Danes Seek Permits to Start Hesselø Investigations

The Danish Energy Agency has sent a draft permit for preliminary offshore and onshore studies related to the Hesselø offshore wind project for consultation with the relevant authorities.

Danish Energy Agency

The feasibility study permit will give the transmission system operator Energinet, which is to be responsible for the investigations, the right to collect relevant information about the proposed site in the Danish Baltic Sea.

The feasibility studies consist of environmental biological, geophysical, and geotechnical investigations with boreholes, as well as the 3D mapping of the seabed.

Hesselø is the second of the three offshore wind farms proposed in the Energy Agreement 2018, the first being the Thor project.

The wind farm is located north of Sealand in Kattegat, in Hesselø Bay, at a distance of 30 kilometres from Sealand and around 20 kilometres from the Hesselø island.

Initially, Hesselø was scheduled for commissioning in 2028, but according to the recently approved Climate Action Plan, both Hesselø and Thor will be commissioned in 2027.

Denmark plans to start the tendering procedure for the development of the wind farm in 2021 and select the winner in 2022.

The wind farm will have an installed capacity of between 800 MW and 1,200 MW and can thus potentially become the largest offshore wind farm in Denmark, depending on the capacity that the winner of the tender chooses to install.

The authority consultation includes parties with interests at sea as well as municipalities with a view of the wind farm, or those which could be affected by land cables. The deadline for comments is 17 September 2020.

The short deadline is due to Energinet having to have the feasibility study vessels sent out quickly before the weather becomes too harsh, the Danish Agency said. With the climate agreement’s goal that Hesselø must be completed in 2027, it is a prerequisite that the schedule for feasibility studies and tenders is compressed, the agency said.

Two Possible Land Cable Routes

The permit applies to surveys for the areas at sea where the offshore wind farm itself is to be located. The permit also applies to studies of two possible routes to the cable that carries the power from the offshore wind farm to the Danish grid.

Danes Seek Permits to Start Hesselø Investigations
The area within the blue line is where Energinet will carry out feasibility studies for the Hesselø offshore wind farm. Source: Danish Energy Agency

The two possible landing routes that are being considered are a route from the offshore wind farm past Rørvig and Hundested at the mouth of Isefjord and down through Isefjord to the landing point at Kyndbyværket; and a route from the offshore wind farm to the landing point at Gilbjerg Hoved west of Gilleleje Harbor.

The wind farm will in both cases be connected to the transformer station in Hove.

In parallel with the authority consultation of the feasibility study permit, the Danish Energy Agency and Energinet will analyze which of the two landing points is the best solution overall. This means that the Danish Energy Agency will probably issue the final permit with only the selected landing route. Energinet can then begin the preliminary investigations.

Environmental Impact Assessment

Later in the year, Energinet will initiate an environmental impact assessment (EIA) of the cable corridor and technical facilities on land, as well as prepare the overall strategic environmental assessment of the project. The hearings on these assessments are scheduled to take place in mid-2022.