Annex XV: Maintenance Works and Decision-Making for Hydro Facilities (2016 - present)


This new Annex XV expands on the work of Annex XI (completed 2016), which covered the renewal and upgrading of hydropower facilities.

This new Annex focuses on the decision-making process of asset management. This starts with forecasting changes in soundness of the asset facilities in an individual hydro facility, based on investigations and diagnosis results, and continues with assessment of treatment selections. Options for renewal and upgrading are then considered, which extend life and enhance asset value, within the asset management strategy of both the individual hydro facility and the broader portfolio. Links will be made to some Case Histories previously studied in Annex XI.

The Annex XV objectives has been separated into two categories:

  1. Decision-making Process of Asset Management
  2. Strategic Asset Management of Electricity Utilities

Category-1: Decision-making Process of Asset Management

The condition or soundness of hydro facility assets degrade with time and their performance falls. Hydropower assets are maintained by repetitive repair works and partial renewals until the soundness or performance indices fall considerably and approach the state where major repair work or overall renewal/replacement is required. The owners of hydro facilities estimate the rate and degree of degradation of their facilities based on inspection and test results, and choose the optimum renewal or upgrading methods and timing for their implementation. To estimate the optimum renewal or upgrading methods, it is important to identify and predict future condition and performance trends, so that appropriate treatment methods can be selected and implemented in a timely manner.

Category-2: Strategic Asset Management of Electricity Utilities

Electricity utilities and hydropower owners normally have a number of generation assets in their portfolio. Each of these tends to be rated at a different level of importance, as rated by its power output, revenue value, provision of grid services, etc. Maintenance budgets tend to be allocated in proportion to the importance of each hydropower plant to maximize performance and hence profitability. Similarly, decisions on renewal and upgrading are based on prolonging asset life and maximizing opportunities. Strategic asset management is the process that assesses requirements and allocates operating and capital budgets for the maintenance and economic renewal and upgrading of hydro facilities, with the overall objective to manage risk and maximize value.

This Annex proposes to investigate and document best practices in strategic asset management processes.



 Maintenance Works and Decision-Making for Hydro Facilities (IEAHydro, 2021)

In October 2021, Annex XV published the findings of its international investigation into Maintenance Works and Decision-Making for Hydro Facilities.

The resulting report is in three volumes:

Download all 3 volumes here...

Scope of the Report

This extensive report provides the results of the asset management investigation, led by Japan, which involved the collection and evaluation of good practices to determine the drivers of decision making for hydropower maintenance,and the decision-making process based on those good practices. 

Examples of 196 good practices were gathered from all over the world and were systematically analyzed into six decision-making categories as follows: Overhaul & Repair (O&R), Renewal & Expansion (R&E), Refurbishment, Redevelopment, Abolition and Other

The report focusses on five key drivers in the decision-making processes in advanced hydropower representative countries: Aging, External factors, Asset optimization & review of operation, Disaster and Poor maintenance.

Behind these decision-making drivers are the power demand situation or system unique to the hydropower in each country. This report which consolidated the above information may hopefully serve as a meaningful document for hydropower business operators, E&M manufacturers, and various consulting firms in their future activity. 



IEA Hydro welcomes input into its work. Please contact the Operating Agent, Mr. MURASHIGE Hiroshi for more information about the proposed work of this Annex.


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