Innovative Technology Work
We have several committed initiatives to help lift grid performance over the next five years. They are:
- introduce variable line ratings across New Zealand, and dynamic line ratings for specific lines
- continue with our strategic replacement programme for major plant
extend monitoring on key or at-risk assets - introduce real-time asset management in grid operation
- install area wide Reactive Power Controllers in main centres
- install static compensators (STATCOMS) in Auckland
Line Ratings Project
What we're doing
We are carrying out a project to change the way we determine ratings of our transmission lines. Currently, we set our line ratings (the capacity of each line) based on the season. The line ratings project aims to progressively improve the way in which we rate our lines, and where possible, unlock additional capacity from our existing transmission network.
This project supports our view outlined in Transmission Tomorrow to get more capacity out of our existing assets where possible.
This is a company-wide initiative, with both the Grid Owner and System Operator side of the business. The project is split into the following stages:
| Stage | Description | Timeline/Status |
|---|---|---|
| 1. Enhanced seasonal ratings | Implement a shoulder (spring / autumn) rating period. | Complete – implemented in March 2010 |
| 2. Line rating methodology review | Review and confirm the basic equations and parameters used to calculate line ratings. | Complete – the new methodology will be implemented at the same time as VLR. |
| 3. Variable line rating (VLR) trial | Implement VLR on six lines to develop our understanding of what is required for full VLR implementation (stage 4). | Complete - implemented November 2011. |
| 4. Variable line rating (VLR) implementation | Use historic weather data to more accurately calculate line ratings which will vary by line segment and throughout the year. | TBC following outcome of VLR trial |
| 5. Dynamic line rating (DLR) trial | Use real-time data to calculate line capacity on an asset of interest (for example, a wind generation connection) | TBC |
Why we're doing it
The purpose of the project is to unlock (where possible) additional capacity from our existing transmission network. The benefits of this include:
- Deferred and/or reduced capital expenditure
- Increased competition in the electricity market and efficiency of generation resources
- Greater ability to get maintenance and development work done
- Ensure compliance with legislative clearance requirements
- Lead by example in innovative techniques and solutions.
Want to know more? Have a look at presentation below to get a better insight into this technological and innovative strategy.
Want to know more?
Visit the System Operator website to learn more about Interim Variable Line Ratings.
Additional information can found in the resources below
| Resource | Description |
|---|---|
|
This presentation provides an insight into this technological and innovative strategy. |
| Commentary on the line rating methodology. |
For further information contact the grid investment projects team.