Delivering full 132/33 kV infrastructure, protection, SCADA and turbine array energisation for 24 Vestas V136 turbines
Project Snapshot
| Client | Boralex (in partnership with R.J. McLeod) |
| Location | Limekiln Wind Farm, Reay, Thurso, KW14 7RE |
| Project Value | £7.4 million |
| Project Duration | Oct 2023 – Apr 2025 |
| Market Sector | Onshore Wind (EBoP) |
| Services Delivered | Full Electrical Balance of Plant (EBoP) |
| Powersystems Fact | Powersystems has connected over 24% of all UK wind farms, making Limekiln another successful collaboration with Boralex and R.J. McLeod. |
Limekiln 108 MW Wind Farm Case Study
Download the full Limekiln Wind Farm Case Study to explore how Powersystems delivered the complete 132/33 kV Electrical Balance of Plant for this 108 MW onshore development. The PDF provides a clear overview of our transformer, switchgear and cabling works, including 25 km of 33 kV circuits, protection and SCADA integration, and full commissioning in partnership with Boralex and R.J. McLeod. Ideal for engineers, developers and stakeholders seeking deeper insight into a major wind farm project powering around 100,000 homes and supporting Scotland’s net‑zero ambitions.
Client & Site Background
Limekiln Wind Farm is the first UK wind project developed by Boralex, consisting of 24 Vestas V136 turbines with a total installed capacity of 108 MW.
Located south of Reay in Caithness, the wind farm supplies enough clean electricity to power around 100,000 households.
The site received consent from the Scottish Government to construct and operate the wind farm, with long-term operation now forming part of Scotland’s renewable energy expansion strategy.
Powersystems was appointed as the Electrical Balance of Plant (EBoP) contractor, responsible for full HV and MV system delivery, including design, construction, testing, commissioning and energisation.
The Challenge
The project required Powersystems to:
- Deliver a complete 132 kV–33 kV electrical system across a remote and exposed Caithness site
- Integrate with SSEN’s 132 kV transmission network, requiring detailed interface management
- Install 25 km of 33 kV cabling over challenging terrain
- Commission a 120 MVA grid transformer with 145 kV primary equipment
- Meet energisation deadlines despite a condensed construction window
- Ensure SCADA, protection and control systems aligned with SSEN and National Grid compliance
Our Engineering Solution
Powersystems delivered a full turnkey EBoP engineering solution, combining HV, LV, protection and control systems.
132 kV Substation Infrastructure
- 120 MVA, 33/132 kV grid transformer (SSEN‑compliant)
- 145 kV dead‑tank circuit breaker, busbars and overhead conductors
- 132 kV VTs, disconnectors and earth switches
- 33/0.415 kV auxiliary earthing transformer
- Complete 132/33 kV protection schemes
- Civil integration and transformer bund design
33 kV Wind Farm Electrical Systems
- 8‑panel Schneider WS 33 kV switchboard (protection relays, busbar VTs)
- 25 km of 33 kV cabling, jointing and terminations
- Turbine and substation earthing systems
- LV, control and communication cabling
- Compound lighting, LV distribution and panel design
- Fibre‑optic SCADA integration
SCADA, Controls & Monitoring
- Turbine control integration
- SSEN interface for grid protection
- National Grid testing panel
- Telemetry, alarms and full monitoring suite
Project Process
- Early 2023 — Civil works begin under R.J. McLeod
- Oct 2023 — Powersystems mobilises to site
- 2023–2024 — Substation construction, cabling, transformer installation
- 20 November 2024 — First energisation of main substation and initial array
- 2024–2025 — SCADA integration, protection testing, turbine commissioning
- April 2025 — Full site energisation and handover
Powersystems maintained consistent SHEQ processes, daily coordination meetings and proactive programme management throughout.
Project Facts & Figures
- 24 × 4.5 MW Vestas turbines → 108 MW installed capacity
- 1 × 120 MVA 33/132 kV grid transformer
- 1 × 132 kV dead‑tank circuit breaker
- 25 km of 33 kV cabling installed
- 1 × 33/0.415 kV auxiliary earthing transformer
- NERS‑accredited ICP
- Power for ~100,000 homes
Technical Specifications
High Voltage (132 kV) System
- 120 MVA transformer
- 145 kV VTs, CTs, earth switches & disconnectors
- Dead‑tank 132 kV circuit breaker
- Overhead busbar configuration
- Full 132 kV earthing & bonding
33 kV System
- 8‑panel Schneider WS switchboard
- 25 km of 33 kV aluminium cables
- Turbine array cabling in five routes
- Protection relays configured for SSEN grid compliance
Protection & SCADA
- Load flow, fault level, harmonic and P28 flicker studies
- G5.5 harmonic analysis
- RMS (Grid Code) compliance study
- Power quality metering
- Central SCADA integration
Building & LV Systems
- Lighting, heating, small power
- Fire & intruder alarms
- Auxiliary transformer & LV panels
- Compound lighting & control system
Partnerships
- Boralex — Developer and owner (first UK wind project)
- R.J. McLeod — Principal Civil Engineering Contractor
- SSEN Transmission — 132 kV grid connection (TNO)
- Powersystems — Electrical Balance of Plant Contractor
Public confirmation of Boralex’s role and turbine configuration is supported by project data.
Powersystems’ involvement and EBoP scope are confirmed in the official update.
Key Risks & Mitigations
- High‑voltage interface with SSEN (132 kV)
Mitigation: Early coordination, protection scheme validation, staged commissioning. - Challenging remote Highland terrain
Mitigation: Optimised cable routing; robust earthing across variable geology. - Condensed programme
Mitigation: Accelerated installation; parallel workstreams; clear reporting. - Environmental constraints
Mitigation: Low‑impact trenching; controlled vehicle movements; protected habitat zones.
Environmental Considerations
- 108 MW of clean, renewable generation
- Avoids ~62,500 tonnes of CO₂ annually (based on public project data)
- Supports Scotland’s 2045 net‑zero goals
- Modern, low‑loss electrical infrastructure
- Long‑term optimal land use following forestry and rural estate management
Economic & Social Value
- Provides renewable electricity for ~100,000 households
- Significant Scottish supply‑chain participation
- Supports ~720 jobs across Scotland during construction
- Long-term community benefit fund
- Boosts regional energy security
Future Prospects
Limekiln is engineered for long-term performance, grid compliance and operational resilience.
The project strengthens Boralex’s presence in the UK and cements Powersystems’ position as a leading partner for 132/33 kV onshore wind projects.
Related Projects
- Camster II 36 MW
- North Kyle 212 MW
- Sandy Knowe 86.4 MW
- Glen Kyllachy 48.5 MW
- Sneddon Law 30 MW
Delivering a 108 MW wind farm or high voltage EBoP project?
Talk to Powersystems about HV design, 132/33 kV substations, cabling, SCADA and grid‑connection delivery for utility‑scale renewables.