Alice Springs tests potential for remote control of home solar and batteries

A renewable energy microgrid set up at the Northern Territory’s Charles Darwin University will test the ability of home solar and battery inverters to provide “essential support services” to the Alice Springs grid as it shifts to 50 per cent renewables by 2030.

The testing at CDU’s Renewable Energy Microgrid Hub for Applied Research and Training (REMHART) in Darwin is being conducted in partnership with the Alice Springs Future Grid, a collaborative effort to iden­ti­fy and over­come bar­ri­ers to high renewables grids.

CDU says the primary technology being tested is three residential inverters – increasingly “intelligent” and programmable devices that convert energy generated from solar panels and batteries into electricity suitable for use in the grid.

The study will test the ability of the inverters to respond to changes in network frequency and to provide a reliable response, which could be used in the future to prevent power cuts or other interruptions to electricity supply.

The NT, which is not part of Australia’s National Electricity Market, has three regulated networks, including the southern electrical grid, which services the Alice Springs area which is home to about 28,000 people.

Small though it is, the Alice Springs grid boasts some of the highest rooftop solar penetration in Australia, and harnessing this resource will be fundamental to its journey to 50% renewables by 2030 – a target the NT government committed to in 2017, for the entire Territory’s electricity supply.

So far, apart from an enviable rooftop solar resource and a number of larger-scale rooftop and ground mounted arrays, not a great deal has been achieved on the road to 50% renewables.

In Alice, a smallish grid-scale battery (5MW/2.5MWh) was switched on back in 2018 to help manage the rooftop solar load, particularly during cloud cover, and to improve power system stability by helping to smooth PV output.

But as South Australia has learned, gaining more fine-tuned control and visibility of rooftop solar generation and/or battery storage systems via the source – the inverters – is a far more useful tool.

CDU’s Energy and Resources Institute director Professor Suresh Thennadil said the so-called REMHART microgrid, which the university inherited from Hitachi, has been adapted for exactly such purposes.

And he says the beauty of the facility is that researchers don’t have to wait for things to happen on the grid, but can enforce certain conditions and run all sorts of scenarios and see how the inverters respond in a safe testing environment.

“In the coming years, not decades, we will need a revolution in power generation and distribution that has not been seen since the initial rollout of a national power grid,” Professor Thennadil said.

“The testing facility is a vital tool in making this power revolution happen in the NT, with research and testing of new renewable systems, and training provided to build industry capacity.”

CDU says that the three individual solar, hybrid and battery inverters – chosen for their current popularity as frequently installed brands – have been installed and will be tested for response characteristics including delay time, ramp time and maximum charge/discharge power outputs under different load and generation scenarios.

The University says that findings from the research project will assist in measuring how residential inverters can provide services to the grid.

The Alice Springs Future Grid project is coordinated by the Intyalheme Centre for Future Energy on behalf of Desert Knowledge Australia (DKA) and backed by the Australian Renewable Energy Agency (ARENA) and the Northern Territory government.

Findings from the various research activities of Future Grid, including the testing carried out by CDU, will be considered for inclusion in the Alice Springs Roadmap to 2030 report, which is anticipated for publication until 2023.