FAQs

Solar Connect was a townwide solar and battery trial linking households via a Virtual Power Plant (VPP). House­holds in the VPP shared solar and battery power in ways that benefited the Alice Springs grid and informed the opportunities for the next generation of more sustainable energy solutions.

A Vir­tu­al Pow­er Plant (VPP) is typ­i­cal­ly a col­lec­tion of solar and bat­tery stor­age sys­tems that work togeth­er to allow coordinated control of their energy.

VPPs use smart technology to control the energy flow to and from the grid on demand – benefitting the household, grid and the community.

The trial became operational in October 2022 and ended in October 2023.

Alice Springs Future Grid created the Northern Territory’s first residential Virtual Power Plant (VPP). The trial looked at how a VPP can help keep the grid stable while increasing the amount of clean energy in the Alice Springs power system.

The VPP was part of a suite of innovative trials, models and investigations that looked at how to keep the Alice Springs network within voltage limits, reduce the reliance on gas power generation, and help the Northern Territory to reach 50% renewable energy by 2030.

In partnership with Territory Housing, the Alice Springs Future Grid installed 15 solar battery systems on public housing to ascertain the impact of public housing energy consumption behaviour into the Energy Grid.

It was recognised that solar has the effect of enabling those with the financial means to do so to reduce their power bills, while this project allowed these benefits to be shared with tenants. In addition, the Arid Lands Environment Centre led a Low-Socioeconomic study that presents baseline information on the challenges facing this section of the community in accessing direct benefits from renewable energy.

This is a subject of much discussion and study, and is even the focus of a current Australian Renewable Energy Agency (ARENA) funding opportunity. It does pose a looming waste management issue, with the design life of solar panels at 20 to 30 years, and many installed well over a decade ago. The International Renewable Energy Agency (IRENA) estimates there could be 60 to 78 million tons of photovoltaic panel waste accumulated globally by 2050. It also estimates the recyclable materials will be worth $15bn in recoverable value.

It is envisaged that recycling solar panels will create industry and employment opportunities, keep valuable resources out of landfill, help to retain rare elements, and prevent heavy metals leaching into the environment. There are a couple of companies working in this space in Australia.

Detailed studies have been conducted on this subject, concluding that dust does not have a significant impact on PV systems. This is perhaps surprising, but washing the panels with tap water in places where there is a high concentration of calcium (such as Alice Springs) can actually have a more negative effect than dust. The arrays at the DKA Solar Centre are washed once a year by a specialised company who use a reverse osmosis filtration system to treat their water before using it to wash the solar modules.

All reputable installers are registered with the Clean Energy Council. You can find out more in the Consumer section of its website.

Output will vary according to the weather, and you can monitor your inverter or read your meter to get an idea of your solar array’s performance. Most solar installers also allow remote monitoring through various apps. Another source of information will be your bill, and your solar installer will be able to assist with such enquiries.

The Battery Energy Storage System (BESS) in Alice Springs is designed to provide grid stability services. This is much needed, as the town has a high proportion of rooftop solar PV, which can create challenges in the grid during periods of high cloud coverage, requiring thermal generation to react as quickly as possible to pick up the slack. In these instances, the BESS can almost immediately support the grid while thermal generation ramps up or down. If it were to be used purely for storage, the battery would last about 40 minutes. Proportional to the size of the Alice Springs grid, it is the biggest battery in Australia. This perhaps illustrates why centralised battery storage alone isn’t a viable solution to support high renewable penetration in a town like Alice, just yet.

According to figures from Power and Water Corporation, Alice Springs had 2,018 grid-connected rooftop PV systems at the end of financial year 18/19. Rooftop PV was being installed at an average rate of approximately 200 systems per year. The “Roadmap to 2030” shows that more than 25% of the approximately 9,000 households in Alice Springs have installed DPV on their property rooftops.

Residential batteries can be fitted to most households with existing PV systems. Replacing the entire system will depend on the age of the infrastructure – panels and inverter primarily. Further information should be sought from accredited CEC installers, or alternatively see websites such as Solarquotes to gain a better understanding of the various technicalities.

