The sunniest areas of the world appeared to be ideal for installing solar panels. we were wrong
As sun-drenched countries like Pakistan undergo their own energy transitions, we have more and better information about how extreme environmental conditions affect the performance of solar panels. A hint: This is not good news for these countries.
Context. Solar energy is an important part of the transition to renewable sources, but it is not happening at the same pace around the world. The United Kingdom, which has an average of 1,400 hours of sunshine per year, has installed more photovoltaic capacity than all the countries in Africa combined, despite the fact that the Sahara region has about 4,000 hours of sunshine per year.
With the goal of tripling the world’s renewable capacity by 2030, understanding how environmental factors affect solar energy performance will be increasingly important for connecting countries with severe climates.
A study published in Renewable and Sustainable Energy Reviews analyzed how environmental factors affect the efficiency of solar panels around the world. conclusion? It will be necessary to adapt photovoltaic technology to the most extreme local conditions.
temperature. High temperatures reduce the efficiency of solar panels because they affect the flow of electrons in photovoltaic cells. Researchers say that for every 10 degrees Celsius increase in ambient temperature, panel output decreases by 4 to 5%.
They argue that one solution would be to implement passive (such as natural ventilation) and active (such as water cooling) cooling systems to reduce this impact, especially in regions such as India, Africa and the Middle East. An alternative: gels that absorb water at night and release it during the day.
dust. Other pollutants such as dust and aerosols block direct sunlight, reducing the amount of energy reaching photovoltaic cells. The study says dust can reduce the efficiency of panels by up to 60%, especially in desert areas like the Sahara.
The solution will surprise no one: regular cleaning of solar panels to maintain the efficiency of the photovoltaic cells, either by passive (self-cleaning coatings) or active (mechanical or robotic cleaning) methods. A promising technology to solve this is electromagnetic waves.
Snow. Snow isn’t always bad. This increases the albedo of the environment, which can increase solar output by reflecting more light onto the panels. And when it melts, it leaves the glass covering the module clean.
However, if the heat from the solar panels is not enough and ice covers the cells for too long (for example, in very cold locations), the effect is the opposite. The solution is to design an installation that minimizes ice accumulation on the panels and takes maximum advantage of the increased albedo.
Customized solar panel. Each region has unique conditions that affect solar performance. Sometimes they are not directly related to climate: California wildfires reduced photovoltaic production by 30% due to smoke. And several hailstorms have wreaked havoc on solar parks.
But as countries with extreme conditions such as the high temperatures of the Middle East meet their emissions commitments, technologies and strategies will need to be developed to maximize the performance and economic feasibility of solar projects. Tools like renewables.ninja allow you to explore these impacts globally and plan the installation of solar panels with accurate data.
Image | Pxhere (CC0)
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