Charles Darwin University

The Northern Territory (NT) Government is supporting the Charles Darwin University (CDU) to carry out research related to renewable energy. The government has funded three research projects with CDU:

  • cost effective maintenance of remote hybrid mini‐grid systems
  • modelling future solar energy production from households and businesses in the Greater Darwin Area
  • bioenergy for PV hybrid electricity generation.

Cost effective maintenance of remote hybrid mini-grid systems

For remote communities in the NT, access to reliable power supply is critical for their economic and social development. While diesel fuel continues to play a fundamental role in providing reliable power supply, there is a push for increasing solar / diesel / battery hybrid mini‐grids in order to maximise use of renewables and reduce cost. In spite of the increasing usage of hybrid mini‐grids in remote regions, sustainability of these systems depends on the cost of maintenance over the lifetime of these systems. Servicing and maintenance of such systems is difficult and has been one of the major problems for widespread implementation. Significant opportunities exist for improving operational and maintenance costs through better monitoring of systems.

This project will consider the development of predictive maintenance (PM) technology for optimising maintenance and procurement activities for remote hybrid mini‐grids. Predictive models (based on machine‐learning algorithms) aim to assess future outcomes based on analysis of past and present data. Predictive maintenance would allow for greater information about mini‐grids that can help head off the chances of major equipment faults and the subsequent costs incurred. It would also increase the quality of services with the aim of keeping the asset fully functioning for its lifetime. Using predictive models allows real‐time fault identification, remote assessment and troubleshooting of problems and maintenance of remote mini‐grids in a cost effective way. Data gathered remotely will inform investment planning in system upgrades. The web‐based technology will also support a standardised system for maintenance, management and procurement of components for the mini‐grids.

Three hybrid mini‐grid systems owned by NT Parks and Wildlife, situated at Ormiston Gorge, Watarrka (Kings Canyon) and Palm Valley in Central Australia, will be used to develop and test the predictive maintenance technology developed by CDU.

There are hundreds of remote mini‐grids in the NT, on communities, outstations, parks, and pastoral sites. This research project aims to make installation of hybrid mini-grids a more attractive proposition and help support existing systems through lower operational and maintenance costs.

The main aims of the project are:

  • to increase monitoring capabilities for remote hybrid mini‐grids
  • to develop predictive algorithms to detect and forecast failures before they occur
  • to overcome the high maintenance costs of remote mini‐grids through predictive maintenance
  • to increase the life span of the assets
  • to improve the quality and reliability of service provided by mini‐grid systems
  • to measure economic savings achieved by remote predictive maintenance of small solar PV mini‐grid systems as compared to regular maintenance.

Modelling future solar energy production from households and businesses in the Greater Darwin area

As most dwellings in Darwin are not yet using rooftop PV, there is huge potential for an increase in the residential and business sectors. Understanding how best and most cost-effectively to achieve an increase in the adoption of rooftop PV will be essential if the target of 50% renewables is to be met by 2030. However, in order to increase the rate of PV adoption, better knowledge about motivations and barriers to adoption is needed.

Understanding householder and business behaviour around PV uptake will allow the implementation of the policy settings most likely to lead to an increase in households and businesses taking up PV. Scenarios that might affect the dispersion of PV in Darwin will be developed in collaboration with the NT Government, the NT Business Council, real estate agencies, demographers, solar energy retailers and other stakeholders who can inform the research. The scenarios can include changes in existing market stimuli (incentives, rebates, feed-in-tariff), changes in availability and costs of associated technologies (for example, storage), changes in markets and retail policies and changes in the Darwin population. The scenarios will be underpinned by the uniqueness of the NT in terms of its transient population, low home ownership and energy consumption patterns, all factors that need to be understood in relation to PV uptake for making more realistic predictions.

Knowing the future demand for and uptake of PV is required for predicting future grid requirements and the contribution behind the meter renewable energy will likely make towards the Territory’s renewable energy target. Once complete, this research will help the government target the policy and programs best placed to deliver the optimal levels of behind the meter renewable energy to meet the target by 2030.

Bioenergy for PV hybrid electricity generation

With the amount of sunshine the NT receives, solar power is expected to be the major contributor across the Territory towards reaching the renewable energy target of 50% by 2030. However, solar power can only be generated during the day and is subject to the volatility of the weather. Passing clouds can sharply reduce the amount of light incident on the panels leading to drastic drops and then surges in the power supply as the clouds pass causing instability. This will be particularly acute during the wet season in the Top End. A method is needed to smooth out the abrupt changes to ensure a high quality, stable power supply. A lot of attention has been given recently to battery storage which is an effective and relatively simple way to store electrical energy that can be released on demand. While the cost of battery storage is expected to come down and will likely be a dominant enabling technology for the increased uptake of solar energy, it is not considered a long-term sustainable solution as there can be environmental impacts during manufacturing and disposal.

This project will investigate the use of biofuel as part of a hybrid power generation system. The power generated using biofuel will be used as a supplement to stabilise the power supply during weather events and operate when the sun is not shining leading to a constant output. The project will create the knowledge that could lead to the development of commercial small-scale waste-to-biofuel technology in the Territory.