Sulphur Oxides (SOx) are emitted when marine or other liquid fuels containing Sulphur are combusted. Sulphur Oxides are air pollutants that contribute to acid deposition, which can lead to changes in soil and water quality. The subsequent impact of acid deposition can be significant. As a secondary particulate matter precursor, SOx also contributes to the formation of particulate aerosols in the atmosphere and therefore can ultimately lead to negative effects on human health.
The Sulphur Directive
In the EU, SOx emissions from ships are regulated by Directive (EU) 2016/802, known as the 'Sulphur Directive'. It establishes limits on the maximum Sulphur content of gas oils, heavy fuel oil in land-based applications as well as of marine fuels. The Directive also contains some additional fuel-specific requirements for ships calling at EU ports, obligations related to the use of fuels covered by the Directive and the placing on the market of certain rules.
The most important reasons for the successful implementation of the EU Sulphur Directive are:
- EU support mechanisms and technical assistance: The Commission has worked extensively with the EU Member States and the maritime community in the European Sustainable Shipping Forum (ESSF). The European Maritime Safety Agency provided sound technical assistance to Member States.
- Combination of voluntary and mandatory tools: A new and voluntary electronic enforcement system. By the end of March 2018, around 30,000 sulphur inspection results had been registered.
- EU financial support for the uptake of clean ship technologies: The Commission actively supports cleaner maritime transport through a number of financial instruments aimed at research, development and deployment projects of innovative technologies of clean fuels.
- Synergies with the International Maritime Organization: the EU Smart and Technology-based Sulphur Compliance and Enforcement Strategy was recognized as a global Best Practice by the International Maritime Organization and is steering developments at global level to further reduce impact from shipping emissions.
Liquefied Natural Gas (LNG)
LNG as a Cleaner Alternative Fuel for Shipping
LNG does not contain sulphur, which results in (almost) no SOx emissions and almost no PM-emissions. In addition, because LNG has a higher hydrogen-to-carbon ratio in comparison to conventional fuels, the specific CO2 emissions are lower. It is possible to obtain different potential gains, both in terms of GHG and the emission of other relevant substances, depending on which source of information you use. It is therefore important to identify and understand the conditions and assumptions contributing to the abovementioned environmental benefits.
The Report from the Commission to the European Parliament and the Council, on implementation and compliance with the Sulphur Standards for Marine Fuels set out in Directive (EU) 2016/802, relating to a reduction in the sulphur content of certain liquid fuels, refers to the use of Liquefied Natural Gas (LNG). The use of LNG as an alternative fuel has the potential not only to reduce SOx emissions, but also to significantly reduce Nitrogen Oxide (NOx) emissions as well as particulate matter when compared to heavy fuel oil. Worldwide, there are currently over 200 ships (already operating or on order) using LNG as an alternative fuel, covering a wide range of ship sizes and types. Nevertheless, potential methane (CH4) emissions resulting from the use of natural gas in ship engines need to be controlled to ensure the overall environmental benefits of using LNG as shipping fuel.
The ESSF sub-group on 'LNG as Marine Fuel' works on developing uniform rules that would ensure the safe and sustainable use of LNG in the EU, but also internationally. In February 2018, EMSA published a Guidance document on safe bunkering of LNG for port authorities and administrations which is largely based on the work and experience of the experts in the ESSF. Directive 2014/94/EU on the deployment of alternative fuels infrastructure foresees further standardization of LNG refueling points for sea-going ships and inland waterway vessels in European ports to facilitate their operation across the EU. Various Member States also announced further measures to promote alternative fuels for maritime transport in their 'National Policy Framework' adopted under Directive 2014/94/EU.
The impact of using LNG as fuel for transport can be regarded from two different perspectives:
- The net benefits of LNG as a replacement of oil fuels, in terms of local air pollution and
- The higher GHG emission potential of Methane (higher constituent of LNG). On one hand these promising environmental benefits have already granted to LNG a front-runner position as an alternative, fuel 23, but, on the other hand, the concerns with regards to the actual GHG life-cycle benefits of Natural Gas, as LNG as fuel, are still today in discussion, deserving significant attention and underlining the need to develop adequate mitigating measures. The challenge is to promote the benefits of using LNG as a fuel, whilst simultaneously reducing the potential negative environmental effects from its use.
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