Benestad High Voltage Power Wet Mate Connection System Phase II

Benestad Solutions AS is in the process of developing a complete 18/30 (36) kVsubsea power string that includes Wet Mate connectors, penetrators, and drymate connectors for underwater power distribution. These subsea connectors are key components in systems that link transformers, pumps, and compressors located on the seabed. Renewable energy sources such as wind, wave, and tidal energy require subsea connectors to link modules and transmit energy to shore. With the use of these connectors, parts of the power system can be installed underwater, enabling installations further offshore and in harsher environments. In the oil industry, there is a growing shift towards subsea solutions instead of traditional oil platforms. This means that pumps, compressors, and other electrical equipment are placed on the seabed. In this context, connecting power cables in wet environments is one of the main cost drivers, affecting both the profitability of new field developments and the modernization of existing installations. The Benestad Subsea connector stands out with lower production costs compared to existing solutions on the market. Its reduced size, both in weight and volume, helps lower costs for subsea modules, installation, and maintenance. Additionally, built-in functionality allows for troubleshooting from the surface, without the need for expensive subsea operations. An important application for these connectors is the energy supply to subsea modules for gas compression and liquid pumps. This will contribute to reduced CO2 emissions and lower energy consumption. The core idea behind the subsea connector is the unique contact design, which enables the connection of power cables and modules underwater without the need to bring the equipment to the surface. This design philosophy will form the basis for a standardized portfolio of subsea connectors that meet the needs of both today’s and future applications.

The learnings from this development have been implemented in the design of the 72.5 kV Power string, which is part of the Ocean Grid project. The market of subsea power distribution is shifting towards 72.5 kV voltage rating, and it is beneficial to have one product to cover both voltage classes. At the completion of the Ocean Grid Project the 72.5 kV Power String will fulfill all requirements for both 36 kV and 72.5 kV applications. 72.5 kV Power Strings are necessary to enable power distribution for floating offshore wind.

Benestad Solutions AS is moving towards expanding our product portfolio of advanced subsea products for electrical power distribution to include a complete Wet Mate Connector string containing wet mate connector and/penetrator for subsea pumps, offshore wind, wave energy, compressors, transformers etc. The objective of this project is to complete the development of a 36 kV/2000A Power System String which is system integration of wet mate connector towards a connection system, system integration of penetrator towards subsea modules and qualification of the string including penetrator. This application is a continuation of an ongoing Demo 2000 project. During phase I of the project all critical functions in the female and male wet mate connectors were identified and each of these have been tested separately to verify that each of the solutions for these functions work. For phase II (which is the target of this application) a complete Power string with male/female connectors and penetrator will be qualified. Wet Mate Connector together with a cable and penetrator makes an complete Power System string. During the qualification will the power system be showcased both internally and to external potential customers. This will be an important aspect in the commercialisation of the product. In addition it will allow us to continue the completion of the connection system for the connector to enable the fully integrated Benestad WMCS which will include all required products for a complete subsea high voltage wet mate connection system. The core idea and design of the high voltage Power system string is that it can be used in any situation where high voltage connections are required under water. The same design philosophy can be used for a whole range of subsea electrical connectors required by the market today and in the future. The wet mate connector is well suited for use in offshore and marine applications. During phase I of the project new potential markets have opened up for high power connectors. The market for renewable energy will fit the wet mate connector well. Connectors for a wide range of green energy sources will be needed to cover the future market of offshore renewable energy. The power system string will consist of a ROV installable wet mate connector and penetrator that manage the power up to 25 MW. The power system string consist of a penetrator, which is a sealing between seawater and the internals of a module, and a wet mate connector which allows submerged connection of two cables. The Benestad power string will be unique in the market due to its combination of high power and low weight. Furthermore it allows for standardization in different sizes and configurations, reduced manufacturing cost, reduced size requirements towards interfacing equipment, and consequently a significant reduction of CAPEX and OPEX for customers as well as increased flexibility in development of field solutions.