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EU smart hydropower initiative passes milestone at COP26

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The United Nations Climate Conference in Glasgow marked two years since an ambitious energy innovation initiative funded by the European Union was launched at COP25 in Madrid.

The four-year XFLEX HYDRO initiative, demonstrating how smart hydropower technologies can deliver a low-carbon, reliable and resilient power system, is now at its mid-point and on-track to deliver results in 2023.

The €18 million joint project by 19 leading utilities, equipment manufacturers, universities, research centres, consultancies, including the International Hydropower Association (IHA).  

The initiative will show how hydropower plants can deliver enhanced flexibility and system support services (ancillary services) to balance power grids and accommodate more variable renewables, such as wind and solar power, being brought into the power system.  

The project is testing technologies across seven sites in Portugal, France and Switzerland, including pumped storage, reservoir storage and run-of-river plants.  

In the two years since the €18 million EU-funded initiative was announced at the last United Nations Climate Change Conference (COP25), the first phase of initial studies on each of the six demonstrations has now been completed and two are underway. The remainder are expected to start by early 2022.  

In addition to the demonstrations, the project has also progressed activities relating to assessing the future requirements of the European power grid; and the cost-benefits and social-environmental impacts of the demonstrations.

At the launch in Madrid, Mr Patrick Child, then Deputy Director-General for the European Commission’s Directorate-General Research and Innovation, said: “Combining the excellence and expertise of 19 partners from across Europe, the XFLEX HYDRO project will test innovative solutions based on renewable energy sources that will provide greater flexibility and sustainability to the energy system.

“The project aims to increase hydropower’s potential in terms of plant efficiency, thereby boosting electrical power systems and enabling plant and system operators to operate more successfully in electricity markets. This can make an impactful contribution to European renewable energy objectives and policies.”

The technological solutions being demonstrated by the project are: 

  • Digitalisation tools (the project’s Smart Power Plant Supervisor or SPPS): the SPPS aims to reduce maintenance needs and plant outage time, increase efficiency and minimise stresses on equipment under increased flexible operation. This will ultimately support hydropower plant operators in their decision-making regarding the provision of flexibility services to the grid.
  • Integration of advanced control for a battery storage system: hybridising a battery storage system at a run-of-river hydropower plant, with the aim of providing extended flexibility and fast response services to the grid and increasing plant availability.
  • Integration of pumping and generating power regulation using Hydraulic Short Circuit (HSC): through the tandem operation of pumping and generating modes, HSC can enhance the power regulation services and operating ranges offered by pumped storage hydropower plants.
  • Integration of Doubly Fed Induction Machine (DFIM) variable-speed technology: aiming to extend operating range and add flexibility capabilities for the grid, while also improving annual efficiency and residual lifetime. Enhancing the power regulation range by running DFIM in HSC mode is also being assessed.
  • Integration of Full-Size Frequency Converter (FSFC) variable-speed technology: upgrading hydropower potential by integrating FSFC variable-speed technology, using its high flexibility capability and enhanced functionalities for hydropower plant operation.

An update on the project was given at the recent World Hydropower Congress, and recordings of the presentations can be viewed online.

Short videos explaining the Grand'Maison, Vogelgrun, Frades 2, Alto Lindoso & Canicada and Z’Mutt demonstrations are available online.  


Technical whitepaper and roadmap to advance knowledge and energy policy

The results of the demonstrations will inform a white paper in 2023 on how hydropower plants can apply the project’s technologies. The paper will also address how to maximise the performance of plants through improved efficiency and high availability.  

An accompanying roadmap will set-out the main options for enhancing the European hydropower fleet to contribute to the increased flexibility of the European power system, with policy and market recommendations.  

Flexibility tool, guidelines and plans to support market uptake  

A flexibility tool factoring in cost-benefits, socio-environmental impacts and short- and long-term market scenarios is being developed to support decision making by plant owners and technology providers.

Guidelines for the sector including policy and market recommendations for the industrial deployment of the flexible technologies will also be produced in 2023.

The project results will have implications for the global power sector.

For more information about the project and to sign-up for progress updates, visit

Follow the project on LinkedIn and Twitter @xflexhydro

‍The Hydropower Extending Power System Flexibility (XFLEX HYDRO) project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 857832.