How a virtual ‘big battery’ could get South Australia’s grid out of hot water

One Step Off The Grid

South Australia’s 200,0000-odd residential electric hot water systems could be transformed into a massive virtual battery to store the state’s cheap and abundant solar during the day and help solve grid stability problems.

Under a proposal put to the South Australian government by NSW-based firm Intellihub, residential smart meters would be used to dynamically control hot water systems, turning them into a sort-of solar sponge at times of minimum demand – often when solar generation is highest.

This would offer benefits for consumers, including saving them money on energy costs, while also taking pressure off the grid by providing enough combined demand at the right times and locations to help maintain the stability of supply.

Intellihub says the creation of a hot water virtual power plant could also provide a new platform for retailers to develop innovative consumer-friendly products, offering improved services and better control over energy costs.

The proposal comes as both the South Australia government and the Australian Energy Market Operator scramble to find ways to better accommodate the state’s world-leading distributed solar uptake, and avoid the need to take measures such as switch off large amounts of rooftop PV.

That sort of “last resort mechanism” was flagged by AEMO in its Minimum Operational Demand Thresholds in South Australia Review, handed to the state government in May, and released publicly in June.

The report noted that zero operational demand – where rooftop solar reaches the point where it effectively eliminates grid demand – could occur within the next one to three years and, unless AEMO has new powers to manage rooftop solar, presents a real danger of a major blackout.

As RenewEconomy editor Giles Parkinson explained here, AEMO has long planned a “roadmap” to introduce new standards, new technology and protocols to manage this growing resource, but the looming “zero demand” benchmark has forced it and the state government to fast-track their response.

And while AEMO has some near-term tricks and band-aid solutions up its sleeve, the South Australian government is doing its bit to find remedies through a Smarter Homes consultation on minimum demand solutions – the prompt to Intellihub’s proposal.

“Our proposal supports the use of energy rather than the loss of energy to help maintain grid security across South Australia,” said Intellihub CEO Adrian Clark in a statement on Monday.

“With intelligent scheduling and staggering enabled by smart meters, these systems can deliver a continuous aggregate demand of 200-300MW to help maintain grid stability when solar generation is highest.

“It works exactly the same way as a battery, soaking up energy when required, and releasing it when it’s needed. It creates value for consumers and the energy market, rather than eroding value.”

To read the full story on RenewEconomy sister site One Step Off The Grid, click here…