with a sulfur content that does not exceed 0.5%. It strengthens a provision that, since 2015, imposed a limit that was even more severe but was confined only to “emission control areas” defined by the IMO.
The problem is that a very large majority of ships use “heavy” fuels that do not comply with this limit. What are the solutions? New fuels being developed: ultra-low sulfur fuel oil (with a maximum sulfur content of 0.1%, and very low sulfur fuel oil, with a sulfur content of 0.1% to 0.5%). Cleaning systems such as “scrubbers”, which eliminate the exhaust gas of the undesirable sulfur oxides. And… that indispensable fuel, LNG, which some ships already use, either alone or in addition to other fuels.
LNG, better fuel for maritime transport?
A sign of the times: LNG is of interest to some heavyweights in the maritime tourism sector who rely on propulsion systems that are capable of burning both natural gas and conventional fuels, in order to mitigate the environmental impact of their liners.
What choices will shippers make to comply with the new IMO regulation? “There is no obvious answer since there are a great many factors, particularly economic ones, in a decision about fuel price trends,” says Carlos Guerrero. It does seem, though, that LNG is a good option whenever you want to choose a clean fuel. Bearing in mind that it is still a fossil fuel. By 2040-2050, we must therefore also think in terms of batteries, hydrogen, speed adaptation, and so on. But in the meantime, LNG is, at the very least, an excellent transition fuel and the technology is available today”.