A relentless heat wave has been burning Europe for over a week. Some countries like France or England reached historical records. High temperatures (40ºC) and hundreds of hectares burned in the south of the continent in countries like Spain, Portugal, Greece. This is a climate phenomenon that has never been seen before. In the midst of all this, Germany, Record amount of electricity from solar energy a few days ago: about 38,174 megawatts were produced from the solar panels and more are expected in the coming days.

many people think they will wear their boots in the sun sector with these extreme waves. Everyone used to say that the hotter they were, the better they would work. This is not so. In fact, the extreme heat is hindering their work.

Do they work better or worse on hot days? The truth is, this record amount of energy could have been much higher had the temperatures been a little lower. Intuitively, warmer, sunnier days, rising temperatures don’t actually equal more energy. hinders the solar panels’ ability to collect. Most panels are tested at an ideal temperature of 25ºC. But above this threshold, the yield drops no matter how bright the sun is.

“The solar panel is a bit like the silicon chip inside your computer, it won’t work if it gets too hot,” said resource scientist Ray Wills. this ABC News article.

Why? Why? To understand this loss of efficiency you have to know how the panels themselves work. as described this Euronews reportThey absorb sunlight with their photovoltaic cells, and the photons absorbed by the panels release electrons from their atoms and create an electric current inside the panel’s semiconductors, creating an electrical circuit. But the hotter the panel, the greater the number of electrons that are already in the “excited” state. This reduces the voltage produced by the panel and lowers its efficiency.

And it’s pretty serious. High temperatures can reduce the efficiency of solar panels between 10% and 25%, According to CED Greentech data. And for every additional degree Celsius, its efficiency drops by 0.5%, According to Solar.com.

well above the optimal level. After calculations and taking 25ºC as the optimum level (the temperature of the panel, not the atmospheric temperature), it is expected that the panel will be at least 75°C on a 45°C day. If the panel is 50°C warmer than optimum, output power will be reduced by about 25%. If it’s 10°C higher than normal you’ll get 5% less performance, which isn’t much, but something to consider. Now imagine what could happen in the middle of a heatwave like what we’re experiencing right now.

real situation. In addition, more people turning on their air conditioners in extreme temperature conditions will increase the demand for electricity. Nowadays, governments have large-scale investments in household batteries that capture the energy produced by roof panels to reduce household energy bills. Will this heat damage those bills? Yes.

It should also be noted that there are thermal solar panels that will not be affected by the increase in temperature. It is necessary to distinguish between different types of solar power generation: solar photovoltaic and solar thermal. As the name suggests, solar thermal harnesses the sun’s heat and works like a coal-fired power station: it boils water and produces steam. But these panels are much rarer, especially in homes, and are considered less reliable for generating electricity.

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