This article draws on insights from a discussion with Mehrdad Mokhtari, Senior Earthing Systems Engineer at Enspec, on the role of Earthing Studies within grid-connected project design.
Earthing studies form a fundamental part of the safe design and operation of grid-connected electrical infrastructure. They underpin personnel safety and support reliable system performance. They are also a prerequisite for regulatory approval across transmission and distribution networks.
At Enspec, Earthing is treated as a core engineering discipline. Our approach focuses on delivering studies that meet safety requirements, integrate with wider power system analysis, and align with network operator expectations from the outset of a project.
Earthing as a prerequisite for energisation and operation
For grid-connected projects, earthing and safety studies must be completed and accepted before substations can be energised and operations can begin. Without these studies, grid connection cannot be authorised.
As connection voltages increase and site layouts become more complex, earthing design plays a central role. It supports fault current management, voltage gradient control, and safe access for operational personnel. Deficiencies at this stage can delay approval, commissioning, and energisation, directly affecting project programmes.
Experience across renewable and storage projects
In addition, Enspec delivers earthing studies across a wide range of grid-connected developments, including:
- Wind farms
- Solar farms
- Battery energy storage systems
These projects span voltage levels from 11 kV up to 400 kV. They also cover multiple stages of development, from early design through to final approval. Each study is developed to reflect site-specific soil conditions, fault levels, and network interfaces, ensuring alignment with both safety requirements and network operator standards.
This breadth of experience supports consistent delivery across different project types and connection arrangements.
Common challenges identified at project entry
In practice, delays associated with earthing studies are often linked to gaps earlier in the project lifecycle rather than the technical analysis itself.
Common issues include:
- Absence of approved initial earthing layout drawings
- Incomplete or delayed data from network operators
- Unclear understanding of documentation requirements
- Late engagement with earthing specialists
To address this, Enspec provides an Early Requirements Document at the initial stage of each project. This clarifies required inputs, aligns expectations with network operators, and supports efficient progression through analysis, reporting, and approval.
A dual-focus approach to earthing studies
As part of this approach, earthing systems are assessed from two complementary perspectives.
Personnel safety
Ensuring protection against system faults through the management of touch and step voltages and the provision of safe conditions for operational staff.
System stability and equipment protection
Supporting reliable system operation through effective fault current management and integration with wider power system studies.
This dual-focus approach ensures earthing studies contribute to both safety and long-term system resilience.
Supporting safe and compliant power systems
A poorly designed Earthing System can result in safety risks, equipment failure, and extended outages where repair or replacement is complex and costly. Robust earthing studies provide confidence that electrical infrastructure can be energised safely, operate reliably, and remain compliant throughout its operational life.
Through experience across renewable and storage projects, and close alignment with network operator requirements, Enspec delivers earthing studies that support safe, resilient, and compliant grid-connected systems.
Learn more about our Earthing Studies services
If you would like to learn more about how Enspec delivers earthing studies for grid-connected projects, you can explore our Earthing Studies services
