# The Hornsea Three Offshore Wind Farm Order 2020, Paragraph 3

Extent: E+W

(1) The total number of offshore electrical installations and offshore accommodation platforms shall not exceed 21, and shall consist of no more than—
(a) 12 offshore type 1 substations;
(b) four offshore type 2 substations;
(c) four offshore HVAC booster stations;
(d) six offshore subsea HVAC booster stations; and
(e) three offshore accommodation platforms.
(2) The dimensions of any offshore type 1 substation forming part of the authorised project must not exceed—
(a) 90 metres in height when measured from LAT;
(b) 100 metres in length; and
(c) 100 metres in width.
(3) The dimensions of any offshore type 2 substation forming part of the authorised project must not exceed—
(a) 110 metres in height when measured from LAT;
(b) 180 metres in length; and
(c) 90 metres in width.
(4) The dimensions of any offshore HVAC booster station forming part of the authorised project must not exceed—
(a) 90 metres in height when measured from LAT;
(b) 100 metres in length; and
(c) 100 metres in width.
(5) The dimensions of any offshore subsea HVAC booster station forming part of the authorised project must not exceed—
(a) 15 metres in height when measured from the seabed;
(b) 50 metres in length; and
(c) 50 metres in width.
(6) The dimensions of any offshore accommodation platform forming part of the authorised project must not exceed—
(a) 64 metres in height when measured from LAT;
(b) 60 metres in length; and
(c) 60 metres in width.
(7) Any bridge located between any offshore substation or accommodation platform shall be no longer than 100 metres.
(8) Offshore accommodation platform foundation structures forming part of the authorised project must be one of the following foundation options: monopile foundations, mono suction bucket foundations, jacket foundations, or gravity base foundations.
(9) Offshore installation foundation structures forming part of the authorised scheme must be one of the following foundation options—
(a) for offshore type 1 substations, offshore HVAC booster stations and offshore subsea HVAC booster stations either monopile foundations, mono suction bucket foundations, jacket foundations, gravity base foundations, jacket foundations or box-type gravity base foundations; and
(b) for offshore type 2 substations, either monopile foundations, mono suction bucket foundations, jacket foundations, gravity base foundations, jacket foundations, box-type gravity base foundations, pontoon gravity base 1 foundations, or pontoon gravity base 2 foundations.
(10) No offshore installation or offshore accommodation platform—
(a) jacket foundation employing pin piles forming part of the authorised project shall have a pin pile diameter of greater than 4 metres; and
(b) monopile foundation forming part of the authorised project shall have a diameter greater than 15 metres.
(11) The total seabed footprint area for offshore accommodation platform foundations must not exceed—
(a) 8,836 square metres excluding scour protection; and
(b) 28,628 square metres including scour protection.
(12) The total seabed footprint area for offshore electrical installation foundations must not exceed—
(a) 138,900 square metres excluding scour protection; and
(b) 267,900 square metres including scour protection.

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Source: https://www.legislation.gov.uk/uksi/2020/1656/schedule/1/paragraph/3 (the official version)
Page: https://openlegislation.uk/hornsea-three-offshore-wind-farm-order-2020/schedule-1/paragraph-3
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.