Our projects
Engineering Excellence Across the Energy Sector
At TES Limited, we pride ourselves on delivering robust, high-voltage engineering solutions that power the UK’s critical infrastructure. With decades of experience in the energy sector, our portfolio demonstrates a diverse range of successful projects, from complex transmission network upgrades to renewable energy integration and private network reinforcement.
Detail Projects
Case Studies
Thorpe Marsh 400kV MESH Corner Feeder, MESH Corner, and MESH DAR Protection Replacement
This 400kV substation was constructed with Air Insulated Switchgear and consisted of a four-switch mesh with 400/275kV SGT’s on mesh corners 1 & 3, a 400kV Shunt Reactor on Mesh Corner 2, and an additional 400kV Circuit Breaker on Mesh Corner 3.
The TES scope of work consisted of the replacement of the entire protection systems on 3 Mesh Corners and replacement of the MESH DAR protection using an overlay scheme that required complex interface engineering. This overlay methodology was implemented to help assist with stringent network constraints.
The detailed scope of work that was carried out by TES was as follows:
- Site specific scheme design utilising NICAP type registered standard bay solutions for the hub site and remote end substations
- Interfacing of new protection equipment into already installed equipment that is not being made redundant
- Red and Green multicore cable schedules and core sheets
- Removal of redundant line trap equipment
- Design of new protection front sheets for installation on site
- Protection settings calculations from given power system data
- Preparation of control system I/O information to facilitate multiple control system data base updates.
- Modification of existing protection and DAR schedules
- Protection relay configuration based on type registered standard bay solution
- Factory acceptance testing of new protection panels
- Marking up of existing and production of new drawings
- Site scanning of hub site and remote end drawings
- Site filing of as-built drawings
- Project management, Temporary Works Coordination and SHEQ management
Case Studies
South Shields 275kV Substation Protection and Control Replacement
The scope of works was to install new protection and control for the following: Feeder Protection (Blyth-Tynemouth & West Boldon circuits), SGT HV/LV Protection, Mesh Corner Protection, S10 Circuit Breaker Protection, Mesh DAR and SCS at South Shields 275kV Substation. This also included the remote end works at Blyth, Tynemouth, West Boldon 275kV Substations.
The Scope of work that was carried out by TES was as follows:
- Project management, Temporary Works Coordination and SHEQ management
- Document Control and CAD
- Design Intent Document
- Bill of Materials
- Site specific scheme design utilising Siemens PLC type registered standard bay solution
- New Panel General Arrangements and Wiring Diagrams
- Interfacing of new equipment into already installed equipment. Including wiring diagrams, core sheets, cable schedules and block cable diagrams
- IO and GEMs
- Protection relay configuration based on type registered standard bay solution
- Factory acceptance testing of new protection panels
- Construction Boxes
- Site filing of as built drawings
Case Studies
Elstree 400/132kV Clean Gas & SF₆ GIS Bay Extension
This project involved the extension of an existing 132kV GIS substation to accommodate two new customer circuits (UKPN Feeder 1 & 2) and an additional 400/132kV SGT bay to increase power capacity. New Protection & Control (P&C) engineering works were required across the existing 400kV GIS substation, the existing 132kV GIS substation, and the new 6‑bay 132kV clean‑gas extension building.
Transmission Engineering Services delivered the full protection engineering scope, including:
- Kit‑out of 2 skeleton bays in the existing 132kV GIS building for future feeders
- Conversion of a spare 400kV GIS bay into an SGT HV bay
- Engineering for 6 new bays at the clean‑gas extension:
- 2 × Feeder bays
- 1 × SGT LV bay
- 1 × Bus Coupler bay
- 2 × Bus Section bays
- Replacement and relocation of GIS earth switches
- 400/132kV new SGT and 275/132kV SGT replacement works
Protection & Control Engineering
- Site‑specific scheme design using NICAP type‑registered standard bay solutions
- Interfacing with existing electrical interlocking schemes and extending busbar protection to new bays
- Integration with the existing gas leakage monitoring system and development of a new system for extension bays
- Preparation of wiring diagrams and interfacing of new protection equipment with new plant
- Interfacing new protection equipment with existing non‑redundant systems
- Design and integration of PQM & HAM metering
- LVAC and DC load calculations, cable sizing, and trip/close coil voltage‑drop calculations.
