Greenhouse Gas (GHG) Rating Improvement

Green House Gas Ratings

Webinar: Improve Your GHG Rating, Enhance Your Edge

In this 30-minute webinar, Georgios Plevrakis, ABS Global Sustainability Director, and Lefteris Karaminas, ABS Global Sustainability Manager, will provide insight into the challenges facing owners in improving their GHG ratings, pathways for overcoming those challenges and how ABS can assist you along the way.

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Greenhouse gas (GHG) ratings have become an important factor for vessel charterers as they consider the available vessels and fleets. An increasing number of shipowners and operators are looking to voluntarily monitor, report and improve their GHG emissions.

Often a better GHG rating is indicative of a more fuel-efficient vessel, which makes it more attractive to potential charterers.

Additionally, the IMO’s Marine Environment Protection Committee (MEPC) adopted a new strategy to reduce greenhouse gas emissions from the shipping industry. The strategy seeks to reduce emissions by 50% (compared to 2008 emission levels) with the goal of eventually phasing them out. This target indicates that the global shipping industry is committed to reducing GHG emissions.

Shipowners and operators have begun exploring more fuel-efficient vessels and low-carbon fuel options.

GHG Rating Services for Vessel Owners and Operators

As shipowners and operators look to improve their environmental ratings to both maintain and attract potential charters, they face complex decisions on how best to identify, report and reduce GHG emissions.

ABS offers a variety of services and solutions to help improve GHG ratings. These services include benchmarking, verification of efficiency measures and calculations and vessel optimization. ABS provides its clients with proven technical knowledge and practical experience for GHG reporting and reduction.


Some of the major environmental rating organizations suggest having efficiency measures and calculations independently verified by classification organizations.  In fact, there are cases where the vessel’s current rating has improved just by ABS providing verification. 


Calculating GHG ratings requires an appropriate speed power curve.  Data to calculate an appropriate speed curve may be difficult to obtain.  For example, vessels built prior to 2013 had speed-power prediction for the design or ballast drafts, but not at the scantling draft.

Because this is such a key component of the GHG Rating calculation, ABS has developed tools that emphasize the estimation and calibration of the speed-power curve at the scantling draft corresponding to the sea trial condition.  This ensures that all pre-requisite information is prepared to allow for the estimation of the GHG Rating.


ABS can provide the necessary report, helping you demonstrate to your environmental rating organization that ship-specific information has been verified.  Gaining verification of applicable efficiency measures may improve your environmental ratings. Examples include verifying results after implementation of low friction coatings and/or propulsion improvement devices, with measurements taken during voyages.


Understanding how your vessel compares to others in its peer group, those of similar type and size, can help you determine if it is advantageous to improve your GHG rating. Through its benchmarking service, ABS compares your vessel with other vessels in the applicable peer group. Once you know how your vessel compares to others, you are better prepared to make decisions.


ABS offers a variety of services to assist owners in improving their GHG Ratings.  Improvement options through implementation of Energy Efficiency Technologies and/or Engine Power Limitation are among the methods used, enabling ship owners to choose the solution best suited for their vessel. 

ABS offers a broad spectrum of technical reviews, evaluations and life cycle cost analysis. ABS services are applicable to new construction and existing vessels and include: 

  • Energy Saving Device (ESD) Evaluation
  • Engine Power Limitation (EPL) Method
  • Minimum Propulsion Power assessment
  • Verification of efficiency gains from modifications
  • Bulb replacement guidance

To learn more about the energy efficiency services ABS offers, please contact ABS.