A Victorian trial is taking a different approach to managing demand during peak events, writes Steven Neave of Electricity Networks.
When smart meters began rolling out to every Victorian home almost a decade ago, it was contentious. Questions were asked about why we needed them and what benefits would they bring.
But it was the Victorian Government’s foresight that paved the way for an initiative that contributed to demand response trials this summer, delivering tangible benefits for customers.
During the past six months specialist teams at CitiPower, Powercor and United Energy have been devising and testing a demand response initiative that is pushing innovation boundaries. We’ve called it a Smart Meter Voltage Management (SMVM) system and it involves lowering voltages quickly across the network and at scale to reduce the pressure on networks when high temperatures and subsequent use of air-conditioning causes electricity demand to rise significantly.
While this process has been used in the past to help ease demand on the network, smart meters are allowing us the ability to drop voltage lower than we have been able to previously by monitoring voltage on the low voltage network.
By using this technology we can ease pressure on the grid while ensuring the reliability of supply and keeping customers within acceptable voltage levels. We believe we are the first networks that are leveraging investment in smart meter capability to deliver voltage reduction at this scale globally.
And, best of all, customers don’t need to take any action. In fact, customers are unlikely to be aware the initiative has been deployed.
Demand response initiatives aren’t new. Networks have been delivering demand response programs for many years to deal with local network constraints. In many cases these programs will involve asking customers to reduce consumption at peak times in exchange for payments. Others involve the use of batteries or generators.
All play an important role in reducing the need for building expensive infrastructure to cope with a handful of peak demand days and this means less cost to customers.
With the closure of the 1.6GW Hazelwood Power station in Victoria early last year, a range of demand response initiatives are being implemented or trialled this summer.
While other demand response initiatives call on customers to take action, such as curbing power use in exchange for payment, what makes this program unique is that customers won’t have to do anything. The work will all be done behind the scenes, with controllers managing peak demand without impacting on customers.
For sensitive load and critical needs customers, such as life support customers, smart meters allow us to individually monitor their voltage levels to ensure they remain in an acceptable and safe limit.
The process
Typically, the Australian Energy Market Operator (AEMO) will provide our networks 24 hours’ notice about a predicted high-demand event. On the day of the event we will get an hour’s notice to achieve our predetermined demand-reduction targets, committed to under AEMO’s Reliability and Emergency Reserve Trader (RERT) scheme.
In the case of United Energy, which is one of five pilot projects trialling demand response on peak demand days in Victoria as part of a three-year initiative funded by the Australian Renewable Energy Agency in partnership with AEMO, it may receive just 10 minutes’ notice to achieve this reduction.
As part of this emergency backup initiative, CitiPower and Powercor expect to contribute 110MW of capacity. That’s enough power to the grid to supply about 110,000 homes. United Energy will contribute at least 12MW.
Once an event has been called, our controllers will move quickly to incrementally drop voltages network-wide. This will be achieved by lowering voltages at almost 150 zone substations across our three networks, with controllers moving customer voltages from the upper half of the acceptable voltage range to the lower half.
A set of traffic lights and visualisation tools will show when volt limits have been reached using information from our fleet of smart meters. A green light indicates to the controller to lower the volts, orange means no change and a red light means raise the volts. This process will continue until the agreed target is reached and all traffic lights are orange.
Fresh data is provided every five minutes to provide an accurate appraisal of supply reliability. This process will be automated progressively over time using network data analytic systems.
The closure of older power stations is opening the door to newer and smarter technology. While there are always events that we can’t control that may impact supply, with these advances in technology we’re innovating on a global level to manage demand on Victoria’s power grid quickly and cost-effectively.