Italy’s snowpack deficit could drive gas-fired output in 2024

LONDON (ICIS)–Another year of snowpack deficit on the Italian Alps could hamper water reservoirs stocks and the Po river’s levels over summer months.

In addition, warmer temperatures expected ahead could cap snow precipitation, Francesco Avanzi, researcher at Italy-based Center for Environmental Monitoring (CIMA) research foundation told ICIS.

This could impact hydro power generation margins in Italy if water reservoirs levels drop as a result of the snowpack deficit, potentially resulting in higher gas-fired generation needed to balance the Italian power system.

Lower snow-water volumes on the Alps, and particularly in the Po river basin, also mean the levels of Italy’s main river could be lower over the hottest summer months, a potential risk for the cooling systems of nearby combined-cycle gas turbine (CCGT) plants.

HYDROPOWER AND CCGT

Hydropower generation typically peaks in the second and third quarter of the year, when snow melts and water reservoirs reach their highest levels.

Although the third quarter normally sees lower hydropower generation than the second quarter, it is also the period that see the highest power demand amid strong air-condition use.

Italy has almost 23GW of hydropower generation capacity and roughly 59GW of thermal power capacity, mostly from CCGTs, according to grid operator Terna.

In 2023 to date, hydropower accounted for 15% of Italy’s power mix – the largest proportion from a renewable source – versus 52% from thermal power.

Hydro generation over the two quarters is driven by reservoir fullness, which in turn impacts gas-fired generation as more supply is needed to compensate for lower hydro power output, or vice versa.

SNOWPACK DEFICIT

In a report published on 14 December, CIMA indicated that Italy currently has a 44% deficit of snow water equivalent (SWE) volumes, a measure describing snow’s water content. On the Alps alone, the deficit is equal to 34%.

According to the research foundation, the “situation is reminiscent of previous years”, although the picture is currently better than in the winter 2022-2023, when the deficit for the Italian Alps stood at 67% as of 16 March 2023.

The Po basin’s deficit is 36%, similar to that of the two other major Italian snow hydrology basins, those of the Adige and Tevere rivers.

EU Copernicus forecasts suggest average precipitation but warmer temperatures over the rest of winter.

“Warmer-than-normal temperatures could have two negative effects on snow water resources: preventing the development of new snowfalls (even with above-average precipitation), and secondly, cause a premature melting of the already existing snowpack” Avanzi told ICIS, noting that this dynamic was already widely observed in 2022 and 2023.

Avanzi added: “The issue is not only how much it rains, but also how hot it is”, noting that in many areas in Italy, November 2023 was up to 1°C warmer than in the last decade.

“Our Alps are missing about a third of the recent snow water resources for this period of the year, and we are preparing to experience much hotter and drier days than normal at least until Christmas” Avanzi said.

CIMA noted that SWE volumes were slightly higher in the Valle d’Aosta region and on Central Alps in the Lombardy region, and pointed out that the levels on the Swiss side of the Alps were even better.

This is also important because water reservoirs and hydroelectricity plants in Switzerland depend on SWE volumes in the region, as do hydro plants along the Rhone river basin in France and EDF’s nuclear power plants of Bugey, St Alban, Cruas and Tricastin, which use the Rhone river water in their cooling systems and therefore depend on its level and temperature for operating efficiently. In past summers, particularly during heatwaves, lower Rhone river levels and warmer temperature of its water meant some of these plants had to force a stop or reduce their electricity output.

Note: Snow water volume graphs published with the permission of CIMA Research Foundation