MHK Cost Breakdown Structure Draft

The generalized Cost Breakdown Structure (CBS) for marine and hydrokinetic (MHK) projects is a hierarchical structure designed to facilitate the collection and organization of lifecycle costs of any type of MHK project, including wave energy converters and current energy convertners. At a high level, the categories in the CBS will be applicable to all projects; at a detailed level, however, the CBS includes many cost categories that will pertain to one project but not others. It is expected that many of the detailed levels of the CBS will be populated with "NA" or left blank.

This version of the CBS is a working draft. The Department of Energy and the National Renewable Energy Laboratory welcome your comments and feedback. You may leave comments, here, in this forum, or you may submit comments in private via email to Scott Jenne at NREL (




MHK Cost Breakdown Structure

Thank you for visiting this forum to download the MHK Cost Breakdown Structure. We welcome your feedback.



It seems that some categories are mis-placed in the presented CBS. Here some specific items at level 3 that appear to be inconsistent with the structure:

CapEX -> BOS -> 

Mooring/Foundation should be part of the MEC Device Cost

Ancillary Marine Systems, this is presumably items like safety equipment. I would think that should be part of MEC Device

Subsea Cable System. Is this the riser cable? If so, it should probably be part of device cost. If it is the export cable, it should probably renamed to make it clearer. 

Assembly & Installation. Why is this not part of the MEC Device Cost? Transportation is included there, so it would be logical to place it there as well.  

Operation & Maintenance -> Operations

Consumables & Replacement Parts should probably be part of Maintenance

In general the breakdown is difficult to read because some of the most important items are hidden at level 3 or level 4. Examples are:

Consumables and Replacement Parts, this is a pretty dominant category and should be visible at level 2 not 3

Operating Insurance. It is not clear what kind of insurance this is. Typically these devices are insured for damage/loss etc. Is this insurance the operator needs to have to operate at sea? If so, where is the damage/loss insurance category, which typically makes up about 2% of CAPEX in the offshore industry? 




Thank you for your feedback

Thank you for your feedback, Mprevisic.

We are working on revising the CBS based on your and others comments and will have a revised CBS soon. Additionally, we will be holding a webinar to go through the CBS and LCOE guidance in more detail within the next few weeks.