Electricity Asset Management Plan 2019-2029
83
Vector Limited://
4.1.9 OUR POWER QUALITY STRATEGY Vector provides a nominal voltage of 230 V ±6% for single-phase power and 400 V ±6% for three-phase power at the point of supply, as required under the Electricity (Safety) Regulations 2010. Maintaining the network so it operates within the permissible range is proving increasingly challenging. Local distributed generation (for example, solar PV) is pushing the network voltage beyond the upper levels, while winter demand is testing the lower threshold. Access to customer smart-metering data would offer real benefits, allowing for improved identification and response to identification of voltage issues. Currently, and pending access to this data, we are reactive. When we are notified of instances of the network operating outside the regulated voltage range, we investigate and then remedy the problem. Vector has installed PQMs (power quality meters) at a number of its zone substations, to primarily baseline and trend harmonic 6 levels on the network. Variable speed drives tend to create harmonics and while they have been used by industry for a long time, we are interested in monitoring and understanding the impact of power electronics operating at the residential level, particularly inverters associated with solar PV and electric vehicle and battery charging. Increasingly, we are being approached by our commercial and industrial customers who have experienced production outages that may have been caused by network disturbances. These disturbances may be caused by depressed voltage whose source is network faults on adjacent circuits, or even by Transpower switching issues. Nevertheless, loss of production and extra costs to the customer are the result. The data from PQMs is analysed to determine the cause of any network disturbances, and changes made to improve our performance to meet regulatory requirements. There are, of course, instances where PQM issues are caused by disturbances in the customer’s own electrical installation, in which case we recommend the customer investigates, tests and then takes steps to improve the electrical installation. 4.1.10 OUR CLIMATE CHANGE AND SUSTAINABILITY STRATEGY A key focus area of our sustainability approach is community resilience. The strategies to address this are already covered in the previous sections on Reliability and Resilience Strategy, and Vegetation Management Strategy. In addition, when designing, building and operating the various components of the network, sustainability will be a key consideration. Under Vector’s sustainability strategy, we are in the process of adopting the framework developed by the Infrastructure Sustainability Council of Australia noted in Section 3.11 to deliver sustainability outcomes through the asset management lifecycle. Circular economy approach to materials Along with reducing carbon emissions, we are taking a broader view of materials entering the network, applying the principle of kaitiakitanga (stewardship) to ensure the maximum recovery of materials at end of life. This is a natural progression on from normal practices such as resource efficiency, where we aim to reduce our consumption of resources in the management of the network, generating revenue through the sale of surplus materials, and reducing waste that goes to landfill. Taking a circular economy approach calls for a different approach to procurement and technical specifications. We have begun and will continue to work with both suppliers and internal teams to pilot the use of new materials and end-of-life approaches, and new service models. Network components such as transformers, cabling and switchgear contain high percentages of relatively easily recoverable materials which are processed by scrap metal companies. Hardwood poles generally have a second life while concrete poles can be crushed with recovery of any steel reinforcing.
Other items like oil used in transformers is recovered and reused in applications in other sectors where a lower quality product is acceptable.
With increased battery energy storage systems on the network Vector is collaborating with other key players in the value chain for batteries to explore alternative options for end of life disposal. In the near future, we expect our network batteries
―
6 Harmonics occur on the network when current and voltage are distorted and deviate from sinusoidal waveforms. Harmonic currents are caused by non-linear loads connected to the distribution system
Made with FlippingBook - professional solution for displaying marketing and sales documents online