Here comes the sun: the future of solar energy
“Improving efficiency of solar cells is really important because that directly drives the cost,” says Professor Kylie Catchpole. “If you want to use solar to make things like hydrogen to replace fossil fuels you need to bring down the cost of electricity.” Photo: Jamie Kidston/ANU
by Megan Dingwall, ANU Reporter Deputy Editor
Solar energy is having its moment in the sun. What’s next for the technology that powers it and how do we get more people to use it?
It’s not surprising many residents in White Cliffs choose to live underground. The conditions are extreme. Summer days frequently top 40 degrees Celsius in this opal mining desert outpost about three hours’ drive from Broken Hill. It doesn’t rain often.
It’s a part of the world that feels the full force of the sun’s power, receiving an estimated 3,000 hours of sunshine per year. And it’s the perfect place to harness it.
In the 1980s, White Cliffs’ remote location and, at the time, lack of power supply made it a prime candidate as the base for an experiment. ANU would build a solar power station for the town.
White Cliffs Solar Power Station, opened in 1981, initially operated as a solar thermal power plant. It was trailblazing technology, led by Professor Stephen Kaneff.
Fourteen paraboloidal dishes captured the sun’s energy to heat water and produce steam. This powered the engine to drive the generator and create enough electricity to supply some houses and most of the town’s facilities, including the school, hospital, post office and streetlights.
In 1997, the station was converted to photovoltaic (PV) technology, which uses semiconductors to absorb sunlight and convert it into electricity.
It was connected to the New South Wales grid and White Cliffs became the world’s first commercial solar power station. It ceased generating in 2005 but remains an attraction for visitors.
Reaching for the sky
The White Cliffs experiment proved the potential of solar energy. In the years since solar has become the leading source of renewable energy in Australia and more than 30 per cent of homes have rooftop panels using that same PV technology.
Making solar technology cheaper and more efficient is now a key focus for researchers, including Professor Kylie Catchpole from the ANU School of Engineering.
A physics graduate who moved into solar research to combine her work with a passion for the environment, Catchpole is part of team of experts at the University developing ultra-high efficiency solar cells and setting new records for the amount of energy they can generate.
“Improving efficiency of solar cells is really important because that directly drives the cost,” she says. “If you want to use solar to make things like hydrogen to replace fossil fuels you need to bring down the cost of electricity.”
Decades ago, solar modules had efficiencies of about 16 per cent, Catchpole says. Now, silicon solar cells reach about 25 per cent. In February 2023, ANU researchers achieved an efficiency of 30.3 per cent for a ‘tandem’ solar cell, stacking a cell made from the common mineral perovskite on top of traditional silicon.
“We’re working to get to the point where it could be commercialised.”
It’s all connected
While solar technology has evolved, a lot of infrastructure has yet to respond to the changes in energy production. The amount of energy generated outside the electricity sector reached 17 per cent in 2021, of which 7 per cent was from small-scale solar PV.
One of the puzzles facing researchers working on the expansion of renewable energy is how solar, wind and storage can be integrated into the electricity grid. Our “very static energy system” will transition into something quite different, Catchpole predicts.
“We’ve had certain assumptions about where energy is generated in a very centralised, standard way. But we’re going to have a much more distributed system. We’re looking at how you design these systems to be low-cost and resilient.”
Batteries will also play an important role in optimising transmission. The Battery Storage and Grid Integration Program at ANU is researching neighbourhood batteries, which experts say have “the potential to transform the energy system in Australia”.
Everybody needs green neighbours
The growth of solar in Australia has been rapid. An aerial view of almost any town reveals solar panels on the roofs.
Solar PV overtook wind as the largest contributor of renewable energy in 2019, was the fastest-growing generation type in 2020 and increased by 31 per cent in 2021.
“Solar is going to completely dominate energy supply in the future,” Catchpole says. “If you look at the new electricity capacity that is being installed around the world, the largest single component is solar.”
One of the drawcards is the cost. It’s about the cheapest energy option available. But what else motivated more than three million Australian households to put solar on their roof? And how can that uptake be increased?
Sarah Boddington is a PhD scholar at the ANU Crawford School of Public Policy researching the circumstances that lead people to adopt lower carbon practices and the influences of social norms and identity.
“We live really high carbon lifestyles and so while you can get big carbon reductions from transitioning from fossil fuels, the cumulative impacts of Australians making everyday changes also add up,” she says.
A strong influence on people’s behaviour is their environment and the infrastructure around them, as well as social norms, particularly through what Boddington calls ‘the neighbour effect’.
“One of the highest predictors for whether or not you’ll have solar panels is whether the houses around you have them.”
People can also be motivated by saving money, future-proofing in anticipation of widespread energy transition, and even achieving energy sovereignty.
“Environmental impact is a really important motivator for some people, but not all,” Boddington says. “It isn’t often front of mind when people are making day-to-day choices around things like household energy, transport and diet. They are doing what’s available, what’s normal and what’s habitual.”
The policy push
The Albanese Government has committed to reducing emissions by 43 per cent by 2030 and reaching net zero by 2050. Part of its plan is to ensure more Australians can access solar power.
“The government is probably one of the most important players in making this uptake really fast,” Boddington says. “The first thing is financial assistance.”
Feed-in tariffs, where households are paid for any electricity they supply into the grid, and subsidies to offset installation costs help speed things up, Boddington says. But there are equity concerns.
“We need subsidies for lower-income people to make sure they can also access this technology. We’re already seeing people who can’t access affordable energy because of the increase in power prices and that gap is widening.”
Some higher-income households were able to afford solar earlier and received higher feed-in tariffs, Boddington says. They also used subsidies to install larger systems than they otherwise would have bought, and therefore get even more benefit from the higher rates.
Facilitating access to solar for renters, apartments and housing with body corporates is another policy challenge, as is supporting strategies to influence energy-saving behaviour, Boddington says.
There’s also a role for government in helping to activate the neighbour effect by bringing people together to access information and streamlining the purchasing and installation processes.
“Making it as easy as possible to get them to the point where they’ve got the new technology in their home is really important.”
Up to the challenge
With the energy transition under way and more ambitious climate targets set, the need for people with the skills and expertise to achieve them is growing. That demand stretches across a range of fields such as engineering, policy, economics and sociology, Catchpole says.
“All of these different areas need to come together to actually make this transition happen. And when we say this has to happen by 2050, that’s within the careers of our undergraduate students,” she says.
“That gives you the perspective of what we need to do in terms of educating the next generation to make sure we solve these problems.”
This story was first published in The ANU Reporter.