In Austria, country of blue gold, hydraulics disrupted by the climate

They are building a new power station in the mountains capable of storing energy above the Salzburg village of Kaprun, at a wild and inhospitable altitude, even in summer.

Their veritable cathedral, stuffed with technology, is buried under a backdrop of white peaks and vertiginous dams, flown over by eagles and trampled by ibexes.

At the foot of the statue of Sainte-Barbe, patron saint of dangerous trades, we have just celebrated the end of the heavy excavation work in oppressive tunnels, vibrating with the comings and goings of trucks.

The aim is to expand existing facilities by 2025 to absorb peaks in electricity consumption and react to precipitation that has become increasingly capricious and irregular.

Rising temperatures are also causing drought and accelerating the melting of snow or ice, threatening river supplies.

"The distribution over the year will change: we will have less water in summer and more in winter," said Klaus Hebenstreit, executive of the semi-public company Verbund, the country's main electricity producer.

“We want to prepare ourselves as well as possible” for these new challenges, he underlines. Hence this gigantic storage power plant project, capable of producing on demand thanks to energy reserves.

Exporter turned importer

At the other end of the country, the Freudenau site on the Viennese Danube supplies more than 240.000 households. It works on the water, according to the flow of the rivers.

Its six turbines with a diameter of 7,5 meters are impressive and at the end of the school year, classes on outings come to admire them.

So many facilities that do not emit CO2 during use and are the pride of Austria, even if their impact on ecosystems is not negligible and is regularly denounced by environmental activists.

Exploiting almost all of its rivers with more than 3.100 dams, the country derives more than 60% of its electricity production from this renewable energy source, compared to 16% in the world on average.

But the warming is already being felt and the figures are falling: hydroelectricity generated 42 terawatt hours (TWh) in 2021, down from 45 TWh in 2020, according to Statista.

For the first time last year, this prosperous country - which is also trying hard to give up the supply of Russian gas - had to resolve to... import electricity, a real alarm signal.

This is the result of the succession of "several years of drought", explains Roman Neunteufel, researcher at the Agricultural University of Vienna. "Water levels had never been so low since records began" a hundred years ago.

Europe experienced a year 2022 that was 2,3 degrees warmer than the climate at the end of the XNUMXth century, according to the recent annual report by the United Nations World Meteorological Organization (WMO) and the European Copernicus network. And alpine glaciers have experienced "record mass loss".

Diversification

"If it is not possible to produce a lot because of the low flow rates, it is clear that other resources will have to be used", warns the expert.

In this context, Verbund is investing billions of euros in the extension of its fleet, to improve security of supply and develop alternatives.

“We are diversifying,” explains Klaus Hebenstreit, interviewed in the Austrian capital under an oppressive temperature of 37 degrees. "If water will remain the heart of our activity, we also now have photovoltaics and wind power".

For a country hostile to nuclear power which had bet everything on a seemingly inexhaustible resource and is aiming for 100% renewable electricity by 2030, their development is a headache.

“Solar energy is great in summer,” recalls Roman Neunteufel. "But production is too low in winter, precisely when we need it for heating".

"And with the wind it's even worse: when there is none, production is simply interrupted", according to the researcher.

Accustomed to the image of Epinal of crystal clear water flowing in abundance in green meadows, Austria turns belatedly to the wind and the sun, which represent only 13% of its energy package.