Arkaroola Wilderness Sanctuary

North Flinders Ranges, South Australia

Stand-alone microgrid, integration of solar and battery storage to reduce generator reliance

BESS System Power and Storage Capacity

  • PV: 99kWp roof-mounted solar
  • Battery storage: 121kWh lithium capacity
  • Inverter/Charger: 60kW, 3Phase
  • Generators: 65kVA and 200kVA (existing)

Project summary

Over the years, Apex Energy Australia has been involved in hundreds of off-grid solar projects, from residential homes to commercial applications in Australia; the bulk of these projects focused on energy generation and supply. Rightly so, a property uses a certain quantity of energy, a renewable system needs to deliver that amount. From time to time, innovative and clever customers would speak with us about optimising the use of their renewable energy, resulting in basic load controls and management smarts built into their off-grid system.

Fast forward to 2021, and with over three decades of in-house experience in off-grid system design and project management behind us, Apex Energy was asked to manage a project that would not only see a renewable energy system deployed but a holistic, top-down approach to energy usage included in the project scope. Under the Regional and Remote Communities Reliability Fund – Microgrids 2020-2021, the Australian Government awarded a successful application for a Sustainable Microgrid and Outback Technology Showcase at the iconic Arkaroola Wilderness Sanctuary. The fund enables a team of specialists, led by Apex Energy Australia, to trial and implement innovative solutions that provide the site with sustainable renewable energy and reduce reliance on external fuel sources.

Project Overview

Eighteen months into the project have consisted of researching, designing, engineering, and evaluating countless equipment options and solutions that address the energy challenges of the village. In 2023 we see the deployment phase of the project take shape, a very exciting stage for all involved. Let us draw a picture of the energy scenario at Arkaroola:

  • Since the creation of the wilderness sanctuary in the 1960s (formerly a sheep station), power has been provided by diesel gensets 24 hours a day, 7 days a week, 365 days per year.
  • The village was once 100% electric. LPG gas was introduced in the 1980s and is used primarily for hot water heating and the commercial kitchen. The goal is again to be 100% electric but from renewable sources this time.
  • Water is precious, with minimal yearly rainfall and relies on unpredictable bore water. Notably, the bore water causes scaling of water infrastructure; hot water storage systems seldom last more than 18 months.

Energy monitoring deployed by Arkaroola Village in 2019 provided valuable insight into the electrical energy requirements of the village. This data validated that heavy usage periods are during the cooler months when visitor numbers are at their maximum and site-wide heating is required. A common misconception is that because Arkaroola is located in an arid, desert-like environment, the time of the year with the highest load would be summer. While loads in summer indeed can be large due to air-conditioning, the high occupancy combined with below-freezing nights make the winter months heavy on energy.

Unfortunately, the peak energy consumption in winter doesn’t match peak solar conditions; in fact, it is the inverse. Energy efficiency solutions were researched and trialled that focused on methods to reduce winter energy consumption while simultaneously optimising the lower quantity of renewable energy generated. The key improvements and technologies that were deployed:

  • Building envelope – Most of the buildings were built in the 1970s, and the insulation was either non-existent or has since degraded. This resulted in the heat created by the heating systems being lost through the ceiling, walls and windows. Improving the thermal fabric of the most energy-intensive buildings aims to reduce heating loads at the time of the day (night) and time of the year (winter) when renewable energy is most scarce.
  • Guest education – Guests to Arkaroola are often unaware of the self-reliant nature of the village and the impact that individual actions can have on power and water supplies. Existing signage around the property educated guests on water saving but didn’t mention energy. To improve this, new signage in every guest room and public spaces encourages individuals to take responsibility for their energy and water usage. This is combined with a live public energy dashboard in the reception for visitors to follow village energy consumption trends.
  • Energy Optimisation – When solar energy is available, we want to ensure it is all used and not wasted. By utilising an Energy Management System, when the batteries are full and excess solar (or generator capacity) is available, smart loads are activated. For example, this could be the smart control of an EV charger or activating an electric hot water system. Heating hot water via solar energy is in itself a form of battery storage, a cheap and safe way to store energy created during the day for use at night.
  • Energy Monitoring – It is hard to improve when you don’t know where you’re coming from. An extensive energy management system will be deployed to monitor energy usage around the site and combine other important variables such as temperature, gas and water usage. Utilising this data will enable more intelligent decision-making and a focus on identified energy-intensive areas of the village that will provide the most valuable outcomes.


Apex solution

The design, engineering and deployment of a solar and battery microgrid, integrated with the existing diesel generator system, is the most significant part of the project. There are many design considerations to consider, from existing infrastructure, site factors, equipment requirements, stakeholder engagement, and communications systems integration, just to name a few. After much evaluation, the selected off-grid system equipment was based on the Australian-made Selectronic SP Pro 120v inverter/charger architecture. The inverter combined 121kWh of lithium battery storage from Spanish manufacturer CEGASA and 99kWp of roof-mounted solar panels. There were many reasons for using this equipment combination:

  1. Australian-made with local support – Arkaroola is a day’s drive from the nearest capital city, and the possibility of an untested system requiring specific service technicians was not of interest to the owner. Confidence in the build quality, robustness, fit-for-purpose, serviceability and having a proven off-grid history was at the top of the list.
  2. Expandability – The ability for the equipment to grow as Arkaroola grows, electrical energy consumption increases, and funding becomes available.
  3. Plug and play – The off-grid system was fully assembled and tested before delivery to the site. This meant the onsite deployment time was kept to a minimum.

The available budget for the microgrid portion meant that the system’s capacity could not meet Arkaroola’s energy needs in the first instance. The system had to be designed to add capacity easily without requiring major system rework. Phase 1 of the system capacities and the associated enabling infrastructure included:

  • 100kWp Solar Array on the Mawson Lodge and Workshop buildings, expandable to 400kWp+
  • 121kWh Lithium Battery Storage, expandable to 363kWh
  • 60kW continuous 3phase battery Inverter/Charger, expandable to 180kW
  • Control integrations with the existing diesel generator system
  • A new village main switchboard to integrate the solar and battery system into the power distribution network
  • Underground cabling to major solar locations
  • A 22kW 3phase public electric vehicle charging station

The daily operation cycle of the system varies throughout the seasons and occupancy rates. Low occupancy in summer can mean on some days, no generator input is required, and higher visitor occupancy periods during winter will mean heavy generator input. In the two weeks since the system was commissioned, preliminary data suggests that diesel fuel consumption has reduced by 50%. Over the next 12 months, a review of the microgrid system and the trialled technologies will take place to evaluate the benefits, successes and learnings of the project.

It is early days in the transition of Arkaroola to renewable energy, and the phase one solar and battery system has laid the groundwork for more renewable penetration in the years to come. The demonstration of smart energy management, the value of energy efficiency and energy reduction for off-grid power systems this project has enabled has been a truly valuable and excellent learning experience for myself and the project team. The environmental, social and financial benefits of renewable energy for remote South Australia are now on display at the Arkaroola Wilderness Sanctuary. Come and see it for yourself!