EU may have wide hydropower potential for power balancing

The article has been updated to clarify the impact of climate change and include more details about large-scale dams

• The EU has some untapped potential for hydropower growth – expert
• Growing intermittent renewables will need more balancing capacity like hydro storage
• Climate change could lift hydro costs and could challenge water resources

LONDON (ICIS)–As intermittent supply from renewable penetration increases, hydropower could support balancing needs, mainly through pumped hydropower storage (PHS) plants.

The European Commission Joint Research Centre’s (JRC) energy model suggests a 20% increase in annual hydropower output in the EU by 2050. The model considers the potential of sustainable hydropower in the EU, which will support the balancing of the power system in many countries, hydropower expert Emanuele Quaranta at the European Commission told ICIS.

Key features of future hydropower will be “the provided flexibility and the water and energy storage of the associated reservoirs”, he added.

Quaranta’s study based on 2019 EU hydro generation conditions showed that modernising and improving the efficiency of existing plants would bring a 10% increase in power generation, which could reduce the need for additional capacity, with none or little impact on the environment.

ICIS Analytics shows that in 2024, 254GW of installed hydropower capacity in Europe (including other non-EU countries) should produce 512TWh, making 16% of the total power generation stack. Hydropower capacity across Europe could grow from 254GW to 279GW, generating 543TWh or 10% of the total power mix by 2050 while surpassing the total nuclear power generation amid growing demand needs, according to the ICIS Analytics forecast.

HYDROPOWER POTENTIAL

River and water basins in the EU are home to more than 650,000 water barriers – including small-scale dams – with only 5% currently used for hydropower production, Quaranta told ICIS.

The EU has almost 5,000 large-scale dams above 15 metres, or between 5 and 15 metres with storage volumes larger than 3 million cubic metres, half of them with installed hydropower generation capacity. However, only one-third of the total infrastructures are built exclusively for hydropower generation, with many sites including hydropower as a secondary scope alongside other types of use, like stocking water for agriculture or residential use.

“The average age of hydropower plants currently in operation is 45 years, meaning a large part of the EU’s hydropower infrastructure will need interventions to increase its efficiency and flexibility, sustainability, improve the resilience to climate change and ensure safety,” the expert said.

According to a European Commission JRC study by Quaranta, the hydropower energy return on investment (EROI) is the highest among renewable sources.

BALANCING NEEDS

Battery storage can be used for short-term balancing, typically up to 4 hours, but when insufficient renewable output is prolonged, PSH can guarantee flexibility of power systems.

“PHS can store water energy (with daily, monthly and seasonal storage depending on the installed capacity and reservoir’s volume) more cost-effectively than any other option, and can put and absorb energy available in seconds,” the JRC study indicated.

CLIMATE CHANGE RISKS

Climate change is set to impact the use of hydropower, particularly in southern Europe where the risk of severe droughts is expected to increase over the coming years.

However, Quaranta noted that climate change might impact regions differently, with northern and eastern European countries expected to have increased precipitation levels potentially supporting hydro stocks, while southern Europe could face drier weather hampering water reservoirs and, therefore, electricity production.

“Climate change could shorten the lifespan of hydropower turbines as they would need to operate in a context of dry weather alternating with infrequently but stronger rainfall volumes. Also, the required flexibility needed to support the integration of the highly volatile wind and solar energy generation can increase the stress on hydropower equipment,” he added.

Although climate change seems likely to lift overall maintenance costs for hydropower plants associated with sediment management (more frequent floods could increase solid transport and erosion), new technologies might mitigate sediment deposition issues, Quaranta confirmed