AUSTRALIA
Sharing is power: do the neighbourly thing when it comes to solar
25 million households have solar panels
University of South Australia
Australian researchers have found that households with solar panels could boost their returns by selling surplus power directly to their neighbours, known as peer-to-peer (P2P) energy sharing, helping to stabilise the electricity grid and negotiating a better price than retailers currently offer.
Worldwide, around 25 million households already rely on solar panels, with forecasts predicting 100 million by 2030. In 2024, the world installed an estimated 597 GW of solar power, a 33% increase compared to 2023.
Australia has one of the highest rates of solar panels per head of population, with almost 40% of Australian houses (4.1 million homes) equipped with panels. The country's embrace of renewable energy has a downside, however. Due to the enormous amount of energy being produced, Australia's electricity grid is now overloaded with excess energy, driving down the feed-in tariff for most households, with some now questioning the economic value of solar.
In a bid to make it more attractive and encourage the uptake of renewable energy, the Federal Government has recently implemented a $2.3 billion scheme to subsidise the installation of home batteries, but a new study shows that adding battery storage doesn’t always deliver extra benefits.
A collaboration between the University of South Australia (UniSA) and Deakin University has compared four different energy models that could help households and energy policymakers design more efficient, community-based solar systems.
The research, published in Renewable Energy, explores the technical and economic benefits of integrating batteries and P2P energy sharing into grid-connected residential photovoltaic (PV) systems.
Using real-world data from a 10kW solar-powered home in Geelong, the study simulated energy generation, consumption and sharing across four models over 12 months, including interactions with three neighbouring consumers.
The models included:
- Peer-to-grid (P2G) – exporting excess energy to the grid
- P2G with batteries – storing surplus energy before selling to the grid
- Peer-to-peer (P2P) – sharing surplus energy with nearby householders at an agreed price
- P2P with batteries – storing energy for self-use, then sharing remaining surplus with neighbours
Lead author UniSA researcher Dr Kevin Wang says the findings show that P2P energy sharing delivers significant benefits compared to traditional grid export arrangements, particularly when feed-in tariffs are low.
“Under current conditions in Victoria, the feed-in tariff is less than 5 cents per kilowatt hour, while the retail price is around 28 cents. Selling surplus PV energy directly to neighbours at a mutually agreed price in between can be more profitable for solar householders and still cheaper for buyers,” Dr Wang says.
Local P2P energy sharing also improves grid stability, balancing supply and demand, because less surplus energy is exported to the grid, which is primarily built to distribute power rather than receive it.
The results showed:
- Batteries boost self-consumption but not profits: Adding a 5kW battery lifted self-consumption to 22% and reduced grid imports but did not help the neighbour. Due to the high initial purchase cost of batteries, the householder did not generate any profits.
- P2P energy sharing reduces grid reliance: Neighbours who participated in peer-to-peer energy sharing saw their grid electricity consumption drop by more than 30%
- No batteries or P2P energy sharing: The householder exported almost 12,800 kWh to the grid annually, with self-consumption rates of just 14.6%
- Batteries plus P2P energy sharing: P2P energy sharing with a 5kWh battery raised self-consumption to nearly 38% but reduced the surplus available to neighbours because battery charging took priority.
- Optimal battery size matters: The shortest payback period – 12 years – was achieved with a 7.5 kWh battery under the P2P model.
- Sensitivity to market: The study’s sensitivity analysis revealed that factors such as equipment costs, discount rates and energy sharing prices significantly influence the financial viability of PV-battery systems.
“Our modelling revealed that under current conditions, P2P energy sharing coupled with a 10kWh battery could deliver the highest return – $4929 – for solar owners over 20 years,” Dr Wang says.
“In contrast, all peer-to-grid scenarios resulted in negative returns over the same period due to low feed-in tariffs and high battery costs.
“Battery size proved critical. Systems with oversized batteries saw returns diminish due to higher capital and maintenance costs and reduced surplus energy.”
Co-author Professor Chunlu Liu from Deakin University says the study highlights a trade-off between battery use and community sharing.
“When batteries are used, they benefit the solar owner by reducing their grid reliance, but this can limit the amount of energy shared with neighbours because they are fully charged before any surplus energy is shared. The challenge is to find a balance that works for everyone,” Prof Liu says.
The researchers suggest that further gains in solar self-consumption could be made by integrating other technologies, such as heat pumps or thermal storage, to absorb excess PV energy that would otherwise be exported.
With Australia’s solar uptake the highest in the world, the authors say that models like P2P energy sharing could help relieve pressure on the grid while improving the economics of home solar.
