AusNet: We've been overwhelmed by the solar rush, and we’ve made mistakes

The growth of rooftop solar and battery systems is one of the most exciting aspects of the transition we are seeing to our energy system.
As a network operator, AusNet Services sees enormous potential for this growth to deliver real improvements in network reliability and affordability for our customers.
This is why we have welcomed the Victorian government’s Solar Homes policy as a means to ensure Victoria keeps pace with states such as Queensland and NSW in the roll out of these new technologies.
We are currently working very closely with the Victorian government to maximise the benefits of the policy for customers and ensure that as many people as possible can take advantage of it.
The early impact of the Solar Homes policy has been significant. We are seeing a very large up-tick in solar connection applications this year.
In the first two months of 2019, AusNet Services had more than twice the number of applications for solar connections from the equivalent months in 2018. We expect solar connections to more than double from 2018 to 2019. That’s great.
Our role in this as an electricity distributor is clear. We need a quick and easy process for our customers to connect solar and batteries to the network. And we also need to do the necessary work to the network so that it keeps pace with the change in usage that solar and batteries bring.
AusNet Services recently launched its new online tool to process applications for solar and battery connections. The previous process took far too long and was far too bureaucratic.
Our new online tool means that customers and solar installers can, in over 90 per cent of cases, get approval for a solar connection immediately.
Manual technical assessments are still necessary for about 10 per cent of cases. We are working hard to bring the assessment time down. No new process is ever perfect and so we are working with installers to get their feedback and address these issues as soon as possible.
Making sure that the network can cope with demand for batteries and solar is more complicated. Most of AusNet Services’ residential network was built to supply 2kW per house where the typical size of new solar systems is closer to 5kW (and many systems are significantly larger).
At modest levels of solar take-up, there is no problem at all. But in a simple example, when a network built to supply 2kW per house has more than 40 per cent of houses exporting 5kW, then we start to encounter capacity problems.
If we allowed everyone to connect any size system, we would overload those local lines and have widespread overvoltage in these networks, impacting reliability and safety, and on occasion preventing inverters from exporting.
What this means for residential customers right now is that we only allow a maximum of 10 kW inverter capacity (i.e. the size of the total system) and 5 kW export limit per phase. This is a crude way of sharing capacity – so that more customers can install systems.
We hate having to do that and so we’re not sitting on our hands. We’ve already performed a large program on existing transformers to help manage high voltages in some areas. This helps but is not a long term solution.
We believe that part of the solution is to invest in upgrading our network infrastructure so it can meet this demand.
In our recently released draft pricing submission to the Australian Energy Regulator, we have forecast to spend $5.5 million in technology investment and $20 million in network investment to ensure that more people can connect solar and battery systems.
You might think that’s too much, or even too little – we’d love to hear from you as part of our current pricing review consultation via this link.
Another part of the solution is the development of community scale energy projects like the ones we are trialling currently in Yackandandah and Mooroolbark.
These community scale projects can allow people to connect even where there are existing constraints on their local network.
Technically, we use smart technology to share capacity dynamically. More importantly, we are part of a community conversation on how to work through this transition to meet our customer and community needs.
We’re excited about how electricity networks can help customers to play a greater role in how their energy is produced and used. And we are working hard to make it happen.
Alistair Parker is executive general manager of regulated energy services at AusNet Services