Across Australia, and particularly in NSW, the uptake of rooftop solar has soared, with more than 450,000 premises across the state having solar panel installations, providing 5GW of generation power. From an environmental position this is encouraging to see, however, an increase in uptake brings emerging challenges. One such challenge for electricity networks is maintaining voltage within 216- 253V, which can become difficult with an increase of solar PV installations.
There are typically three strategies networks can implement to manage voltage on the low voltage network:
- Limit the connection of solar panels
- Augment the network, which can include replacing powerlines or upgrading transformers
- Trial innovative behind-the-meter methods for voltage management
Australia’s largest distribution network business, Essential Energy, chose the innovation road and participated in the Networks Renewed project to trial a voltage management system using smart technology to incentivise customer inverters.
The Institute for Sustainable Futures at University Technology Sydney partnered with Essential Energy, the Australian PV Institute and two electricity network businesses in Victoria – AusNet Services and United Energy– with the project receiving funding from ARENA as part of its Advancing Renewables Program. The project commenced in September 2016 and was completed in April 2019.
The project was delivered in two separate stages:
- Pilot stage: a limited number of customers to assess the effectiveness of the project plan, with an overarching objective of achieving a measurable network benefit from customer systems
- Market stage: lessons learnt from the pilot stage guided the design of the market stage, and the number of eligible customers during the market stage was significantly increased with the aim of addressing an emerging network constraint
Essential Energy’s Executive Manager Engineering, David Salisbury, said, “We’re committed to delivering a network that is responsive to the changing needs of our customers.
“The Networks Renewed project showed that we can provide voltage management services to the network by augmenting our network intelligence, bringing groups of people together to use and share solar power, and using new technology to manage voltage variations using customer batteries.”
The trial was successful in proving viability and customer benefits, including:
- Voltage management at a lower cost compared to other options
- Enabling the network to take up higher levels of rooftop solar with minimal impact on customers
Customer engagement key to the trial’s success
Essential Energy worked with Reposit Power to provide the voltage management service for its customers. Organisations like Reposit Power (and Mondo which was the technology partner for the Victorian trial) provide an aggregation of customer batteries into the market, and in return provide revenue to customers which they could not access previously.
For the trial, Essential Energy created a Distribution Level Market (DLM) to enable voltage management services. During evening peak periods, when networks are generally under stress from customer load, Essential Energy invited bids from customers to supply voltage management at a price of $1 per kWh.
The price signal acted as an incentive for Reposit Power’s smart control electronics to respond on the customer’s behalf. Customers were at the centre of the approach during this trial, and the smart controller technology would only bid when it was in the customer’s interest.
Additionally, the project emphasised customer choice –customers were able to choose when and to what degree they participated in the market.
Extensive engagement was undertaken during the project to support this customer-centric approach, with Essential Energy ensuring customers were fully informed through each stage of the demonstration, and that they would not be worse off as a result.
In addition to direct engagement, a number of face-to-face forums were held during the project.
“We found that customers appreciated being able to engage with our team while working through this new process,” Mr Salisbury said.
The project was a success for customers and for the electricity network, demonstrating that participating customers were still able to gain a financial benefit by providing voltage management services to the network at times of peak demand.
“Through the project, we sought to drive lower-cost solutions to address network voltage constraints, support the uptake of customer solar PV, while maximising value to customers,” Mr Salisbury said.
“We also found that customers who participated had their bills reduced by Reposit Power’s intelligent algorithms which worked to optimise energy management in their homes.”
In addition to the above, across the trial area, there was sufficient improvement in network voltage that a network upgrade has likely been avoided.
This solution has come at a lower cost compared with the traditional solution of a physical network upgrade that would be required to address the emerging voltage constraint. All customers will benefit from this saving in the form of lower power prices across the network.
The increasing rates of solar uptake across Australia are presenting challenges for both customers and electricity networks. Existing options to manage voltage and power quality can be costly, leading to higher power prices for customers.
Through the Networks Renewed project, Essential Energy helped achieve an Australian first by demonstrating that with sufficient technology, customer’s batteries can help to provide voltage management services to the network.,
The innovative nature of the project has been recognised by other industry associations.
“I’m thrilled that Essential Energy is a finalist in Engineers Australia’s 2020 Engineering Excellence Awards – Newcastle Division,” Mr Salisbury said.
“It’s fantastic recognition of the hard work of all involved to make this project a success for the benefit of our customers.”