We recently explored the possibilities of connecting offshore wind power to the mainland grid under Fingrid’s responsibility. We initially identified six areas where it would be possible to connect offshore wind power, with a total potential capacity exceeding that of the current nuclear power production. In a consultation organised for customers, Fingrid’s study was welcomed and seen as an initiative that improves predictability.
In November, Fingrid will publish an updated study presenting the preliminary connection points for offshore wind power at the substation level, based on consultation feedback.
In the consultation responses, we were asked whether the main grid could be extended offshore and if Fingrid’s responsibility for building and maintaining the mainland grid could also cover the offshore grid – including the planning, permitting, construction, and maintenance of connection lines for offshore wind power projects. According to current practice, the offshore developer is responsible for connecting their power plant to the mainland grid substation, as is the case with other connecting projects.
The current practice works well from the perspective of both consumers and offshore developers. In Sweden, extending the main grid’s responsibility to offshore wind power collection lines was considered but has since been dismissed.
The current practice supports the independence of offshore wind power projects and reduces the risk of stranded assets. Coordinating two separate construction projects – offshore wind power and connection lines – with potential delays is challenging. The risk of stranded assets describes a situation where investments become economically unviable or obsolete before their expected lifespan. This occurs when there is a timing difference between the completion of the transmission network and production facilities, leading to underutilisation and financial losses.
Fingrid plans to invest approximately four billion euros over the next ten years to reinforce the main grid. These investments will enhance Finland’s position as a competitive destination for clean energy investments.
Fingrid’s focus on developing the mainland grid strengthens Finland’s internal electricity transmission capacity, aims to maintain a uniform electricity price area, and creates conditions for connecting new consumers and producers to the main grid in a technology-neutral manner.
Main grid connections to offshore areas would be a subsidy arrangement for a single production technology. Deviating from a market-based and technology-neutral approach would also require a political decision and a legislative change. The costs of the offshore grid would be borne by all network users, ultimately by Finnish electricity consumers.
In offshore wind power, Finland’s competitive advantage is that potential production areas are close to the mainland, and their connection cable sections can likely be implemented with alternating current connections. An offshore grid that collects the production of multiple offshore wind farms with a significantly more expensive direct current connection would likely not achieve overall economic benefits in Finnish conditions.
There are also still technical challenges, significant supply constraints, and unresolved reliability issues related to direct current solutions. The technology of direct current circuit breakers and the integration of products from different manufacturers are still in the development stage and require product development. To ensure the reliability of the power system, the bundling of large production hubs is also limited to a maximum size of 1.3 GW.
In addition to offshore wind power, onshore wind power and industrial-scale solar power accelerate the green transition by meeting the growing electricity consumption driven by new consumption investments. Offshore wind power can play an important role in Finland’s pursuit of carbon neutrality goals and is an important part of the future of sustainable energy production.
Fingrid continues to work closely with project developers and strives to jointly develop practices, particularly in connection methods.
Viljami Yli-Hemminki
Specialist
Fingrid
