Annex XVI - Hidden Hydro (2018 - present)


The IEA Hydro is undertaking research on “Hidden Hydro” through its collaborative program, covering examples such as:

  • Updating and refining existing hydropower inventories to seek additional feasible hydropower potential
  • Developing and utilizing novel or improved hydroelectric machinery to harvest unused hydropower potential (e.g. low-head applications)
  • Adding power to non-powered dams, as well as distribution infrastructure such as irrigation schemes, water supply schemes and environmental flow units (minimum flows and fish passage flows)
  • Improving the performance of existing hydropower facilities

A significant advantage of “Hidden Hydro” is that, where the potential is associated with existing water resource infrastructure, such as old hydroplants, non-power dams and other water management facilities, there will be little or no incremental environmental/social impact

Research Program Objectives

The overall  objectives for the research program cover:

  • Understanding the potential for sustainable “Hidden Hydro” that has not been addressed through traditional approaches to hydropower development planning.
  • Identifying processes to prepare inventories of the potential for sustainable “Hidden Hydro” 
  • Studying approaches to identify “Hidden Hydro” opportunities through improvements in data gathering, technology innovations, changes in regulation policies and deployment measures
  • Formulating needs for further technology development to maximize the future use of the potential of sustainable hidden hydropower and develop a research and innovation agenda

Research Work Programme

The work program has been subdivided into four sub-tasks.

Subtask 1: Updating Sustainable Hydropower Inventories

  •  Review existing hydropower inventories to identify additional sustainable opportunities, based on new technologies, improved and additional data sets, updated economic criteria, information on regulations and environmental constraints and improved development measures.

Subtask 2: Improving Performance from Existing Hydropower

  • Evaluate existing, older hydroplants for opportunities to improve performance, reduce losses and add power. Use would be made of the information contained in the reports for Annex XI and XV.

Subtask 3: Adding Power to “Non-power Dams” and Water Management Facilities

  • Review opportunities to add power to non-power dams and water management facilities. Many existing dams, built for water supply, irrigation, flood control etc., have potential to add hydropower to their discharge or diversion facilities. There is also potential to replace pressure reducing valves, add power to existing water conduits, irrigation canals and drop structures.

Subtask 4: Hydropower Technology Research and Innovation in the context of “Hidden” Hydropower opportunities

  • Summarize and evaluate innovative research and development initiatives that are contributing to the action areas defined in subtasks 1 to 3 and develop a future oriented research and innovation agenda.

At the completion of each subtask, the results will be presented in terms of findings, conclusions and recommendations for next steps.



December 2018 - Kickoff meeting, Brussels

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