In 10 years, the Offshore Wind Accelerator (OWA) has run over 150 projects supporting innovations that have led to both a significant reduction in the cost of energy and risk, whilst making offshore operations safer. To mark this milestone in R&D collaboration, we have selected 10 high impact innovations to showcase the breadth and depth of the programme.
One of the reasons windfarms are expensive to build is because of the cost of bringing the electricity they generate back to the mainland efficiently. In fact, the transmission infrastructure, cabling and substations, typically accounts for 10-20 per cent of the capital cost of an offshore wind farm.
A large part of that cost is related to the development, manufacture and installation of offshore substations – which convert voltage to 155kV or 220kV, which is then transported to shore.
But how can the cost of substations be reduced? Can they be made smaller? Lighter? The OWA explored these opportunities.
We looked at a 1GW HVDC connected wind farm and examined the possible opportunities for cost reduction in transmission assets by combining two HVAC substations and the HVDC converter platform on a single jacket substructure.
The key findings of this study is that a combined HVAC+HVDC topside could be delivered weighing less than 10,000 tonnes using currently proven HVDC technology.
This presents a real opportunity for a reduction in both upfront and operating costs.
We also investigated the possibility of reducing an offshore substation down to its bare essentials so that we could place the components on smaller substructures, removing the need for large heavy lift vessels.
In 2015, we launched a study to investigate the benefits of this concept even further, and to get it ready for deployment at the Beatrice offshore wind farm in Scotland. By investigating the engineering and regulatory challenges, we provided a better understanding of this solution.
This article is part of 10 years, 10 innovations: A summary of the impact of the Offshore Wind Accelerator