Scope
Reference
10244
Description
SSEN Transmission is the licence holder for the transmission system in the north of Scotland. To meet the government's target for renewable generation, and for the development of the existing infrastructure, significant work is being undertaken on the transmission system. This work includes the building and rebuilding of overhead lines, the development of grid substations, the construction of HVDC converter and cable systems, and the construction of FACTS devices. The projects and work being undertaken are in line with the NESO (National Electric System Operator) published Holistic Network Design (HND, Pathway to 2030 and Beyond 2030) reports. SSEN Transmission is responsible for delivering the complex technology and network solutions relating to any Scottish Island or network solutions with offshore assets. Particularly, any electricity system transmission infrastructure, either offshore or onshore, including HVDC, FACTs, AC networks, cable systems, and offshore installations
The purpose of establishing this Services Framework is to ensure SSEN Transmission has access to a range of specialist engineering services.
The Services will include but not be limited to engineering competencies related to engineering management, engineering drawings, plant/equipment/system specification, electrical design, civil design, offshore installation design, offshore works, construction-site support, installation support, commissioning support, consent related works, engineering compliance, risk management, risk analysis, and design assurance.
The Consultant will be able to provide support during all project stages including concept, option selection, FEED, detailed design, manufacturing, testing, construction, installation, and commissioning stages.
The Services will be Lotted.
Lot 1: HVDC & FACTS: Expertise in all aspects of HVDC and FACTS devices.
Lot 2 :Cable Systems: Expertise in HV Cable Systems, covering both AC and DC technology for land and submarine applications.
Lot 3; AC Networks: Expertise in all aspects of AC Networks.
Lot 4: Offshore and Subsea Services: Expertise in preparing requirements and specification documents to provide technical direction and governance for the design, delivery, operation, maintenance, and decommissioning of offshore substation installations.
Commercial tool
Establishes a framework
Total value (estimated)
- £55,000,000 excluding VAT
- £66,000,000 including VAT
Above the relevant threshold
Contract dates (estimated)
- 10 December 2025 to 9 December 2028
- Possible extension to 9 December 2030
- 5 years
Description of possible extension:
2 x 12 months extensions
Main procurement category
Services
CPV classifications
- 71300000 - Engineering services
- 71320000 - Engineering design services
- 71356000 - Technical services
Contract locations
- UK - United Kingdom
Lot 1. HVDC & FACTS
Description
Expertise for all aspects of HVDC & FACTS devices including but
not limited to:
(1) System design,
(2) Network & system studies,
(3) Earthing system design,
(4) Station / Equipment layout design,
(5) Plant & Equipment design / testing,
(6) DC Control & Protection design and settings development,
(7) DC Control & Protection system testing using PSCAD and RSCAD/RTDS,
(8) AC & DC Control & Protection interfacing and integration,
(9) AC Protection & Control scheme designAC Protection & Control setting calculation including short-circuit modelling and
calculations,
(11) Operator interfaces & SCADA systems,
(12) Auxiliary power systems,
(13) Secondary mechanical & electrical systems,
(14) Commissioning and commissioning management, and
(15) Operations & maintenance.
Lot value (estimated)
- £55,000,000 excluding VAT
- £66,000,000 including VAT
Framework lot values may be shared with other lots
Same for all lots
CPV classifications, contract locations and contract dates are shown in the Scope section, because they are the same for all lots.
Lot 2. Cable Systems
Description
Expertise for HV Cable Systems: This scope pertains to AC and DC
technology, for land and submarine applications.
(1) Cable system design (i.e., thermal rating calculations using both analytical and finite
element methods, induced voltages / currents, electro-magnetic fields, etc),
(2) Cable routing design and risk assessment,
(3) Installation design (i.e., pulling tensions, thermo-mechanical & marine engineering
calculations),
(4) Mechanical protection design,
(5) Monitoring & communication fibre optic cable system design,
(6) Testing and test witnessing (factory and site),
(7) Site and vessel representation for installation activities,
(8) Factory audit (quality & technical),
(9) Failure investigation and root cause analysis (RCA),
(10) Reliability, availability & maintainability analysis,
(11) Operations & maintenance strategy and planning,
(12) Technical training to Employer's personnel,
(13) Diagnosis, analysis, and interpretation of cable system health & integrity based on
monitoring data acquired from field.
Lot value (estimated)
- £55,000,000 excluding VAT
- £66,000,000 including VAT
Framework lot values may be shared with other lots
Same for all lots
CPV classifications, contract locations and contract dates are shown in the Scope section, because they are the same for all lots.
