A new project to build industry consensus on setting the future standard array voltage for offshore wind farms has been launched. The High Voltage Array Systems (Hi-VAS) project is the latest joint industry initiative led by the Carbon Trust as part of the Offshore Wind Accelerator (OWA) programme. It aims to understand the costs, benefits and technology challenges associated with raising the array voltage.
The wider consortium of the Hi-VAS project consists of seven wind farm developers: EnBW, Equinor, Ørsted, RWE, ScottishPower Renewables, Shell and Vattenfall. The half-million pound project is set to run until January 2022 and is being delivered by the Carbon Trust, TNEI and Petrofac.
As offshore wind turbines are set to grow beyond 15MW, it is widely agreed within the industry that the current standard array voltage of 66kV will be insufficient. A higher array voltage will be necessary to enable cost-effective string lengths and layout designs; reduce electrical losses; and ultimately enable the deployment of larger turbines. However, uncertainty remains as to what the optimum next array voltage is; the appropriate timing for making the change to the next array voltage; and the most efficient path to the next array voltage in terms of technology and regulatory development.
The technical and regulatory changes required when raising the array voltage will be examined. Detailed cost-benefit analysis, risk analysis and preliminary design studies will be performed for a range of possible future array voltages and a range of future turbine sizes (14-20MW) to identify the next optimum array voltage.
