Challenges and solutions for a renewable future
Nov 05, 2019
The transition to a renewable energy future is upon us, prompting challenges in power systems across Australia. An isolated grid and enthusiasm for rooftop solar heightens those challenges in the Alice Springs power system.
Experts are working to conceptualise a future grid for the town, which makes the most of our sunny skies. The Intyalheme Centre for Future Energy has been set up to facilitate this transition, as its General Manager Glenn Marshall explains…
It is sometimes said that the only constant in life is change. In the information age, this is acutely evident in certain areas of business – from factory workers impacted by automation, to the democratisation of news through social media. Perhaps nowhere is it more evident right now than in the business of supplying electricity.
We have started transitioning to a renewable energy future, led by hundreds of households installing rooftop solar systems. As with all grids in Australia, utilities must now adjust to manage the changes created by these ‘distributed’ power generators and maintain a reliable grid.
The recent disruption to our power highlights the importance of reliability in our energy supply. The cause of the October 13 outage will not be clear until the results of an independent enquiry are released.
“What we have here is about the most complicated ‘off-grid’ system you will get,” said engineer Clare Paynter, who works for local technical consultancy Ekistica. Ms Paynter was one of the speakers at a recent public event called Our Bright Solar Future: Learning from Our Leaders.
“We’re a small place but we have a lot of different entities that need to work closely together in order for the system to work properly,” Ms Paynter said.
This is the job of Intyalheme – to bring the major Northern Territory energy players together with interstate experts to achieve this transition, and reach the NT’s 50 per cent by 2030 renewable energy target. Intyalheme is a flagship project of Desert Knowledge Australia (DKA) and has received $5 million funding from the Northern Territory Government.
Intyalheme (pronounced in-char-lum) is an Arrernte word, meaning ‘a fire starting up again’. The name alludes to a revitalisation of the strong renewable energy history in Alice Springs, with programs like Bushlight and Alice Solar City putting the town at the forefront of renewable energy innovations.
For those relatively new to town, 2008 saw the launch of the DKA Solar Centre, the largest multi-technology solar demonstration site in the Southern Hemisphere. The same year marked the start of Alice Solar City. The project, which ran until 2013, saw the number of rooftop solar photovoltaic systems in town grow from just two, to more than 700.
When the Uterne solar farm opened in July 2011, it was the largest tracking solar power station in Australia. The tracking arrays at Alice Springs Airport were another first for the Southern Hemisphere. “Visitors are not able to ignore the town’s commitment to solar energy when they drive in from the airport,” the Alice Solar City report stated.
By the time Araluen Arts Centre had rooftop solar installed in 2012, about three per cent of energy consumed in Alice Springs was produced by solar — one of the highest levels in Australia, per capita.
At the moment Alice Springs is averaging about 10 per cent solar input and there are numerous barriers to this increasing. Fixing this is more complex than it might appear but, done well, Alice Springs would once again lead the way. Lessons learned here can be applied to much larger grids including one of the world’s biggest — the east coast’s National Electricity Market (NEM).
One of the many challenges is reducing dependence on gas generators for ‘spinning reserve’, which requires machines be kept on permanent standby in case of technical problems, or clouds interrupting levels of irradiance. Intyalheme is facilitating a partnership between local utilities and national experts to incorporate solar (cloud) forecasting into the system.
Rooftop solar makes economic sense for many households, but new installations contribute to growing fluctuations in the grid. Household batteries could assist the transition, but existing tariffs do not encourage uptake at present.
A reliable power system has technical needs including frequency control, voltage control and system inertia. In Alice Springs these have traditionally been provided through gas generation. The grid-scale Battery Energy Storage System (BESS) at the Sadadeen Valley sub-station is being optimised to contribute to these needs. It is proportionally bigger than Elon Musk’s ‘big battery’ in South Australia.
The transition must be carefully managed if we are to reach a high level of renewable energy penetration, whilst maintaining stability on the grid.
Every grid in Australia is facing similar challenges. Alice Springs has the opportunity to get ahead of the pack.