Iddenshall

Project Overview

DACI delivered a coordinated technical package that helped de-risk the connection, operation and safety case for a large PV solar farm development.

The project required more than a conventional earthing design. Alongside the PV farm earthing design, DACI considered auxiliary 11kV infrastructure, nearby third-party receptors, livestock exposure, existing high-pressure gas main and lightning risk across the development area.

This integrated approach provided a practical design basis for the renewable generation site while helping stakeholders understand safety, compliance and infrastructure-interface risks before construction and energisation.

Our Scope

DACI Scope of Work

Soil Resistivity Testing — Ground investigation data to support accurate modelling and earthing design development.

PV Farm Earthing Design — Earthing strategy for generation infrastructure, collector systems and site-wide interfaces.

11kV Auxiliary Earthing — Auxiliary supply earthing design with safety assessment for nearby houses and livestock.

Third-Party Safety Review — Evaluation of exposure risks beyond the site boundary, including people, property and animals.

Electromagnetic Interference Study — Assessment of interference risk onto an existing high-pressure gas main crossing or adjacent to the site.

Lightning Risk Assessment — Review of lightning exposure to support protection strategy and operational resilience.

Engineering Challenges

Balancing Renewable Generation, Safety and Utility Interfaces

PV solar farms can present complex earthing challenges because the electrical network, metallic infrastructure, fencing, auxiliary supplies and buried third-party utilities may interact under fault and transient conditions. For this project, the presence of nearby houses, livestock and a high-pressure gas main required a broader safety-led approach.

Critical Risk Third-Party Safety

Nearby residential properties and livestock introduced sensitive third-party exposure considerations. Touch, step and transferred-potential risks required careful assessment beyond the site boundary.

High Priority Gas Main Interference

An existing high-pressure gas main required specialist electromagnetic interference assessment, confirming low impact from inductive, conductive and fault-related effects of the electrical installation.

High Complexity Site-Wide Earthing Integration

The extensive PV farm layout required coordinated earthing across generation equipment, metallic structures, fencing, collector systems and the 11kV auxiliary network.

Multi-Disciplinary Lightning and Electrical Safety

The earthing solution accounted for power-frequency faults and lightning risks, requiring coordination across site earthing, auxiliary systems, lightning protection and third-party infrastructure. A lightning risk assessment was also included.

DACI Solution

DACI Approach

Developed a representative soil model from soil resistivity testing results.
Assessed the earthing requirements for the PV farm and associated 11kV auxiliary infrastructure.
Reviewed touch, step and transferred potential risks for third-party receptors, including existing houses and livestock.
Evaluated electromagnetic interference risk associated with the existing high-pressure gas main.
Completed lightning risk assessment to inform protection and resilience measures.
Combined findings into a coherent design and safety narrative suitable for stakeholder review.

Outcome

The completed package gave the project team a stronger technical basis for progressing the renewable energy scheme. By treating earthing, auxiliary systems, third-party safety, pipeline interference and lightning risk as connected issues, DACI helped reduce uncertainty and support a safer, more resilient design.

Value Delivered

Safety assurance — Assessment considered touch, step and third-party exposure risks for nearby properties and livestock.
Network integration — Earthing design supported PV farm infrastructure and 11kV auxiliary systems.
Utility interface — Electromagnetic interference assessment addressed interaction with an existing high-pressure gas main.
Resilience — Lightning risk assessment supported protection strategy and operational continuity.

Wider Impact

The work demonstrates DACI's ability to support renewable generation projects with practical, multi-disciplinary earthing expertise from field testing through to design assurance and specialist risk assessment.

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