Use Of EPL/SHaPoLi Power Reserve

To meet EEXI requirements, many ships have applied EPL or SHaPoLi as an overridable power limitation. In this case, the available power may be insufficient and overriding the power limitation may be necessary, which requires reporting and follow-up. This statutory news aims to inform on the release and use of power reserve.

Relevant for shipowners, managers and flag states. 

These are some important aspects on the use of power reserve when Engine Power Limitation (EPL) or Shaft Power Limitation (SHaPoLi) is applied to reduce power:

OMM – Onboard Management Manual for EPL/SHaPoLi

Ships which have opted for an EPL or SHaPoLi solution to comply with EEXI will, in addition to the EEXI Technical File covering the EEXI calculation, also have an approved OMM. This includes a technical description of the EPL/SHaPoLi installation, the process for release of power reserve and for reactivation of power limitation, recording and reporting requirements, etc.

Use of power reserve (releasing, reactivating, recording and reporting)

Use of power reserve by unlimiting the engine or shaft power limitation is only allowed if the purpose is to secure the safety of the ship or to save life at sea, consistent with Regulation 3.1 of MARPOL Annex VI, subject to the judgment of the Master or the Officer in charge.

Once the power reserve has been used, this shall be recorded in the record page of the OMM, including position/time when used, reason for using the power reserve and position/time of reactivation of power limitation (see Appendix for the complete list).

Information on the use of the power reserve shall then be reported without delay to the flag administration/RO (Recognized Organization) and the port of destination. The flag administration will report all cases of use of power reserve to the IMO on an annual basis.

In case the engine/shaft power limitation override is activated but the power reserve is not subsequently used, it is sufficient to record the event in the bridge and engine room logbooks without reporting the event to the flag administration/RO. The engine room logbook should then record the power used during the period when the override was activated, together with details on the reactivation of power limitation.

Finally, immediately after the risk has been mitigated, power limitation shall be reactivated and the ship operated within the limited power again as per the OMM. The reactivation shall then be confirmed with supporting evidence by the flag administration/RO based on the OMM procedure.

The following table summarizes the cases explained above, on logging, reporting and reactivation:

Use of EPL/SHaPoli - table

DNV (RO) – reporting and reactivation

As an RO responsible for issuing the International Energy Efficiency Certificate, DNV has enabled reporting and/or reactivation through a new occasional survey. In case power reserve has been used and/or reactivated, please create a survey request for a “Shaft/Engine power limitation reactivation survey” (remote) listed under “Occasional surveys / audits” on My Services on Veracity. The report and supporting evidence of reactivation can then be uploaded in the survey request and the reactivation will be confirmed and documented as per the OMM.


Without delay, operators are advised to report use of power reserve in cases of emergency. Failing to do so might result in findings during port state controls. Furthermore, operators are reminded to log all events on releasing power reserve as required, even when the power reserve was not used.


MEPC.335: 2021 Guidelines on the shaft / engine power limitation system to comply with the EEXI requirements and use of a power reserve


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