A project by Luceo Energy that shows the effect of solar exports on the grid is expected to help the network owner target investment in capacity.
Rooftop solar has brought joy to the 2.6-or-so million who have paid for PV systems and anguish to the community of engineers who look after the grid those homes are connected to.
As the sun beats down on household systems sized far larger than midday load requires, electricity generated by PV panels is exported to networks that may be inadequately designed to take it.
Some say it’s a big problem. The truth is it’s a big opportunity to study how distribution networks could be adapted to manage high levels of solar penetration and exports – and handle more. Combined with tariffs that encourage daytime load, the “problem” of solar exports might disappear.
That’s the theory, at least. In reality, many distribution networks around the country have a long way to go. The problem is that they cannot see what’s happening along their wires. The doctor knows something’s not right, but it’s as if the X-ray machine hasn’t been invented yet.
Finger on the pulse
A trial in Queensland has filled in some blanks. The first stage saw 20,000 sensors developed by Luceo Energy installed at connection points on the Energy Queensland network, to measure voltage and current. Twelve months worth of data have been collected by the army of sensors, with measurements arriving at the company’s cloud platform every minute. The sensors have been distributed on the network between Cairns in the far north and down to Coolangatta, across urban and rural centres on the Queensland coast, all in front of the meter.
As solar exports continue to flow off rooftops and cause hotspots of instability within distribution networks, the owners of those poles and wires can be frustrated by how difficult it is to see exactly what’s going on. A river of data from the Luceo sensors puts Energy Queensland’s operations in clear view. So, what is the network learning about itself?
“Quite a lot,” says Luceo Energy CEO Patrick Matweew. “With real-time data they can see changes as they are happening; they can see the network breathe in quite a small resolution.”
As expected, constraints can be viewed throughout the day as solar exports or other operations affect the power quality along the wires. “You can now pinpoint between, say, two houses whether a line is down or an incident happened,” Matweew (pronounced Mat-vay-uss) tells EcoGeneration. “From an operational and safety perspective the operators are now much closer to understanding what’s happening in real time.”
An example is the ability to sense risk to broken neutral integrity and schedule maintenance before failure, he says.
“It gives you a lot of opportunity for pro-active maintenance and risk-avoidance. We can read if the connection is in a healthy state or is deteriorating; we can tell you if there are connections in your network that need fixing very soon because they are getting to a state where they could potentially break.”
You can’t argue with that
A picture of network health is relayed a bit like a collection of pins on Google Maps, where users can zoom in and out, clicking on locations to view details. Alerts and notifications lead users directly to sites where further investigation may be warranted. “Once you go deeper you will see all the charts and graphs [presented by cloud-based analytics] for that site.”
Other than working to keep voltage from straying outside the desired bandwidth the network is keen to ensure the three phases are correlated and, fundamentally, that its map of its poles and wires agrees with what the Luceo sensors are picking up. “Maps may have been updated, but not always correctly, and now we can verify [them], which has implications on their investment and maintenance.”
That’s a clear picture of what’s happening in front of the meter, but any network where rooftop PV is popular will also want to know what’s happening on the other side – among the growing multitude of inverters linked to solar systems and residential batteries. The Luceo device will pick up solar exports post self-consumption, allowing a network far deeper knowledge of which households host PV systems. “But we can’t see what’s happening behind the meter because we are not entitled to know that,” says Matweew, also the CEO of smart energy storage and software company Redback Technologies.
It is technically possible, however, to include data from distributed energy resources such as household PV and storage on the platform and “complete the picture”. This is the subject of another project for Luceo, where with the help of $2.6 million in funding from the Australian Renewable Energy Agency it is trying to access behind-the-meter data – or “find the missing piece” – and assemble complete live replicas of energy systems.
The $5.7 million Project Shield (for Synchronising Heterogeneous Information to Evaluate Limits for DNSPs) also includes Energy Queensland, along with Essential Energy in NSW, the University of Queensland and Brisbane-based technology company GridCube. The consortium is aiming to find how data from DER can be interpreted so that networks can determine hosting capacity for rooftop solar. The ideal outcome would be that networks will have a tool that may allow them to accommodate more solar without any need for upgrades, or to make far more refined decisions about such upgrades. “Or, now [a network] will have a good business case to say, ‘I’ll build a bigger transfomer,’” he says. “We’re trying to find a data-driven approach for smarter investment for networks.”
Start of something big
That’s two projects, but Luceo and Redback have many other irons in the fire.
“At the moment the industry is crazy; the network and renewables integration is a massive piece,” he says. “As a technology provider we are trying to team up with as many people as we can to showcase what’s possible.”
Word has got around about the Energy Queensland trial and Matweew admits Luceo is talking to other networks.
The home solar market is growing fast, but as consumers work out that the grid won’t always be able to take too much of a good thing – their unused midday exports – and pay handsome returns they might start to feel resentment. It would be a short-sighted response, as the issue of high exports causing issues in the grid was predicted many years ago. Things can change quickly, however, and the industry is anticipating a big shift to more dynamic, agile operations. If all goes well, energy users and suppliers will both benefit.
“One of the reasons consumers love solar is it makes them more independent and less vulnerable to what they see is an energy market that hasn’t worked in their favour in the past,” Matweew says. “If we reinstate trust in the system, as consumers we then don’t have this emotional reaction to anything limiting solar export.”
From Matweew’s vantage, technology can fill the task of trusted powerbroker between user and supplier – and dilute the effects of “what are often not fact-based responses”. As for understanding the appeal of expensive home energy systems, it’s no surprise he advocates for self-consumption as a more important investment trigger for consumers than revenue from exports.
Tomorrow’s DER-owning energy user might have a relationship with a demand response aggregator or be taking part in a virtual power plant. There will be many more avenues to sourcing electricity. “It has to do less with technology and more to do with education and reform of regulation that allows these things to emerge. From a technology perspective we are more of less there.
“It’s about getting everybody on board. The future will be different, but it might be significantly better for everybody.”