Most people would think the scorching heat of the past few days would represent the best time for solar photovoltaic systems. However, it’s more complex than that.
As Europe’s temperature has risen, the solar power industry has been affected as well.
High temperatures of over 40 degrees Celsius (104 degrees Fahrenheit) were recorded in the U.K. last week for the first time ever.
There was significant weather-related disruption in the United Kingdom during a time when other parts of Europe suffered from a heatwave that caused fires, delays to travel, and even death.
On July 20, Solar Energy UK reported that in the month of July, the country’s solar power output had met a quarter of the UK’s power demand. They added that over the course of 24 hours, solar power provided an estimated 66.9 gigawatt-hours, or 8.6% of the UK’s power needs.
According to Solar Energy UK, the U.K.’s solar capacity reaches its optimum output at temperatures of approximately 25°C. “For every degree either side of that, performance drops by about 0.5%,” the company says.
In a statement, Alastair Buckley, who is professor of organic electronics at the University of Sheffield and leads Sheffield Solar, said this was “why we never see peak output in midsummer — peak national output is always in April and May when it’s cool and sunny.” Sheffield Solar project, part of the university’s Grantham Centre for Sustainable Futures.
As evidence of Buckley’s point, the current record for solar generation in the U.K. stands at 9.89 GW, which was reached on April 22, 2021, according to Sheffield Solar.
According to Solar Energy UK, last week’s temperature was far higher than 25C, but overall, there didn’t appear to be too many problems. However, a significant ramp up would be needed before major problems arise.
It cites three factors affecting the temperature of panels: the sun’s radiation, ambient air temperatures, and the cooling effects of wind. to lose 20% of their efficiency, considered significant, the factory would need to reach 65°C.
Chris Hewett of Solar Energy UK, the company’s chief executive, says that the prospect of hotter summers occurring more frequently does not concern him. The spring is marginally better for efficiency, but essentially, if you have more light, you produce more solar power, he said last week.
“Solar panels work all over the world. The same technology we use on our rooftops is used in Saudi Arabian solar farms.”
Increasing temperatures have not only affected solar power in Europe, but other forms of energy as well.
This week, it was reported that a nuclear power plant in Switzerland lowered its output in order to prevent the river that cools it from reaching dangerous temperatures.
According to Swiss broadcaster SRF, Beznau has temporarily scaled back operations, resulting in decreased water temperatures in the River Aare, which is safe for the region’s many aquatic lifeforms.
Companies engaged in renewables have reported that weather conditions can affect their output. For example, wind speeds can be affected by weather conditions.