Is A Neighbour’s Home Battery Keeping Your Lights On?

Home batteries are often promoted as a way to keep the lights on when the grid goes down.

But according to a new report from the Australian Energy Market Operator (AEMO), they may increasingly be helping keep the grid up in the first place.WA’s latest Electricity Statement of Opportunities (ESOO) shows the state’s electricity outlook has improved significantly compared with a year ago. New generation projects, large-scale batteries and other investments are all strengthening the forecast.

Among them are growing numbers of household batteries that AEMO expects will work together to reduce pressure on the grid during periods of high demand.

Why Has WA’s Outlook Improved?

AEMO isn’t a think tank or lobby group. It’s the organisation responsible for operating Australia’s major electricity markets and planning for future electricity supply.

Each year it publishes an Electricity Statement of Opportunities, which assesses whether enough generation capacity is expected to be available to meet future demand.

Last year’s report painted a relatively tight picture for the years ahead. This year’s report is considerably more optimistic.

AEMO says the forecast supply outlook has improved substantially, with existing and committed projects now expected to provide a comfortable surplus of capacity through the period where shortfalls had previously been anticipated.

The improvement comes from a combination of factors, including new generation projects, large-scale batteries and updated assumptions about future supply.

What Role Are Home Batteries Expected To Play?

One of the more interesting details in the report is that AEMO is also counting on household batteries to help support the grid.

The ESOO forecasts coordinated home batteries reducing annual peak demand by around 200 MW in 2028-29. To put that into perspective, that’s roughly equivalent to a small power station’s worth of demand reduction occurring when the grid needs it most.

The modelling assumes hundreds of megawatts of distributed battery capacity will be available through virtual power plants (VPPs) and other coordinated programs.

In simple terms, batteries sitting in garages across WA can be charged and discharged in a way that helps reduce strain on the grid during periods of high demand.

Individually, a home battery may not seem particularly significant. Collectively, thousands of them can begin to make a meaningful difference.

The Irony Of Backup Power

SolarQuotes founder Finn Peacock’s home battery meant his place was the only house on the street with the lights on during a blackout, but batteries are becoming so plentiful blackouts are set to be prevented in the first place.

There’s an interesting irony here.

Many people like the idea of a battery because it can provide backup power during a blackout.

Yet as battery numbers grow and coordination improves, those same systems may increasingly help reduce the likelihood of blackouts occurring at all.

The battery sitting in your garage won’t keep the electricity system running on its own.

But according to AEMO’s latest planning assumptions, thousands of batteries working together could become an increasingly important part of how the broader grid stays reliable.

For more on batteries and blackouts, read about the different levels of blackout protection batteries offer to a home.