Complete high‑voltage Balance of Plant (BoP) and NGED grid connection for a major UK solar installation
Project Snapshot
| Project Detail | Information |
| Client | Innova |
| Location | Tolldish Hall Farm, Parrotts Grove, Coventry, CV2 1NR |
| Project Value | £2,730,154.96 |
| Project Duration | Contract: Jul 2024 • Construction: Jan 2025 • Energisation: Nov 2025 • Completion: Dec 2025 |
| Services | HV Electrical Infrastructure, 33 kV Grid Connection, Balance of Plant |
| Market Sector | Solar Farm – Renewable Energy |
| Installed Capacity | 25.2 MW |
| Connection Voltage | 33 kV |
| Powersystems Role | Full ICP design, installation, testing & commissioning for customer and DNO assets |
| Powersystems is an employee‑owned business and the UK’s first Lloyd’s accredited ICP, delivering high‑voltage engineering up to 400 kV |
Tolldish Hall 25.2 MW Solar Farm Case Study
Download the full Tolldish Hall Solar Farm Case Study — designed for engineers, developers and technical stakeholders. This summary outlines the 33 kV grid connection, NGED‑adopted substation, customer compounds, cable routes, transformer systems, protection and SCADA works delivered by Powersystems. The full document provides detailed insight into HV design, civil construction, commissioning, environmental strategy and network integration for a 25.2 MW solar farm.
Client & Site Background
Innova is one of the UK’s leading independent solar and energy storage developers. The Tolldish Hall Solar Farm expands Innova’s clean‑energy portfolio, generating 25.2 MW of renewable capacity and exporting directly into NGED’s 33 kV network.
Located southwest of Tolldish Hall, the solar farm generates enough electricity to power 7,091 homes, avoiding approximately 5,550 tonnes of CO₂ annually.
The project was delivered without government subsidy, demonstrating the commercial maturity and cost‑competitiveness of UK solar generation.
The Challenge
Innova required a full, end‑to‑end HV solution comprising:
- A new 33 kV NGED grid connection
- A 1,700 m 33 kV underground cable route through public highways
- Construction of two customer 33 kV substation compounds
- Design & build of a new NGED 33 kV steel substation enclosure
- Integration of a 33 kV switchboard, transformer systems and metering
- Full protection, SCADA, DSM/PQM and constraint signalling
- Commissioning and energisation within fixed programme deadlines
Powersystems were appointed to deliver all contestable and customer‑side HV infrastructure.
Our Engineering Solution
Powersystems delivered a complete design‑and‑build HV BoP solution, including:
NGED 33 kV Infrastructure Delivered
- Full design, procurement & installation of the 1,750 m 33 kV cable
- Civil design and build of the NGED 33 kV substation enclosure
- Installation of:
- Siemens NXPLUS 33 kV switchboard
- NGED incomer & feeder breakers
- 33 kV voltage transformers
- 110 V & 48 V battery chargers
- G99 PQM/DSM panel
- IBOX RTU
- 2 × 3 × 1c 300 mm² AL 33 kV XLPE circuits
- Full DNO protection, control & interface systems
- Earthing, LV systems, control, signal & comms cabling
Customer‑Side 33 kV Infrastructure Delivered
- Civil design & construction of two customer 33 kV compounds
- Ormazabal CPG.0.V 33 kV switchboards
- Customer/NGED incomer breakers
- Fire & intruder systems
- Auxiliary transformer and LV systems
- DSM/PQM panel
- 50 kVA 33 kV/415 V auxiliary transformer
- 33 kV CVTs, VTs and 300 mm² cable systems
- Earthing, LV, control, signal & comms installation
This fully integrated system delivers a resilient, compliant and future‑proof export connection into NGED’s network.
Project Process
- Civil mobilisation and compound preparation (Jan 2025)
- 33 kV cable route installation through highway network (completed May 2025)
- Foundations and earthing installation (June 2025)
- Delivery of NGED and customer substation enclosures (July 2025)
- Installation of HV plant, switchgear and auxiliary systems (Aug–Oct 2025)
- Commissioning programme (Aug–Nov 2025)
- NGED energisation (Nov 2025)
- Customer energisation & handover (Dec 2025)
Project Facts & Figures
- Installed Capacity: 25.2 MW
- Connection Voltage: 33 kV
- 33 kV Cabling Installed: 1,750 m
- CO₂ reduction: ~60% lower than fossil fuels
- NERS Accredited ICP: Yes
Partnerships
Delivered on behalf of:
- Innova – Renewable energy developer
- Close coordination with Coventry City Council & Warwickshire County Council
- Grid integration with NGED (DNO)
- Lydon Contracting – The Civil Contractor
- Morgan Marine – DNO steel enclosure
Powersystems’ extensive experience with 33 kV export connections played a crucial role in timely delivery.
Key Risks & Mitigations
- Highway constraints along 1.7 km cable route – Mitigation: Detailed traffic management & trench sequencing.
- DNO approval bottlenecks -Mitigation: Early NGED design submissions and proactive interface management.
- Wet‑season civil works – Mitigation: Ground stabilisation & weather‑adaptive scheduling.
- Long‑lead switchgear procurement -Mitigation: Early manufacturer engagement ensured on‑time delivery.
- Environmental risk -Mitigation: Biodiversity enhancements, net‑zero alignment and strict waste control.
Environmental Considerations
- Clean energy for 7,091 homes
- Annual CO₂ savings of 5,550 tonnes
- Habitat enhancements delivering measurable biodiversity uplift
- Sustainable procurement & reduced construction emissions
Economic & Social Value
- Supports local jobs and supply chains
- Reinforces regional grid resilience
- Indirectly supports commercial and industrial demand
- Enables long‑term investment in local infrastructure
Challenges & Lessons Learned
- Wet‑season construction required flexible programming
- Long‑lead procurement emphasised need for early specification
- Cross‑stakeholder communication was essential in mitigating delays
- Importance of coordinated NGED, contractor and client workflows
Future Prospects
The Tolldish Hall Solar Farm now exports 25.2 MW of renewable energy to NGED’s network, supporting regional decarbonisation and the UK’s Net Zero 2050 target. The project was delivered on time, on budget, and to all technical, regulatory and environmental standards.
Related Projects
- Crimscote Solar Farm – 45 MW
- South Fambridge Solar Farm – 43.3 MW
- Kemble Solar – 49 MW
- Rag Lane Solar – 49 MW
Powersystems provide high voltage grid connections and Balance of Plant solutions for solar, wind and flexible generation projects across the UK.
Speak to our engineering team today.