April 29, 2015 – Siemens has launched a new alternating-current (AC) grid access solution for connecting near-shore wind power plants to the grid, replacing the conventional AC transformer platforms.

The new solution consists of an offshore transformer module (OTM) attached directly to a wind turbine, and acts as a distributed transmission asset, Siemens said. Nominally rated in incremental 250MW blocks, it can be linked together to provide the required transmission capacity even for very large wind parks, the company added. The device can be installed on a wind turbine foundation separately. As an alternative, it can be installed at the transition piece between foundation and turbine shaft like a balcony. According to Siemens, it is suitable for all wind power turbine models.

Siemens said its goal is to reduce the costs of wind power generated offshore to below 10 euro cts/kWh by 2020. Construction, transport, installation, operation and maintenance of the platform account for a high portion of the total grid access costs but these will be reduced by up to 40% with the new solution, said Siemens, as it is one third smaller in size and weight compared to a conventional AC platform.

The company also noted that no fans and diesel generators are necessary as a number of optional ancillary systems are removed. Additionally, the use of ester liquids instead of mineral oil makes this solution environmentally friendly, Siemens said.

PHOTO: The new alternating-current (AC) grid access solution from Siemens consists of an offshore transformer module (OTM) attached to a wind turbine, and acts as a distributed transmission asset. (Photo courtesy of Siemens.)