# The Hornsea One Offshore Wind Farm Order 2014, Paragraph 5: Design parameters

Extent: E+W+S

(1) The licence-holder must in fixing to the seabed any structures comprised in Works Nos. 4 and 5 use one of the following methods—
(a) monopile foundations;
(b) jacket foundations supported by piles; or
(c) gravity base foundations.
(2) The licence-holder must not use the monopile foundation method or any other method which includes braced monopiles to fix to the seabed any offshore HVDC converter station.
(3) The following parameters apply in respect of the foundation methods used to fix offshore HVAC collector substations comprised in Work No. 4 to the seabed—
(a) where monopile foundations are used—
(i) the area occupied by the foundations and the scour protection for each individual structure must not exceed 1,419 m2;
(ii) the diameter of each foundation must not exceed 8.5 metres;
(b) where jacket foundations (driven/drilled piles) are used—
(i) the area occupied by the foundations and the scour protection for each individual structure must not exceed 1,924 m2;
(ii) the number of piles per jacket must not exceed eight;
(iii) the diameter of each pile must not exceed 3.5 metres;
(c) where jacket foundations (suction piles) are used—
(i) the area occupied by the foundations and the scour protection for each individual structure must not exceed 12,723 m2;
(ii) the number of piles per jacket must not exceed eight;
(iii) the diameter of each pile must not exceed 15 metres;
(d) where gravity base foundations are used—
(i) the area occupied by the foundations and the scour protection for each individual structure must not exceed 6,362 m2;
(ii) the seabed levelling diameter must not exceed 70 metres;
(iii) the cone diameter must not exceed 50 metres at its base.
(4) The following parameters apply in respect of the foundation methods used to fix offshore HVDC converter stations comprised in Work No. 4 to the seabed—
(a) where jacket foundations (driven/drilled piles) are used—
(i) the area occupied by the foundations and the scour protection for each individual structure must not exceed 4,330 m2;
(ii) the number of piles per jacket must not exceed 18;
(iii) the diameter of each pile must not exceed 3.5 metres;
(b) where jacket foundations (suction piles) are used—
(i) the area occupied by the foundations and the scour protection for each individual structure must not exceed 12,723 m2;
(ii) the number of piles per jacket must not exceed eight;
(iii) the diameter of each pile must not exceed 15 metres;
(c) where gravity base foundations are used—
(i) the area occupied by the foundations and the scour protection for each individual structure must not exceed 19,500 m2;
(ii) the number of pontoons for each individual structure must not exceed two;
(iii) the pontoons must not exceed 110 metres in length or 35 metres in width.
(5) The following parameters apply in respect of the foundation methods used to fix the offshore reactive compensation substation comprised in Work No. 5 to the seabed—
(a) where monopile foundations are used—
(i) the area occupied by the foundations and the scour protection must not exceed 1,419 m2;
(ii) the diameter of each foundation must not exceed 8.5 metres;
(b) where jacket foundations (driven/drilled piles) are used—
(i) the area occupied by the foundations and the scour protection must not exceed 1,414 m2;
(ii) the number of piles per jacket must not exceed eight;
(iii) the diameter of each pile must not exceed three metres;
(c) where jacket foundations (suction piles) are used—
(i) the area occupied by the foundations and the scour protection must not exceed 6,362 m2;
(ii) the number of piles per jacket must not exceed eight;
(iii) the diameter of each pile must not exceed 15 metres;
(d) where gravity base foundations are used—
(i) the area occupied by the foundations and the scour protection for each individual structure must not exceed 6,362 m2;
(ii) the seabed levelling diameter must not exceed 70 metres;
(iii) the cone diameter must not exceed 50 metres at its base.

---
Source: https://www.legislation.gov.uk/uksi/2014/3331/schedule/11/part/2/paragraph/5 (the official version)
Page: https://openlegislation.uk/hornsea-one-offshore-wind-farm-order-2014/schedule-11/part-2/paragraph-5
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.