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Global warming has made climate change more and more extreme around the world. In addition to the ecological environment and people's quality of life, even solar power efficiency is subject to its impact. According to MIT scientists, for every 1°C increased in the average global temperature, the solar power generation would drop by 0.45%.
For solar modules, the number of hours of sunshine is as important as the temperature in their environment. Soren Lange, an expert in solar energy, explained that solar modules convert light into electricity. Instead of converting heat into electricity, hot weather will reduce conversion efficiency. It is possible that solar energy would thrive better in a sunny but cold region.
The solar cell structure basically consists of bonded P-type and N-type semiconductors. This structure is called a p-n junction. When a cell absorbs sunlight, the p-n junction generates an electron-hole pair. When the built-in electric field is applied, the excited electrons and holes move in opposite directions, thereby generating current and voltage. However, if the temperature increases, it will speed up the recombination speed of the electron-hole pair and reduce the power generation.
This is also one of the reasons why floating solar energy has been receiving so much attention. Solar modules can optimize the power generation efficiency and performance by the cooling effect of water, thereby increasing the overall power generation. This attribute of solar power suggests that the technology has a higher potential in power generation in a colder environment.
However, the carbon dioxide concentration will continue to rise, if the greenhouse gas emissions could not be reined in. The average temperature will rise by 1.8°C in 2100. By then, the amount of solar power will be affected. According to the study of MIT, the annual energy output (kWh per kWp) will decrease by 15KWh, and by 50KWh in some regions. The impact on the southern United States, southern Africa, and Central Asia will be the most severe.
The MIT Solar Research Laboratory team pointed out that for every 1°C increased in the average global temperature, the solar power generation would drop by 0.45%.
The team also pointed out that new solar modules will also bring new hopes. The new materials of the solar modules may be more resistant to the temperature. The papers published by the team pointed out, materials such as cadmium telluride has a higher bandgap, about 1.45 eV. It matches well with the solar spectrum. Therefore the decrease in efficiency is significantly smaller.
Provided that the future solar modules are capable of withstanding high temperatures, governments and societies still have to commit themselves to reduce carbon emissions. Ultimately, global warming is the sword of Damocles hanging over our planet and everything on it. Should we fail to avert this looming disaster, not only nature and wildlife, but also nations and societies will be put at risk of a series of historically unprecedented catastrophes.
- A hotter planet will make solar power less efficient
- Global warming will hit solar panel performance
Read the original TechNews article by Daisy Chuang