What do the terms conventional and unconventional mean? In everyday life, this question may be rather unimportant and always open to redefinition. In a technological context, however, it becomes highly significant. Here it is essential to use these terms carefully, especially when it comes to performance requirements or technological solutions. This is why the CIMAC WG 21 “propulsion” has taken on the issue.
The Working Group consists of azimuthing propulsion, engineering companies, research organisations, system component suppliers such as related electrical equipment & automation, controls, gears, thrusters and system integrators including engine users, shipyards, and classification societies. They assume that there is a consensus in the global shipping industry on the meaning of “conventional” and “unconventional”. However, these terms are not defined in documents of the International Maritime Organization (IMO) or international standards. And yet the performance requirements for certain technologies are based on these terms.
Hence, WG 21 believes that the terminology and usability of these terms should be carefully considered. In its position paper, the group has taken a closer look at the terminology “conventional” and “unconventional” used in regulatory frameworks, highlights industry concerns regarding the use of terminology, and proposes an approach to overcome the current challenges.
“There is no clear definition for `conventional´, `traditional´ and similar term, even they are used frequently in IMO documents and other industry papers, and popular wording can mislead and imply a wrong interpretation”, says Tero Tamminen, Steerprop Oy, Chairman of the WG 21. "That is why we propose for example, that the maturity of propulsion arrangements should not be based on whether they are conventional or unconventional.”
Download the full paper here.
The CIMAC Congress from May 19 to 23, 2025 in Zurich will be a perfect opportunity to discuss this topic and many others further. Visitors can expect over 200 presentations, poster sessions, panel discussions and an exhibition, as well as an extensive supporting program. More information on the CIMAC Congress is available here.