Connection and Integration of Offshore Renewable Energy Farms into UK Power Systems - State of the Art Offshore Network Technology Report

Abstract:

The ETI has engaged Sinclair Knight Merz (SKM) to identify the opportunity for the development of innovative solutions for the collection of electrical energy from individual and multiple offshore renewable energy farms, and the transportation of bulk electrical energy from these offshore farms to the onshore power system. The study comprises four main tasks :

1. Offshore renewable scenarios – to define the timeline of the expected volumes of offshore renewable generation capacities
2. State of the art of offshore network technologies – establishment of the current state of the art of offshore network technologies and their prospective future development path
3. Analysis at individual farm level – identification of the challenges and resultant technology opportunities from connection of individual large-scale offshore wind or marine energy farms to the UKgrid system, and recommendations for connection solutions for investigation.
4. Analysis at multiple farm level – evaluation of the optimal architecture(s) that could be developed to collect, manage and transmit back to shore the electrical energy produced by multiple, large-scale offshore renewable energy farms.

• There were two main primary areas of focus for offshore network technologies:.
  1. Submarine cable systems - critical to the development of networks because they contribute such a significant element in terms of project cost, risk and technology developments and also impact on the optimisation of system architectures.
  2. HVDC systems utilising technology which currently exists are able to be applied to support the development of offshore renewables for projects which are growing in size,complexity and connection distance
• Interoperability and control issues and barriers to integration of technologies from different suppliers were not seen as significant.
• Major bottlenecks in the supply chain over the next 30 years - excluding those linked to wind turbines, the major constraint identified was that of subsea cables, where there is no UK subsea cable manufacturing capability.
• Technology Opportunities where ETI could focus future research: -
  • HVDC voltage standardisation ?
  • HVDC circuit breakers ?
  • HVDC multi-terminal control standardisation ?
  • HVAC collector voltage optimisation studies ?
  • Offshore cable reliability and repair improvements ?
  • Pilot projects to connect small generation sized units using direct DC connections ?
  • Alternative technologies for production of higher voltage power electronic devices
  • ?Alternatives to replace HVAC export cables
  • ?Offshore platform design including standardisation on approach for fire protection.
  • ?Marinisation of offshore connection equipment

Publication Year:

2010

Publisher:

ETI

DOI:

https://doi.org/10.5286/UKERC.EDC.000711

Author(s):

Sinclair Knight Merz