The Tesla big battery at Hornsdale in South Australia continues to make its market on the Australian energy market, pocketing another $4 million in the fourth quarter from the provision of frequency and ancillary services.

The number was revealed in the Australian Energy Market Operator’s latest Quarterly Dynamics Report, which also reveals a growing focus on energy storage, and time shifting and energy arbitrate in particular.

The fourth quarter was notable because it saw the number of big batteries on the main grid multiply, with the addition of the Dalrymple North battery in South Australia, and the Gannawarra and Ballarat big batteries in Victoria.

It also saw a record amount of pumped hydro used since 2008, a sure sign of the greater role for energy storage that is to come as the share of wind and solar continues to soar, and more battery and pumped hydro systems, along with other forms of storage such as hydrogen and solar thermal, come into the system.

The performance and business model of the Tesla big battery has been a source of fascination for the industry since its opening more than 14 months ago. Tesla founder and CEO Elon Musk recently confirmed that the $95 million facility was likely to pay itself back within a few years.

The battery, actually owned and operated by Neoen Australia, receives a $4 million a year payment for providing grid services to the South Australia government – a payment worth significantly more given its recent performance keeping the lights on in the state after a lightning strike in northern NSW led to load shedding and generator trips in all other states.

Tesla has also made money out of the FCAS market, and lowered costs at the same time. Its presence has effectively destroyed a “cartel” like play that pushed prices into the stratosphere, and allowed AEMO to remove constraints that were exploited by the gas generators.

The latest data from AEMO are of particular interest. It shows that the Tesla big battery’s revenues from FCAS continued apace, and it gained $4.5 million (net) from FCAS contingency and regulation markets ($4.9 million revenue minus $0.4 million in costs). (A small amount of that might have been attributable to other batteries).

Demand response, through specialist aggregator EnerNoc, also captured a $3.5 million share of those two markets. Between them, batteries and demand response had captured 27 per cent of that market.

But it also reveals growing opportunities in energy storage and time shifting, likely to be the key metric for most of the batteries that follow, given the opportunities within the FCAS market are limited.