Marine renewables have made great strides in recent years. The IEC, ABS, and DNV GL continue to generate standards and recommended practices in an effort to formulate approved processes as the renewable products make their way offshore and into the market. There are many similarities in some of the processes and designs when compared to oil and gas structures, especially when it comes to moorings. However, many design areas are uniquely related to renewables, even within the same field of energy conversion (e.g. multiple types of wave energy converters). As more renewable systems are installed, the standards will continue to transition from philosophical to more prescriptive recommendations. One area in which the lines are blurred between oil and gas and renewable industries is mooring systems. The interdependency between the mooring and power generation systems plays a crucial role early in the design phase. Modeling marine energy converters and the mooring system can be complex due the variability of moving parts, and without proper attention, it may be easy to underestimate the loads and fatigue cycles to which moorings will be exposed. Moorings for these structures should incorporate existing standards and recommended practices to ensure safety and reliability. Inspection, maintenance, repair, and replacement should also be considered. As the renewable industry continues to move forward from scaled prototypes to farms of devices, the oil and gas supply chain will contemplate when to become involved from a financial and resource perspective. However, there are still hurdles within the US authorization bodies like BSEE, BOEM, FERC, NOAA, USCG, etc. to overcome. This paper addresses the existing mooring related standards and delineates areas that need further refinement or conservatism as the renewable industry moves forward with the installation of offshore energy converters.

Although preventive maintenance is not a new concept when dealing with mooring systems, experience shows that the implementation is not always successful. As important as new technologies are in improving mooring integrity, it is equally important to ensure that well-established best practices remain in place. As the industry approaches a period where extending service life of floating structures is desirable, but the existing mooring system has reached the twilight of its service life, the need for properly maintaining the mooring system is more acute. With time on their side, the prudent operator can implement small regular steps to extend mooring system service life. This paper presents methodologies to maximize design life by highlighting design and operational best practices, maintenance and monitoring, and identifying common reasons why these best practices are not implemented.