Conducting thorough weather analysis is essential for understanding in the short-term whether a project is performing as it should be, based on the available resource.

Extreme Winter Weather Hurts 2015 European Solar Performance

Francesca Davidson | Vaisala Energy


Significant performance decreases of between 5-10% were experienced in Europe's largest solar markets, following sub-par solar irradiance levels and harsh weather conditions throughout H1 2015, according to Vaisala, a global leader in environmental and industrial measurement.

While irradiance levels improved considerably in the second quarter of the year for some key markets in Western Europe, German project operators continued to see below average performance throughout the entire first half of the year.

This analysis is supported by a pair of European Solar Performance maps released today. Vaisala's Q1 & Q2 performance study assesses the impact of short-term weather variations on the production of European solar assets by illustrating deviations from long-term average irradiance across the continent.

In doing so, it highlights significant variability in quarterly resource levels and emphasizes a clear requirement for asset owners and project operators to regularly evaluate and address plant performance. Likewise, following extreme weather patterns in early 2015, including heavy snowfall, hail, and high winds, Vaisala has stressed the importance of effectively deploying maintenance and repair crews to mitigate the impact of associated production shortfalls.

Vaisala's irradiance and weather analysis shows that Germany, a clear leader in the European solar sector with over 39 GW of installed capacity, was significantly impacted during the entire first half of the year by below average irradiance. Italy, France, the U.K., Spain, and Belgium - other markets with a high concentration of operational solar capacity - also saw production shortfalls of up to 10% due to harsh weather. This situation was exacerbated by a delay in the arrival of warm, dry spring conditions, a common occurrence in years with above average snowfall.

However, these five countries recovered in the second quarter with irradiance levels 5-10% above average, brought on by a high-pressure system over northwestern Europe. This caused many countries to see sunnier than normal conditions while Spain and much of the Mediterranean experienced record warm temperatures.

Despite improved conditions in the second quarter, the U.K. still saw rainfall 31% above average in May while damaging winds, hail, and even isolated tornadoes swept across Germany in late April and May.

Conducting thorough weather analysis is essential for understanding in the short-term whether a project is performing as it should be, based on the available resource. It also allows both distributed and utility-scale generators to effectively deploy maintenance and repair crews when problems - such as inverter issues or heavy snow load on panels - reduce production when resource data clearly shows the sun was shining.

"Not only does extreme weather necessitate a robust understanding of the root causes behind production deviations," said Gwendalyn Bender, Energy Assessment Product Manager at Vaisala. "It also makes it even more critical for operations and maintenance teams to make wise budgetary decisions and anticipate the kinds of conditions in store for them."

"For example, with the aid of forecast data feeds and specialized sensors that evaluate snow and ice, these teams can make a more informed decision on whether it is prudent to send out crews for snow removal. After all, if warmer weather or heavy rain will clear snow naturally or if another heavy snowfall is expected, hiring costly manual labor to remove it the day before is not money well spent."

To download Vaisala's Q1 & Q2 European Solar Performance maps, please click here.


About Vaisala
Vaisala is a global leader in environmental and industrial measurement. Building on 78 years of experience, Vaisala contributes to a better quality of life by providing a comprehensive range of innovative observation and measurement products and services for chosen weather-related and industrial markets. Headquartered in Finland, Vaisala employs approximately 1500 professionals worldwide and is listed on the NASDAQ OMX Helsinki stock exchange.

The content & opinions in this article are the author’s and do not necessarily represent the views of AltEnergyMag

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