Integrating 15 Vestas turbines, 33 kV substation and SPEN grid connection to power ~29,600 homes
Project Snapshot
| Client | Community Windpower Ltd (CWL) |
|---|---|
| Location | East Ayrshire, Scotland — ~5 km north of Galston, ~9 km east of Kilmarnock; adjacent to Whitelee Wind Farm |
| Project Value | £2.1 million |
| Project Duration | 14 months — completed end of January 2024 |
| Market Sector | Renewable Energy — Onshore Wind |
| Services Delivered | Electrical Balance of Plant (EBoP): 33 kV cabling, jointing/terminations, substation LV fit‑out, 33 kV switchgear, SCADA/control cabling, earthing, STATCOM integration, SPEN interface |
| DNO | SP Energy Networks (SPEN) |
| Installed Capacity | 30 MW — 15 × 2 MW turbines (two arrays) |
| Connection Voltage | 33 kV |
| Energy Equivalent | Supplies electricity for ~29,600 households |
Client & Site Background
Sneddon Law Community Wind Farm sits in East Ayrshire, adjacent to the renowned Whitelee Wind Farm. Developed by Community Windpower Ltd, the project reinforces Scotland’s renewable energy leadership and delivers tangible community and economic benefits alongside low‑carbon power generation.
The Challenge
- Deliver a complete EBoP package against a tight programme, coordinating closely with SPEN, the civil contractor and the turbine OEM.
- Manage challenging peaty ground conditions, ensuring safe installation, reliable earthing and long‑term integrity of underground assets.
- Integrate two turbine arrays into a single 33 kV substation with robust protection, control and SCADA for real‑time monitoring and grid compliance.
Our Engineering Solution
Powersystems provided end‑to‑end EBoP delivery, including:
- 33 kV substation systems: 5‑panel Schneider WS switchboard, interface/control/protection panels, LV fit‑out (small power, lighting, SPEN room).
- Grid interface to SPEN 33 kV network, including all 33 kV jointing and terminations.
- On‑site 33 kV cable network linking 15 turbines to the substation across both arrays (approx. 28,840 m of cabling).
- STATCOM integration (reactive power support; ~4 MVAR unit) to support voltage control and grid code performance.
- SCADA & control cabling for communications between SPEN, the client switchgear and Vestas equipment, with allowance for future National Grid requirements.
- Comprehensive earthing across the wind farm and substation compound.
Project Process
- Electrical design studies (HV & LV), grid‑code compliance and protection coordination.
- Early civils & rooms fit‑out to enable SPEN switchgear installation (Dec 2022–Feb 2023).
- Array 2 33 kV cable installation (mid‑Mar 2023) through peaty terrain with specialist handling.
- Earthing rollout — by June 2023, 13 of 15 turbine earth mats installed and backfilled.
- Switchgear & controls — 5‑panel 33 kV Schneider WS installed/commissioned; multicore controls and SCADA cabling completed (mid‑Jul 2023).
- DNO energisation — SPEN 33 kV energisation 17 July 2023; turbine terminations sequenced late July; Array 2 energisation targeted mid‑August.
- STATCOM delivery & commissioning support (Aug 2023 onward).
- Final integration & testing — staged energisation managed by Powersystems SAP and PM.
- Completion — all on‑site works finished end‑January 2024.
Project Facts & Figures
- 15 turbines × 2 MW (Vestas) → 30 MW total
- 33 kV connection to SPEN
- ~28,840 m of 33 kV on‑site cabling
- 5‑panel 33 kV Schneider WS switchboard
- ~4 MVAR STATCOM (dynamic reactive compensation)
- 50 kVA 33,000/230 V auxiliary transformer
- Power for ~29,600 homes equivalent
Technical Specifications
Primary Electrical Systems
- 33 kV Switchgear: 5‑panel Schneider WS within client switch room
- Auxiliary Supply: 50 kVA 33 kV/230 V single auxiliary transformer
- Reactive Support: STATCOM (~4 MVAR) for voltage regulation and grid compliance
- Protection & Control: Interface/control/protection panels; protection relays coordinated with SPEN
Cabling & Communications
- 33 kV cable network across both arrays, with jointing & terminations to SPEN standards
- Fibre‑optic backbone for SCADA and turbine communications
- Multicore control wiring between SPEN interface, client switchgear and Vestas systems
Earthing & Civil Interfaces
- Substation & turbine earthing systems designed and installed across site
- LV fit‑out of substation (lighting, small power, SPEN room readiness)
Partnerships
- Community Windpower Ltd (CWL) — Client & project owner
- RJ McLeod — Principal civil contractor
- SP Energy Networks (SPEN) — DNO interface and 33 kV network connection
- Vestas — Turbine OEM & interface
- CS Wind UK — Tower fabrication
- Powersystems — EBoP design, installation, testing, commissioning
Key Risks & Mitigations
- Peaty terrain & ground stability – Mitigation: Specialist trenching techniques, adapted bedding/backfill, rigorous earthing integrity checks.
- Environmental sensitivities (e.g., nesting birds) – Mitigation: Cable‑drum end covers during bird‑nesting season; method statements aligned to ecological constraints.
- High‑voltage safety & staged energisation – Mitigation: SAP‑controlled switching, formal Inspection & Test Plans (ITPs), remote open/close panel for controlled operations.
- Multistakeholder coordination (Civils, DNO, OEM) – Mitigation: Integrated programme, phased commissioning windows, daily interface meetings during critical works.
Environmental Considerations
- Biodiversity protection: Proactive measures to prevent nesting in cable drums during pulls.
- Reduced spill risk: Auxiliary transformer filled with MIDEL (biodegradable) oil and fully bunded.
- Decarbonisation impact: Clean power for ~29,600 households; supports Scotland’s net‑zero pathway through 2024+ operation.
Economic & Community Benefits
- Local supply chain engagement — >150 staff involved during construction, including local suppliers.
- Significant regional investment — Part of >£50 m spend linked to the wind farm development, supporting jobs and services.
- Community benefit funding — Annual community fund commitment aligned to installed capacity, supporting projects over the farm’s operational life.
Future Prospects
With Sneddon Law operational, the electrical infrastructure is configured for reliable long‑term performance, with SCADA‑enabled visibility for optimisation and straightforward integration of future upgrades as required by the client or grid operator.
Related Projects
- Onshore Wind — EBoP & Grid Connection (33 kV / 132 kV)
- Battery Energy Storage (BESS) — Grid Integration & Control
- Solar PV — HV Substations & Private Networks
Planning a new wind farm or EBoP upgrade?
Talk to Powersystems about 33 kV–132 kV grid connections, substation delivery and full EBoP integration for utility‑scale renewables.