With solar PV and batteries it is technically possible to go off-grid, but Alice Springs residents would need a very big battery or backup diesel generator to cover occasions where there is limited sun for consecutive days. The most common option is to install PV and BESS in proportion to household needs, and let the grid come to the rescue when its needed. In the future, plentiful PV and BESS will create a very resilient system, because it’s highly unlikely that they could all fail at once. For most people it is not financially viable to go off-grid, but as centralised energy generation incorporates a growing proportion of renewables, it means everyone will eventually be provided with cleaner energy.

It’s absolutely feasible before 2030 that we can work towards operation at 100% renewable energy at certain times of the day or year. This was a scenario modelled as part of the Roadmap to 2030. However, how frequently we do that and for how long will then become a question of economics and power system stability.

Solar is currently the only commercially viable renewable resource in Central Australia, and to reach 100% solar would require a very large (and prohibitively expensive) battery, to cover the overnight periods. Learning how to provide Essential System Services through renewable energy technologies is crucial to reaching 100% solar during the day. Future Grid's Wind Monitoring Study demonstrated that it may be possible diversify the Alice Springs energy portfolio. Although on its own it may be more expensive than the typical cost of wind generation in Australia, due to the poorer overall wind resources, it has a notable degree of solar/wind resource complementarity. That is the wind resource is most abundant in the late afternoon and evening when solar generation potential is significantly below maximum demand. Other factors that could assist - but are outside the scope of Alice Springs Future Grid - include the adoption of electric vehicles and their integration into the grid, and the development of a green hydrogen industry.

Knowledge sharing is a key focus for (funding agency) ARENA, and the Future Grid project has a prominent knowledge sharing plan, delivery of which is led by CSIRO. Reports generated through the project are hosted on the ARENA Project Page for Future Grid. It is recognised that lessons learnt in Alice Springs can be scaled-up and applied to other grids, such as the Darwin-Katherine Interconnected System (DKIS) and the National Electricity Market on Australia’s East Coast. The project’s main target audience is industry and government, so it is expected these entities will be the primary conduit through which lessons learnt in Alice Springs are applied elsewhere.

The Future Grid project (and the Roadmap to 2030) has significant value nationally because some of the research and findings demonstrated in the Roadmap, set out ways different parts of the power system will need to work together in the future. A key characteristic of Alice Springs is that it is small enough that the opportunity exists to test and validate interventions, but big enough that the results have direct applicability across a range of different systems and grids in Australia. To this end, Alice Springs is sometimes said to be “small enough to manage but big enough to matter”.

There have been other projects around Australia carrying out investigations in many similar areas to Future Grid. The difference is that Future Grid looked at a series of interventions in aggregate and how they could integrate as a system on a technical, economic, and regulatory basis. This is what made Future Grid fundamentally different; it brought public utilities together with leading industry experts, and local organisations. We collaborated in a way that was simply not possible in other locations. For comparison, if we look to WA; Horizon Power has demonstrated many of the technical interventions we were working towards, but they are doing it in the context of being a vertically integrated energy supply company, so its activities don’t require complex engagement with other entities. In other areas, such as South Australia, there are fundamental differences in the market structure, which provide economic signals that are not available in the NT. What Future Grid did, which was different to other projects, is to work out how to bring parties and interventions together to collaborate.

Alice Springs has a strong history of solar energy innovation and many smart minds have considered this idea. It is accepted that the volume of water required to build a large enough hydro plant is beyond what is feasible. A smaller plant could be built, but it would have no material value.

Any technology that relies upon water in Central Australia is naturally problematic because the region is arid and relies upon a finite source of groundwater. This is why hydrogen isn’t an ideal solution in this area of Australia.

Other considerations relating to ideas of this nature are native title and the Sacred Sites Act, governing the protection of the West MacDonnell ranges and other areas around Alice Springs. However, these cannot be considered as barriers given the absence of technical feasibility for this idea.

Alice Springs is already home to a large-scale Battery Energy Storage System (BESS) owned by Territory Generation and installed at the Ron Goodin Power Station. The BESS was commissioned in 2018 and at the time was the largest battery, proportional to the grid it served, in Australia. The BESS is 5MW and cost about $8m. It is optimised for grid support services (such as inertia, as outlined elsewhere) and is not sufficient to support the grid in terms of energy storage. If optimised to provide energy storage rather than grid support the battery could service the energy needs of Alice Springs for no longer than 20 minutes.

The Roadmap to 2030 has considered where new battery energy storage systems could be placed and their functions. It is likely that at least three systems would be needed, at strategic locations around town to support the grid.

