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Environmental Ship Index Discount

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In the port of Rotterdam, sustainable seagoing vessels are rewarded. Vessels that score high on the Environmental Ship Index (ESI) receive a discount on seaport dues. The ESI is an international benchmark for emissions from seagoing vessels.

Aerial photo with view of Erasmus Bridge

ESI-air shows how ships perform environmentally with respect to nitrogen oxides (NOx), sulphur oxides (SOx), and carbon dioxide (CO2). Vessels that perform better than the legal norm will be rewarded a 10% discount on the gross tonnage part of the port dues. Since 01-01-2015, the discount is doubled when vessels also have low NOx emissions. Low NOx emissions are achieved by using LNG as fuel or large catalysts. The discount for clean vessels is in line with the policy of the Port of Rotterdam Authority on sustainable port development. In addition, since January 2022, vessels are given a discount if they have recorded their noise production and reported it using ESI-noise.

Conditions for ESI-air seaport dues discount

  • The discount applies to all vessels that have an ESI score of 31 or more upon their actual time of arrival (ATA) in Rotterdam.
  • Seagoing vessels with an ESI score of 31.0 points or more qualify for a ten percent discount on the gross tonnage part (GT part) of the seaport dues.
  • The discount doubles if the ship also has an individual ESI-NOx score of 31 or higher.
  • The discount applies to each call in a quarter, with a maximum of 20 calls per ship per quarter.
  • If the ESI score is adjusted by the International Association of Ports and Harbors (IAPH) to below 31 points, the discount paid must be repaid within four weeks. This also applies if the ship is given the 'inactive' status.
  • Ask for the discount when declaring the seaport dues. The discount is calculated automatically.

Attention to noise

Under the name ESI-noise, the Port of Rotterdam Authority gives a financial discount to ships that provide insight into their noise production on the basis of an internationally accepted standard.

Seagoing vessels that have used ESI-noise to provide insight into their noise production will receive a discount in the port of Rotterdam. Vessels can be given a € 312.50 discount per call, up to a maximum of 4 port calls per year (€ 1,250). To qualify, each vessel must provide a noise report prepared under what is known as the ‘NEPTUNES Protocol’. This protocol includes guidelines for conducting noise measurements and for drawing up the report.

Phase 1

Until the end of 2023, the noise produced by vessels will not be subject to assessment. Providing the noise report is currently all that is required to be eligible for the discount.

Conditions - ESI-noise seaport dues discount

  • The discount will apply to all vessels for which a noise report is submitted to the Port of Rotterdam Authority, provided we have subsequently been able to verify the quality of the report. Verification will take place under the guidelines of the NEPTUNES Protocol. The report can be sent digitally.
  • The processing of reports and the verification of their quality takes place at the Port of Rotterdam Authority in accordance with the General Data Protection Regulation (GDPR). The data will be used exclusively for this purpose. See our privacy statement.
  • The discount will be paid out retrospectively (on an annual basis) to the office of the ship’s agents who submitted the statement for the vessels/voyages concerned.

For questions about the calculation of the ESI score, please contact the ESI Office of the International Association of Ports and Harbours.

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