Up to 20 percent

Sahara dust slows down solar power production

Anything that blocks sunlight from the PV system slows down electricity production: clouds and even traffic jams(Bild: Kelag)

The cloudy sky is currently reducing the yield of solar power in Upper Austria by up to 20 percent - in Germany it was so bad that even power plants had to be activated. However, because the PV boom is continuing so strongly here, shortfalls are easily compensated for.

Today, the Sahara dust is once again clouding the air over Upper Austria and is annoying PV system operators: on average, 20 percent less yield is coming from the roofs. In Germany, there were even drops of 50 percent at Easter, and in some places power plants had to be switched on again. "For us, these deviations are easily compensated for by the new PV installations. We haven't had to intervene yet," says Christoph Schuh from Austria Power Grid, where the flow of electricity is coordinated nationwide.

300 new systems per week
In March alone, more than 300 solar power systems were put into operation in Upper Austria every week - in the middle of the previous year, the figure was as high as 900 per week. Energie AG, which operates large solar power plants itself, describes the Sahara dust as a "normal fluctuation". Incidentally, anyone who thinks they need to remove the fine layer of dust from the panels should not put themselves in danger: "A rain shower is enough to clean them," say the experts at Energie AG.

1.7 million kilowatt peak

Around 100,000 PV systems are in operation in Upper Austria, and this year the output is expected to rise to 1.7 million kilowatt peak. In purely mathematical terms, this is enough to cover the grid load in Upper Austria.

How Saharan dust works
"Saharan dust also promotes cloud formation because the moisture in the air clings to the dust grains," explains Alexander Ohms from Geosphere-Austria - at Easter and now, a comparatively large amount of desert sand came to us from Africa, but with a stormy change in the weather this evening, this dusty period should be over.

Meteorologists cannot predict when such weather conditions will occur again, but spring and fall are the most "susceptible".