Offshore electricity storage development project launched

Partners demonstrate benefits of offshore electricity storage and accelerate developments in offshore wind sector

Sixteen European offshore renewable energy companies have joined forces in project OESTER (Offshore Electricity Storage Technology Research). This three-year initiative, with TNO and energy sector companies such as RWE and Vattenfall, aims to accelerate the development and deployment of offshore electricity storage technology. Electricity storage can be a solution to grid congestion and energy system instability.

Grid congestion and system instability often lead to the limitation of electricity production. This reduces the effective use of renewable resources and limits their potential to accelerate the energy transition. In addition, simultaneous electricity production from multiple wind farms can lead to oversupply, causing electricity prices to fall sharply. This affects the business case of offshore wind farms. Energy storage systems can be a solution to these challenges.

Goal: scalable solutions

The mission of the OESTER project is to further develop and validate innovative offshore electricity storage solutions from technological, economic, environmental and societal perspectives. It will ultimately need to lead to scalable solutions that can be applied worldwide to accelerate the deployment of renewable energy systems. Among the technologies being evaluated during the project are the following:

• Short-term storage: batteries integrated into wind turbine towers (Verlume)
• Medium-Term Storage: Compressed Air Energy Storage (FLASC) and Underground Pumped Hydro Storage (Ocean Grazer) on wind farms
• Long-term storage: electrolysis system on an offshore platform directly connected to wind farms (Battolyser)

Basic designs and prototypes are being developed to validate these hybrid systems. Digital twins, virtual versions of the hybrid system to accurately represent physical operations, are being used to simulate system performance and optimize network integration on a gigawatt scale.

Next-generation wind farms

By integrating storage systems into offshore wind farms, the project supports the development of the next generation of offshore wind farms. Future offshore wind farms could become advanced, versatile energy hubs that combine wind, energy storage and possibly other renewable technologies. These integrated energy farms are designed to deliver energy continuously, improving system reliability and flexibility on the supply side.

The project falls under Mission-Driven Research, Development and Innovation (MOOI) of the Netherlands Enterprise Agency.

Partners

Partners involved are:

• wind developers and operators: RWE, Vattenfall, APG and SSE
• Storage technology developers: Verlume, Flasc, Battolyser systems and Ocean Grazer
• companies that support renewable energy and offshore storage: DMEC and SeaWay7
• Research and knowledge institutes supporting ecology and digital twins of the system: Deltares and University of Groningen and TNO (project coordinator)
• New ground law and the trade association of the Dutch energy storage industry, Energy Storage NL