Concept paper 4: The benefits

The modular Hub-and-Spoke concept, as a building block in a step-by-step and international coordinated roll-out, has multiple benefits over a national and incremental approach. First of all, cost savings can be made. The Hub-and-Spoke concept taps into infrastructure synergies by merging offshore wind farm transmission assets and interconnector assets. Independent wind farm connections are usually only utilised up to a capacity factor of approximately 50% due to the capacity factor of offshore wind farms. Interconnectors are can be utilised to a larger degree. By combining these asset types, the utilisation of individual connections could increase significantly to 65%.

In addition, a hub-based wind farm transmission concept can reduce costs compared to radial platform connections. This is due to benefits of scale by using e.g. island-based foundations and reduced operational expenses. The following figure gives an overview of the cost reduction potential for the Hub-and-Spoke concept as found in different assessments.

Benefits for society

The Hub-and-Spoke concept offers multiple benefits for society. Increased offshore wind deployment and interconnection levels between North Sea countries result in reduced electricity prices and emissions through improved system integration of renewables. A cost benefit analysis conducted by the consortium found that connecting 12-24 GW of offshore wind capacity in the North Sea – through an all-electric Hub-and-Spoke concept – would increase social welfare by approximately €1.0-1.7 billion per year for the whole of Europe by the year 2040, compared to radially connecting these offshore wind farms (without interconnections).

In addition, the increased interconnection levels reduce the amount of required dispatchable (fossil) power, resulting in a reduction of CO2 emissions of approximately 4% for the power sector the whole of Europe by 2040, for a 24 GW hub.