A UNSW study on climate change models over 70 years has found that atmospheric aerosol levels and greenhouse gas emissions will significantly impact photovoltaic (PV) energy production and associated costs in the future.
In a paper published in the Renewable Energy journal, UNSW engineers concluded that fluctuations in the climate system would lead to changes in PV energy generation, depending on whether moderate or robust action is made globally to reduce emissions.
Their analysis of extensive computer simulations known as Global Climate Models shows that the potential efficiency of PV in Australia, North America, and most of Asia would be reduced due to decreased radiation and rising temperatures. In Europe, on the other hand, efficiency would be boosted.
Aerosols in the atmosphere have an impact by potentially reducing the amount of solar radiation reaching the Earth’s surface. Temperature rises would exacerbate the damage since solar panels do not perform appropriately in temperatures beyond about 25 degrees Celsius.
Future PV efficiency reduction could increase costs as more panels are needed to generate the same amount of energy.
UNSW researchers estimate a potential cost difference of up to US$12.4bn per year between a future scenario with minimal greenhouse gas emissions and air pollution versus a low-emission clean-air “green-growth” roadmap.
“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,” UNSW School of Photovoltaic and Renewable Energy Engineering Alejandra Isaza said.
Isaza explained that all computer models predict future temperature rise, but the most optimistic scenario, involving good climate policies and increased renewable energy adoption, is associated with lower future costs.
“In contrast, in the worse-case scenarios we have less favourable PV efficiency, particularly in China, because there are less solar resources due to the increased aerosols in the atmosphere, as well as higher temperatures which also has a negative effect,” she added.
The researchers used a Levelised Cost of Energy (LCOE) methodology to forecast the cost of energy a PV facility produces over its lifetime.
Although the researchers recognise that this is a relatively simple technique that does not account for all the costs and factors that influence investment decisions, they highlight that it is a widely used tool to assess the cost-effectiveness and feasibility of various energy technologies.
“What the work shows is that there’s a range of possibilities and it depends on how we move forward in time as to which one could come to pass in terms of the efficiency of PV generation and therefore the associated costs,” UNSW’s Associate Professor Merlinde Kay said.
Associate Professor Kay believes that policymakers and developers should consider the economics and costs of various scenarios when implementing their plans.
“And what we see is that if we keep moving forward developing renewable technologies then we reduce those emissions and also then save quite a bit of money. In contrast, if we are pessimistic and expect there to be less stringent controls on pollution, then that actually costs us more economically.”
“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 explained.
However, she noted that they are also created by coal-fired power plants, so drastically reducing emissions from that source and shifting to cleaner energy generation will result in a better environment while saving money on future PV.
The study also analysed the differences between the two types of PV panels to determine which type would be more beneficial in different future climate scenarios.
Analysis was conducted on monocrystalline silicon (mono-Si) and thin-film modules, with the former dominating the market but being more vulnerable to a future warmer climate.
The research emphasises that further work needs to be done to improve the performance of PV cells at high temperatures to make them more adaptable to climate change.
