The transition to renewable energy from multiple sources is indisputably good for our planet, but can be problematic for traditional electricity grids based around a central power station. A new research project in Queensland aims to create a different approach for using distributed renewable energy resources.
CQ University’s Dr Umme Mumtahina’s research project Shaping Queensland’s Grid for Sustainable Growth of Renewables in Rural Communities hopes to mitigate challenges rising from a rapid increase in rooftop solar, particularly in rural areas.
There are two potential issues with integrating solar into the existing grid system: the costs of maintaining and upgrading the existing lines, which can stretch up to 200 kilometres between small lightly-loaded substations in rural areas, and voltage rise issues caused by customer generated energy flowing back into the grid.
Leading the way in rooftop solar
Australia has the highest uptake of domestic solar panels in the world, at around 30 per cent, and renewable energy is steadily increasing its ability to meet energy demand. At one point in October last year, for example, renewable energy provided two-thirds of energy in the main grid.
Dr Mumtahina said the highest capture of solar power was during the middle of the day, often when people are at work, so production can sometimes outweigh consumption.
“If this amount of energy goes back into the grid it will cause a huge imbalance. Something needs to be done – we need some type of storage and other elements such as static synchronous compensation (STATCOM),” she said.
Load management
Working with ElexSys Energy, her project hopes to prove that by installing STATCOM units in conjunction with battery systems, voltage rise issues can be alleviated.
“The ElexSys system combines innovative hardware and software to regulate voltage. Distributed energy storages will also be added to the grid to store energy during daytime and pay it back at night to maintain the network,” she said.
“By integrating rooftop solar PV and battery energy storage systems, the reliability and power quality of the electricity supply to rural communities will be enhanced. This will also help to build resilience against natural disasters.”
Future-proofing the grid
Dr Mumtahina believes the Queensland grid system is currently coping with the amount of solar coming back into the system, and changes are being made to prepare for the higher penetration of renewable energy. However, this is not a long-term solution.
“The Queensland Government has a 70 per cent renewable energy target by 2032 and internationally the target is net zero emissions by 2050. This means we have to act quickly. It’s not that they are not doing something; they are, but it’s within the existing grid.”
She said that many of the state’s traditional networks experience frequent outages due to storms, bushfires and other natural events, and the rural lines are themselves a fire risk. “The cost of maintaining those lines in service is increasing. These costs represent a significant and growing ‘bow wave’ of capital and operating costs for the industry, which will be passed on to the general community via network charges.”
The ultimate aim of the project is to create sustainable independent micro-grids at a community level. Dr Mumtahina said that part of her project was to use STATCOM units to capture data that will indicate the size and amount of systems needed based on population, usage and renewable energy generation. The system is also capable of integrating other forms of renewable energy such as wind.
Her project is a relatively new concept in Queensland and she is working with the Winton Shire Council to trial the system in the rural community over the next three years. If successful, the systems could be rolled out to rural areas throughout Queensland and beyond.
“I have seen a lot of growth [in renewable energy] in the last few years, so when I was having a discussion with my colleagues and also an industry partner, they were saying that [the conversion to renewables] is going to happen fast. In fact, it’s high time to do something,” she said.
Increasing support for microgrids
Late last year the Federal Government announced eight grid-scale batteries, ranging from 200-300 megawatts and including grid-forming inverter technology, will be installed in Victoria, Queensland, South Australia and New South Wales by 2025 to help stabilise the grid and store renewable energy.
However, increasingly, towns are choosing to go it alone and produce and store their own energy away from the grid. Examples include Heyfield, in Victoria, which is currently trialling a microgrid, while WA’s Western Power created a 100 per cent renewable microgrid for the town of Kalbarri last year. Coober Pedy has been necessarily off-grid for years due to its remoteness but mainly relied on diesel; more recently renewables have contributed up to 100 per cent of the town’s power.
The Australian Government’s Regional and Remote Communities Reliability Fund has invested around $50 million over five years to 2024 to support feasibility studies looking at microgrid technologies to replace, upgrade or supplement existing electricity supply arrangements in off-grid and fringe-of grid communities located in regional and remote areas. It said that microgrids can represent more reliable, secure and cost-effective energy supply options for regional and remote communities in Australia.
Dr Mumtahina’s research project has been awarded $240,000 in funding over three years through the Advance Queensland Industry Research Fellowship program administered by the Department of Tourism, Innovation and Sport (DTIS) and has also been backed by industry partners Elexsys Energy with another $357,512 in funding to ensure the success of the innovative project.
The Advance Queensland Industry Research Fellowships program is part of the Queensland Government’s Advance Queensland strategy to ‘support Queensland’s innovators, scientists and entrepreneurs to create the industrial engines needed to make Queensland a global innovation economic powerhouse and supports the creation of jobs now and into the future’.
Climate Smart Engineering 2023 (CSE23) will be held 29-30 November 2023 at the Melbourne Convention and Exhibition Centre. Call for abstracts and registrations are now open.
Abstract submissions close 11.59 pm AEST on Wednesday 12 April 2023.