We want to inform you about Powercor’s new earthing assessment requirements and how they might affect your projects and schedules.

Background

To ensure compliance with national standards, public safety, and network reliability, Powercor now requires developers and their contractors to conduct and implement earthing assessments for all contestable projects that include one or more new HV earths. This requirement will be at the developer’s cost and applies to projects with as-built plan submissions (PCA41) received from 1st July 2024 onwards, and detailed designs received from 1st January 2025.

In the past, insufficient earthing assessments led to significant issues, including safety hazards, equipment damage, compliance failures, and operational disruptions.

The changes to earthing assessments will ensure compliance with DG041 and AS/NZS 4853. This means that all contestable project designs will meet Australian standards for Earth Potential Rise and Low Frequency Induction, which have been in effect for several years.

Actions Taken by BFD

To effectively handle the earthing assessment process, Blue Frog Design has taken several proactive steps.
Our team has undergone extensive training with qualified earthing engineers.
We have acquired state-of-the-art software for precise and reliable earthing simulations and designs.
We have invested in high-quality equipment for soil resistivity testing and other necessary assessments.

These measures enable us to deliver thorough and compliant earthing solutions tailored to the specific needs of each project.

Earthing Assessment process

Below is an outline of the new process.

1. Data Collection from Powercor

To conduct the earthing assessment, we require network data from Powercor, such as fault levels and clearing times. The following steps will be taken to acquire this data:

• Lodging Request – Developers and their contractors can request fault levels and clearing times through Powercor’s network data request web form. For new projects (from 15/07/2024), this request will be initiated via the updated ‘Contestable Works Agreement’.
• Authority Letter – Powercor requires an authority letter from the developer if consultants manage the data collection process on their behalf.
• Data Share Agreement – Powercor will issue a data share agreement contract for both the developer and the consultant. Both parties need to sign and return the contract to Powercor.
• Invoice and Data Release: Once the contracts are executed, Powercor will raise an invoice within 24-48 hours. Upon payment, Powercor will release the information in approximately 4 weeks.

2. Soil Resistivity Testing

We will conduct a comprehensive site survey and collect soil resistivity measurements, along with information on existing earthing arrangements. This data forms the foundation for our design process.Powercor’s process requires a staged approach to ensure compliance.

If the first stage results in a compliant design, no further work is needed. If not, we will proceed to the next stage, which may involve additional costs.

The three-stage approach is as follows:

Stage 1 – Desktop Analysis

• BFD will complete an initial earthing assessment using standard earthing arrangements and approved software.
• We will provide a brief report detailing the outcomes, indicating whether the design is compliant.

Stage 2 – Detailed Desktop Design
This involves a more detailed assessment using multiple software tools.

• The model will consider non-standard designs and options for tying in adjacent and nearby assets.
• Liaison with CitiPower & Powercor may be required for non-standard earthing arrangements.

Stage 3 – Full Detailed Earthing Design

• Triggered if stages 1 and 2 do not result in a compliant design.
• May include site inspection, further soil resistivity testing, current injection testing, and design of multiple options.
• The output will be a compliant earthing design with supporting documentation.

We understand these new requirements may affect your projects, and we are committed to supporting you through this transition. In the short term, there will be additional costs that will be communicated to you via a variation. If you have any questions or need further clarification, please do not hesitate to contact us.