ClassNK approves SRC’s retrofit methanol storage solution

October 1, 2025, by Aida Čučuk

Japanese classification society ClassNK has granted approval in principle (AiP) to UK-based marine and offshore solutions provider SRC Group for its Methanol Superstorage solution, a tank design concept incorporating Sandwich Plate System (SPS) technology to increase shipboard storage capacity for both methanol and ethanol.

It is understood that the AiP confirms that the Methanol Superstorage is feasible for the intended application in accordance with ClassNK’s ‘Guidelines for Ships Using Alternative Fuels, Part A: Guidelines for Ships Using Methyl/Ethyl Alcohol as Fuels (Edition 3.0.0).’

As explained, the solution features SPS technology – a solid elastomer core “sandwiched” between two steel plates that is 25-millimeter-thick. It reportedly delivers 85% more storage capacity than a conventional tank.

Ryohei Sakai, Manager (Project Hull), Technical Solution Department, ClassNK, stated: “With many methanol-ready ships now in operation, under construction or on order and ethanol also gaining traction, fuel storage has become an area of intense industry interest. Because of its low volumetric energy density compared to HFO, a methanol tank would need to hold over twice the volume to generate the same energy, for example. This has consequences for ship range and design. SRC’s methanol fuel tank concept represents an approach to addressing this challenge.”

The Panama Maritime Authority also granted AiP for the retrofit methanol storage solution, as methanol-fueled vessels follow an alternative design process in which the final approval rests with the flag state.

Alex Vainokivi, Innovation Manager, SRC Group, commented: “Receiving Approval in Principle for Methanol Superstorage from both ClassNK and Panama Maritime Authority represents a major step forward for SRC in our mission to achieve widespread industry acceptance for the solution. A Methanol Superstorage tank delivers almost twice the fuel storage volume of a traditional tank, while the SPS provides a triple barrier for fire protection, leak prevention and higher impact protection. It can also be retrofitted with minimal impact on the vessel’s general arrangement.”

To note, the Methanol Superstorage solution was previously approved by Italy-based classification society RINA and UK-based classification society Lloyd’s Register (LR).