Solar climbing the Alps

Research conducted by Switzerland’s WSL Institute for Snow and Avalanche Research SLF and the Swiss Federal Institute of Technology in Lausanne has highlighted the potential of PV systems installed in high Alpine regions to reduce seasonal reductions in power generation by solar during winter, due to fog, clouds and lower solar radiation.

According to the study, published in the the journal Proceedings of the National Academy of Sciences, to increase the yield of PV systems at high altitudes it is crucial that placement is able to benefit from high winter irradiance and high ground-reflected radiation and that steeper-than-usual panel tilt angles are used.

“Such mountain installations require significantly less surface area and, combined with steeper panel tilt angles, up to 50% of the winter deficit in electricity production can be mediated,” states the paper.

Satellites helped estimate solar radiation

The researchers claim solar panels on snow-covered mountains may help Switzerland hit targets set by the Swiss Energy Strategy 2050, which envisages closing five nuclear power plants in the nation at the end of their operating life.

“Our study shows that PV systems in the mountains, compared with installations on the roofs of buildings in the Swiss Plateau, are much more capable of overcoming the supply shortfall that will arise as a consequence of abandoning nuclear power because, per square meter, solar panels at high altitudes produce electricity not only in larger quantities, but also when it is needed,” said one of the study’s authors, Annelen Kahl.

The research was based on data collected by remote sensing satellites which helped estimate solar radiation across Switzerland.

“The results show that the energy deficit in a future [dependent on] fully renewable [power] production – from wind power, hydropower and geothermal power – could be significantly reduced when solar PV is installed at high elevations,” the report’s authors added.