“Our analysis shows that if P2P energy sharing prices are set between the feed-in tariff and retail rates, both sellers and buyers can come out ahead,” according to co-author Professor Mark Luther. “But market rules and technical systems need to support these transactions at scale.”
The team hopes their work will inform policy and investment decisions as the energy sector transitions to decentralised, low-carbon systems.
‘Technical and economic analyses of grid-connected residential PV considering batteries and peer-to-peer energy sharing’ is authored by Kevin Wang, Mark Luther, Peter Horan, Jane Matthews and Chunlu Liu. DOI: 10.1016/j.renene.2025.123494
Journal
Renewable Energy
Method of Research
Data/statistical analysis
Subject of Research
Not applicable
Article Title
Technical and economic analyses of grid-connected residential PV considering batteries and peer-to-peer energy sharing
Macquarie’s solar silver solution strikes gold
University partners with Lithium Universe to commercialize new recycling technology for solar panels
Macquarie University
Macquarie University has licensed breakthrough silver extraction technology to ASX-listed Lithium Universe in a partnership that could transform how Australia recycles solar panels.
The silver trapped inside Australia’s discarded solar panels equates to the country’s biggest silver mine, according to researchers who have developed a new way to extract this valuable metal without destroying the panels.
Dr Binesh Puthen Veettil and Dr David Payne are co-leaders of a team from Macquarie University’s School of Engineering who hold a provisional patent for a precision method which extracts silver components, while still leaving other materials intact for reuse.
This technique complements the team’s patented solar-panel microwave-powered delamination technology, also licensed by Lithium Universe under the commercial partnership.
“We can selectively remove silver without touching other metals like aluminium, and without impacting the silicon cells and other components,” Dr Veettil says. “Our solution is like a pressure washer for removing silver.”
The technology addresses a growing waste problem as more and more solar panels reach the end of their 25-year lifespan. The Australian Energy Council states global solar panel waste will reach 60-78 million tonnes by 2050, with Australia alone accumulating one million tonnes by 2035.
Each panel contains about 20 grams of silver worth A$36 (US$23), but conventional recycling methods destroy the panels to extract it. Only 15 per cent of used solar panels are currently recycled.
Rising demand for silver
As industries globally from electronics to renewable energy compete for silver, demand is surging by seven per cent annually, projected to reach around 20 million kg in 2025.
The market faces a shortage of 3.3 million kg this year as mining struggles to keep pace.
Silver prices have more than doubled from just under US$600 (A$920) per kilogram in 2018 to US$1250 (A$1913) per kilogram today.
ASX-listed Lithium Universe has acquired global rights to the Macquarie technology through an exclusive licensing agreement worth more than A$500,000 (US$320,000) over 20 years.
Precision Extraction Process
The Macquarie team’s Jet Electrochemical Silver Extraction (JESE) technology works like a precision cleaning tool, directing a thin stream of weak acid directly onto the silver in solar panels, dissolving the metal in seconds while leaving everything else untouched.
“The silicon wafer remains intact and uncontaminated, making it suitable for reuse in semiconductor manufacturing,” Dr Veettil says.
Traditional recycling grinds entire panels into powder then uses harsh chemicals, destroying all components. The Macquarie method preserves glass sheets and silicon wafers while extracting pure silver.
The silver extraction technology works alongside the team’s innovative solar panel delamination, licensed by Lithium Universe in July, which uses microwave energy to separate glass, silicon and other components without grinding or a high-temperature furnace.
Together, these technologies can recover intact glass sheets, preserve silicon wafers and extract pure silver from each panel, with greater than 77 per cent current efficiency and with minimal waste.
Lithium Universe will complete research and development before commercial deployment is in place, by 2032, paying annual licensing fees and sales royalty.
“We have built a strong, solutions-focused partnership combining Macquarie’s world-class research with our commercial vision,” says Mr Tan.
“Together, we are delivering a breakthrough recycling solution that recovers high-purity silver while preserving wafer integrity,” he adds.
Dr Veettil says the technology could potentially later expand to extract other valuable metals including gallium, indium and copper from discarded solar panels.
“This collaboration shows the impact university research can have when paired with industry vision,” says Professor Sam Muller, Executive Dean of the Faculty of Science and Engineering.
“As Australia moves toward its target of 82 per cent renewable energy by 2030, we’re not just solving the solar waste problem – we’re creating a new resource stream to meet worldwide demand.”
Watch a video outlining the new technology here: https://www.youtube.com/watch?v=_0l6lWpwrfE
Dr Binesh P Veettil is a Senior Lecturer in the School of Engineering at Macquarie University.
Method of Research
Commentary/editorial
No comments:
Post a Comment