A new study by engineers at UNSW Sydney has revealed that reducing greenhouse gas emissions and atmospheric aerosols can increase the efficiency of solar panels and lower energy costs in the future.
In a paper published in the Renewable Energy journal, the researchers conclude that variations in the climate system, depending on the green policies adopted globally to reduce emissions, will lead to changes in photovoltaic (PV) energy generation.
Their analysis of complex computer simulations, known as Global Climate Models, indicates that the potential efficiency of PV in Australia – as well as North America and most of Asia – would be reduced due to decreased radiation and increasing temperatures. In contrast, the efficiency in Europe would be increased.
Aerosols in the atmosphere can potentially decrease the amount of solar radiation reaching the surface of the Earth. This is further impacted by any rise in temperature, since solar panels do not work efficiently in temperatures above 25 degrees Celsius. When PV efficiency is reduced, energy costs will increase since more solar panels would be required to generate the same amount of energy.
The UNSW researchers have calculated that the difference in costs could be as high as US$12.4 billion (AUD 18.5 billion) per year when comparing a future scenario where little action is taken on greenhouse gas emissions and air pollution, versus a low-emission clean-air ‘green-growth’ roadmap.
Lead author of the paper Alejandra Isaza, a PhD candidate at UNSW working with Associate Professor Merlinde Kay in the School of Photovoltaic and Renewable Energy Engineering, said: “These results aim to contribute to the analysis of future energy storage requirements, help optimise the location of future solar plants, as well as promote the adoption of policies to accelerate the ongoing energy transition and mitigate the climate change impacts.”
“All the computer models show that temperature will rise in the future, but the most optimistic scenario, which is aligned with good climate policies and the uptake of increased renewable energies is also the one associated with lower future costs.”
The researchers used a Levellised Cost of Energy (LCOE) analysis to predict the price of energy produced by a generating PV plant over the course of its lifetime. LCOE is commonly used to evaluate the cost-effectiveness and feasibility of different energy technologies.
“We can see that increased aerosols in the atmosphere reduce the efficiency of PV generation, so that is where we would like to see pollution control measures have a real impact. Those aerosols can be naturally produced – such as ash from volcanic eruptions or dust storms like the famous one in Sydney in 2009 – and there is not very much we can do about that,” Associate Professor Kay said.
“But they are also generated by coal-fired power plants, so if we can significantly reduce emissions from that kind of source and move to cleaner forms of energy generation then we get a better environment and we save money in terms of future PV.”
Analysis was conducted on mono-crystalline silicon and thin-film modules, with the former being more dominant in the market but more affected in a future warmer climate.
Image: Researchers from UNSW say the results of their study will help optimise the potential location of future solar plants. Image from AdobeStock