There are a number of major challenges. Firstly, voltage: in creating the power system it was always assumed that power would start at the generator and flow towards the consumer. Now we have ‘generators’ through rooftop solar PV installed at houses and businesses, which push power in the opposite direction when feeding into the grid. This has the effect of increasing the voltage in the system, causing unintended outcomes which can result in reduced quality of supply for consumers. The more energy we put in at a consumer level, the more significant voltage management becomes.

Another condition of a reliable energy systems is that enough inertia is maintained to cope with unplanned events, such as a cloud coming over and rapidly reducing solar generation, or perhaps someone driving into a power pole. Inertia is the capacity for an object to remain in motion. In traditional power systems spinning generators have provided inertia and thus an ability to resist disturbances, giving the system time to respond to changing conditions. One of the reasons Future Grid placed emphasis on the integration of household batteries into the network was because of their potential for providing virtual inertia in certain circumstances. The level to which we can increase the amount of solar in the system is limited by our ability to provide a mechanism to offset the required inertia.

Inertia and operational reserve (generation capacity that is online, controllable and ready to respond to meet demand) act like a shock absorber. The more renewables you add into the system, the bigger that shock absorber needs to be, which starts to become very expensive. So, the question is: are there other ways to provide that shock absorption into the system, such as batteries or other support mechanisms? This was part of what Future Grid was investigating.

Finally, a characteristic of the Alice Springs grid that differentiates it from many other grids is its isolation. Alice Springs doesn’t have anywhere else to which it can push surplus energy or draw upon additional energy when our network is under stress. There are plenty of isolated grids and stand-alone power systems servicing remote communities in Australia, but Alice Springs is an unusual size and regulated. This is unlike most other large grids, which link a variety of types of generation (such as coal, wind, hydro, solar) which can be adjusted to help maintain balance. A larger number of consumers is also helpful to maintain a stable system as traditional modes of generation struggle to operate at minimum loads. Alice Springs faces isolation, low loads, and fluctuating solar generation which makes it a challenging system to manage.

The maximum output capacity of all residential DPV systems in Alice Springs is estimated to be 23 MW, and historical generation data suggests in the order of a 9% contribution to overall consumption. Distributed PV (DPV) and utility-scale Variable Renewable Energy (VRE) accounted for 13% contribution.

Of that 13%, the Uterne Solar Farm which is located to the south of Alice Springs town centre has a maximum output capacity of 3.8 MW, historical generation data suggests in the order of a 3 – 4% contribution to overall consumption.

Fossil fuel-based generation produced 87% of annual volume.

The story starts more than a decade ago when the question being asked was whether or not there would be interest and uptake of renewables. The underlying assumption was that the uptake would happen at levels which meant the core operation of the grid would remain largely the same. However, uptake of renewable energy technology in Alice Springs has been particularly strong, and today the system within which the generation and delivery of energy operates in Alice Springs - the government system, the technical system, the regulatory system – has been tailored to a set of responsibilities and outcomes which are no longer consistent with the likely direction of the future energy system. It doesn’t mean the system we have is wrong, it’s just not necessarily optimised for the future. As a consequence, the requirement for a systems-level project that considers how all these factors can best work together has emerged.

Alice Solar City (2008-2013) served to drive uptake of rooftop solar. Such is the community’s ongoing enthusiasm; we now need to enable the grid infrastructure to support the continued ability for the community to install solar. There have been locations in Australia, particularly WA, where solar installations have been brought to a halt (e.g. Broome) and a move to Distributed Energy Resources (DER) is underway to enable further rooftop solar installations (e.g. Carnarvon and Onslow). In mid-2021 it was revealed Onslow had become the largest town ever to be operated (for a total of 80 minutes) on 100% renewable energy, as part of the DER project run by Horizon Power. Horizon is a Project Partner of Alice Springs Future Grid, and the Future Grid team travelled to Perth to learn directly about Horizon’s technical trials.

Another aspect to consider is that many people talk about “the market” and how it can be used to drive change. However, the energy market is a subset of the power system; it’s not the whole system. The power system includes everything that sits around that market including technical standards that determine how things are done and the regulatory framework that sets out rights and responsibilities. That system is changing because technology is driving change in the roles and responsibilities of different entities. Future Grid was a systems project seeking to determine what is the right system for the future in Alice Springs.