A new UNSW Sydney research suggests that climate change might impact the future stability of grid-connected solar power systems.
The modelling, conducted by UNSW Sydney researchers, shows the magnitude, frequency, and duration of disruptive solar generating events, known as ramps, will shift considerably during the next century. The university noted that the modelling findings might help shape future solar power infrastructure in Australia.
According to UNSW, grid-connected solar power systems, or large-scale photovoltaics (PV), are Australia’s most rapidly increasing renewable energy technology.
Solar energy converts sunlight into electricity, resulting in inherent fluctuation in power generation. Cloud cover, timing, and location can all cause supply and demand imbalances, potentially resulting in power outages or grid failures.
“Solar PV generation is affected by climate factors, which makes it susceptible to climate change. For example, changes to the way clouds pass over solar panels could cause sudden decreases (ramp-downs) or increases (ramp-ups) that can cause voltage fluctuations and blackouts,” School of Photovoltaics and Renewable Energy Engineering PhD Candidate and lead author of the study Shukla Poddar said.
The university noted that renewables account for 35.9% of total electricity generated in Australia in 2022, with solar being the largest contributor to the grid. With significant large-scale PV deployment planned, including the world’s largest solar farm at Powell Creek, Australia, forecasting future ramps is critical for assuring consistent power output as Australia’s reliance on large-scale solar grows.
“Using more variable renewables like solar can impact the stability of the electricity grid as they can provide power intermittently as clouds pass over,” School of Photovoltaic and Renewable Energy Engineering lecturer and co-author Associate Professor Merlinde Kay said.
“So, this work is essential for grid operators, who are responsible for managing and maintaining a reliable electricity network, to understand how these ramp events will change with climate change so they can plan this adoption accordingly,” Professor Kay stated.
The researchers utilised regional climate projections to simulate solar ramps in Australia through 2100 under intermediate and high emission scenarios. The results revealed that ramp occurrences were becoming more prolonged and more common across the east coast and northern Australia, with their magnitude decreasing. These effects are more pronounced when emissions are high, as Australia is now experiencing.
“Overall, it means that we should expect solar ramps to become more common over the next century with climate change, though this does differ between locations and future emissions,” Poddar said.
“For grid operators, it means they need to be prepared with the proper technologies and strategies to manage more regular intermittency issues,” she added.
According to UNSW, mass storage technologies and a more diverse mix of renewable energy sources in the grid can be employed to manage the fluctuations brought on by solar ramps.
“During ramp-up events, large batteries can store excess solar to help reduce the strain on the grid. In a ramp-down event, the stored energy can be fed back into the grid to help compensate for the loss in solar power and maintain grid stability,” Associate Professor Kay said.
“Combining this with renewable energy technologies like wind, which can operate at night, is also essential, and is already working quite well in places like South Australia at The Hornsdale Power Reserve with the Tesla battery powerpack,” she stated.
Another option for minimising power ramps is to build solar farms in strategic areas. The researchers hope that the findings of their study will influence future solar farm developments worldwide, which they will investigate further in future research.
“The framework we’ve developed here to study future ramp events spatiotemporally using climate modelling can be applied to different places around the world to ensure optimum grid operations in the future as the climate changes,” Poddar said.