Lot 3. AC Networks
Description
Expertise for all aspects of AC Networks including but not limited
to:
(1) Station design,
(2) Earthing system design,
(3) Plant & Equipment design / testingProtection & Control scheme design,
(5) Protection & Control setting calculation including short-circuit modelling and
calculations,
(6) Protection & Control system testing,
(7) Operator interfaces & SCADA systems,
(8) Overhead line design, consenting, and installation,
(9) Auxiliary power systems,
(10) Secondary mechanical & electrical systems,
(11) Commissioning and commissioning management, and
(12) Operations & maintenance
Lot value (estimated)
- £55,000,000 excluding VAT
- £66,000,000 including VAT
Framework lot values may be shared with other lots
Same for all lots
CPV classifications, contract locations and contract dates are shown in the Scope section, because they are the same for all lots.
Lot 4. Offshore and Subsea Services
Description
Expertise for all aspects of preparation of requirements &
specification documents to provide technical direction and governance for design, delivery,
operation, maintenance, and decommissioning of offshore substation installations
including but not limited to:
(1) Site selection and desktop studies for option selection stage,
(2) Cable routing design and selection including burial risk assessment (CBRA),
(3) Unexploded ordinance (UXO) survey and risk assessment,
(4) Cable protection system (CPS) design and analysis,
(5) On-bottom stability and free span analysis for subsea cable installation,
(6) Burial assessment study (BAS) for subsea cable installation,
(7) Design, feasibility and risk assessment for horizontal directional drilling (HDD),
(8) Corrosion analysis for subsea cable installation,
(9) Loadout, spooling, unspooling of subsea cable systems,
(10) Jacket primary & topside secondary structural design,
(11) Pile foundation and grouted connection for jacket sleeved piles,
(12) Geotechnical ground modelling and interpretation (structures, piles, and subsea
cable installation)
(13) Metocean interpretation for structural design jacket & topside,
(14) Fabrication, transportation, and installation studies (HLV & float over options),
(15) Material, fabrication, corrosion, & protection design for topside and substructure,
(16) LV electrical design for ducting, cable routing and cable cabinets, interfacing with
topside structural design
(17)Lifecycle and condition monitoring for jacket primary and secondary topside
structures,
(18) Operations and maintenance requirements for complete offshore substation asset,
(19) Design risk management, from concept design through to decommissioning,
(20) Decommissioning, and
(21) Design verification and certification support
Lot value (estimated)
- £55,000,000 excluding VAT
- £66,000,000 including VAT
Framework lot values may be shared with other lots
Same for all lots
CPV classifications, contract locations and contract dates are shown in the Scope section, because they are the same for all lots.
Framework
Maximum number of suppliers
Unlimited
Maximum percentage fee charged to suppliers
0%
Framework operation description
Detailed in PQQ / ITT documentation
Award method when using the framework
Either with or without competition
Contracting authorities that may use the framework
Establishing party only
Participation
Legal and financial capacity conditions of participation
Lot 1. HVDC & FACTS
Lot 2. Cable Systems
Lot 3. AC Networks
Lot 4. Offshore and Subsea Services
As per PQQ documentation
Technical ability conditions of participation
Lot 1. HVDC & FACTS
Lot 2. Cable Systems
Lot 3. AC Networks
Lot 4. Offshore and Subsea Services
As per PQQ documentation
Particular suitability
Lot 1. HVDC & FACTS
Lot 2. Cable Systems
Lot 3. AC Networks
Lot 4. Offshore and Subsea Services
Small and medium-sized enterprises (SME)
Submission
Enquiry deadline
18 September 2025, 12:00pm
Submission type
Requests to participate
Deadline for requests to participate
25 September 2025, 12:00pm
Submission address and any special instructions
Scottish Hydro Electric Transmission plc invite interested suppliers to view the PQQ Documents on our Jaggaer eprocurement system under "Current Opportunities" here:
https://sse.app.jaggaer.com/esop/guest/go/opportunity/detail?opportunityId=436
Full details of the service required and how to respond to the Pre-Qualification Questionnaire can be found on that page
Tenders may be submitted electronically
Yes
Languages that may be used for submission
English
Award decision date (estimated)
24 November 2025
Award criteria
| Name | Type |
|---|---|
| As per PQQ documentation | Quality |
Weighting description
As per PQQ documentation
Other information
Conflicts assessment prepared/revised
Yes
Procedure
Procedure type
Competitive flexible procedure
Special regime
Utilities
Competitive flexible procedure description
PQQ to be issued - Two step procedure under PA23 utilising Jaggaer / Find a tender. Following PQQ evaluation, down selection will be made to move to
ITT stage. Awards will be made per Lot. Total of four (4) available Lots
Contracting authority
SCOTTISH HYDRO ELECTRIC TRANSMISSION PLC
- Companies House: SC213461
Inveralmond House, 200 Dunkeld Road
Perth
PH1 3AQ
United Kingdom
Region: UKM77 - Perth & Kinross and Stirling
Organisation type: Private utility