European Union (EU) targets for decarbonisation and a greater share of renewable energy in the power system, are being supported by a new €18 million project, XFLEX HYDRO. The energy innovation initiative has been inspired by ambitious EU targets for a 97 per cent share of renewable electricity in the European power generation mix by 2050. This target is called for in the high renewables’ scenario of the European Commission’s Energy Roadmap 2050.

The four-year, EU-funded project is showcasing hydroelectric technologies that can provide increased flexibility to the power system. Flexibility is important to balance the intermittent nature of variable renewable energy (VRE) sources, primarily wind and solar power.

An important aspect of the XFLEX HYDRO project is supporting market uptake through accurate information about the cost-benefits and socio-environmental aspects of the enhanced flexibility technologies that are being demonstrated by the project. These technologies cover smart digital controls, enhanced fixed- and variable-speed units, hydraulic short circuiting, and hybridisation with an electro-chemical battery. 

Two Flexibility Benefits Optimisation Tools (FLEXBOTs) are being developed and will be validated against each XFLEX HYDRO demonstration project. One tool will be focused on optimising asset operations and the other will support investment decisions.

To assess profitability, short- and long-term market scenarios will be considered. The tools will provide insights to inform investment decisions relating to the modernisation of existing plants and the design of new facilities. 

SuperGrid Institute is leading this work, which will also result in the development of guidelines for the hydro sector, and policy and market recommendations for the replication and scale-up of the XFLEX HYDRO technologies across Europe and the rest of the world. 

Other project partners contributing to the workstream are: Alpiq, EDP Centre for New Energy Technologies (EDP CNET), EDP Energy Production Management (EDP P), Electricity of France (EDF), the Atomic Energy and Alternative Energies Commission (CEA), Andritz Switzerland, GE Hydro, Voith Hydro, INESC TEC – Institute for Systems and Computer Engineering, Technology and Science, Zabala Innovation Consulting, and the International Hydropower Association (IHA). 

The FLEXBOTs tools will support hydro plant owners and operators to make investment decisions about new flexible technologies. Credit: EDF and XFLEX HYDRO project / EU Horizon 2020 / Photographer Mathias Magg


To date, SuperGrid Institute’s focus has been the development of a methodology for costing the CAPEX and OPEX of the XFLEX HYDRO technologies. This has been a joint effort by SuperGrid Institute and INESC TEC and will be one of the pillars of the technologies’ cost benefit analyses. 

Quentin Boucher, Electricity Market Specialist at SuperGrid Institute, says: “We have collaborated with the project partners, including utilities and manufacturers, to finalise the cost methodology.

“This has been documented in our first report, Common methodology to assess costs of hydroelectric flexible technologies, due to be released later this year. The report not only explains the methodology that will be used to forecast investments and operational expenditures related to the implementation of these technologies, but also outlines the impacts of these upgrades on existing facilities.

“Over the next couple of years, the project partners will apply the methodology, specify impacts, look for key parameters, and compile relevant data to evaluate the flexible technologies’ costs and benefits.”

SuperGrid Institute will now increase its focus on market optimisation for the technologies. This is the core of the financial assessment and aims to assess the long-term profitability of these technologies in Europe. 

“We will consolidate data on the different electricity markets in Europe to prepare the development of the profitability optimisation tools necessary to carry out the cost-benefit analyses of the technologies,” says  Boucher. “Making sure the technologies developed by the XFLEX HYDRO project are economically viable and meet the market’s needs is crucial to the success of the initiative.”

SuperGrid’s second report, Market hypothesis and cost-benefit analysis methodology for hydroelectric flexible technologies is due in early 2021.

EDF’s Vogelgrun hydro plant in France is testing the hybridisation of a fixed-speed Kaplan turbine with an electro-chemical battery and smart (SPPS) controls, as part of the XFLEX HYDRO project. Credit: EDF and XFLEX HYDRO project / EU Horizon 2020 / Photographer Mathias Magg


On the environmental and social assessments, IHA is currently preparing for these to be performed by sustainability assessors. A summary report compiling the results of the assessments will be completed by early 2022.

Richard Taylor, strategic consultant on the XFLEX HYDRO project, who is managing the assessments, says these will be done using a tool based on Hydropower Sustainability Good International Industry Practice.

“The Hydropower Environmental, Social and Governance (HESG) gap-analysis tool will enable the standardised checking of each flexibility technology in relation to E&S impacts. Any gaps against good practice will be addressed through a management plan,” he says.

“The focus of the assessments will be on the identification of any impacts, or risks, brought about by the introduction of flexible technologies at each demonstration site. The emphasis will be on occupational health and safety, community safety and any alteration to the hydrological conditions.”

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