- Preparation of BOM and review of relay panel, control panel, and LCC General Arrangement drawings
- Preparation and modification of cable schedules (multicore, fibre optic, patch cords, Harting plugs), cable block diagrams, and core sheets
- Preparation of control system I/O information to support multiple control system database updates
- Mark‑up of existing drawings and production of new drawings
- Removal of redundant equipment
- Support for DID preparation, key line diagrams, design review meetings, and site queries
- Site scanning of hub‑site drawings
Case Studies
132kV Manually Switched Capacitor Protection Replacement
Transmission Engineering Services.
At this 132kV substation our scope of work included the replacement of existing Mechanically Switched Capacitor main and back-up and tertiary protections on MSC3 Banks A, B & C. The existing Reyrolle DAD, DCD314A, RH03, ABB SPAJ160C and Alstom KCGG142 protections were replaced with new in-situ NICAP protection solutions.
The detailed scope of work that was carried out by TES was as follows:
- Site specific scheme design utilising NICAP type registered standard bay solutions.
- Interfacing of new protection equipment into already installed equipment that is not being made redundant
- Red and Green multicore cable schedules and core sheets
- Design of new protection front sheets for installation on site
- Protection settings calculations from given power system data
- Protection relay configuration based on type registered standard bay solution
- Factory acceptance testing of new protection tiers
- Marking up of existing and production of new drawings
- Site scanning of existing site drawings
- Site filing of as-built drawings
- Project management, CDM, Temporary Works Coordination and SHEQ management
- Preparation and submission of the Commissioning Switching Programme
Case Studies
Eye and Walpole 400/kV Synchronous Condenser
Eye and Walpole 400/kV Synchronous Condenser
This project involved installation of Synchronous condenser in two National Grid substations to provide dynamic reactive power support, voltage regulation and system strength to the transmission network.
Transmission Engineering Services delivered the full protection engineering scope, including:
Protection & Control Engineering
- Site‑specific scheme design using NICAP type‑registered standard bay solutions
- Preparation of electrical interlocking schemes
- Interface with syncon drawings from Germany
- Preparation of supplies pillar, CVT and interface cubicle drawing
- Preparation of schematic diagrams, wiring diagrams and interfacing of new protection equipment with new plant
- Design and integration of PQM metering
- Preparation of BOM and review of relay panel, CVT and Marshalling kiosk GA drawings
- Preparation of cable schedules (multicore, fibre optic & patch cords), cable block diagrams, and core sheets
- Preparation of control system I/O information to support multiple control system database updates
- Preparation of communication overview drawing
- Production of new drawings
- Support for DID preparation, key line diagrams, design review meetings, and site queries
Case Studies
Eastern Green Link 1
The scope of works was to install protection and control for the new Hawthorn Pit 400kV GIS Double Busbar Substation this included the following: SGT HV/LV Protection, Bus Coupler/Section Protection, Busbar Protection 1 & 2 and SCS. This also included the remote end works at Hawthorn Pit and Offerton 275kV Substations along with Norton 400kV Substation.
The Scope of work that was carried out by TES was as follows:
- Site specific scheme design utilising Siemens PLC and Hitachi type registered standard bay solution.
- Site specific design using Hitachi GIS LCC drawings.
- New Panel General Arrangements and Wiring Diagrams
- Interfacing of new equipment. Including wiring diagrams, core sheets, cable schedules and block cable diagrams
- IO and GEMs
- Cabling sizing calculations including trip and close coil calculations.
- Document Control and CAD