2025 → Present
Task 20
Digital Twins in Hydropower 1.0
Background
In recent years, risks caused by climate change are common concerns across the world. This is true for hydropower plants and some are forced to have long-time operation stoppage with recovery works for flood damage with climate change as post-maintenance. In order to protect power facilities, hydropower producers need to analyze potential risks and implement precautionary measures to reduce the risk as far as possible, and to have flood damage mitigation measures such as pre-remodeling works against new hazards triggered by climate change.
There is also a concern of the increase of sediment inflow to reservoirs that might be caused by glacier retreat and intensive rainfall with climate change. So, hydropower producers are requested to maintain power generation function with further optimized reservoir sediment management to secure reservoir capacity.
The theme of this Annex is “Measures to enhance the Climate Resilience of Hydropower”, and a survey will investigate specific measures that hydropower producers should take to enhance the climate resilience of hydropower.
The core survey items are as follows:
- Forecast of potential natural hazards triggered by climate change and evaluation of countermeasures and design criteria for safety check of power facilities
- Countermeasures to mitigate damage to hydropower plant facilities caused by extreme floods
- Reservoir sediment management
Regarding the survey target, scope of the target shall be set according to the framework of river administration in each country.
This Task identifies risks caused by climate change and investigates the countermeasures that hydropower producers should take against flood risks and other risks caused by climate change. Surveys will be conducted among research institutions and hydropower owners/operators. The surveys will make an inventory of probable hazards due to climate change which may endanger power facilities and evaluate the risk mitigation effect of the countermeasures that hydropower producers can take. The surveys will include case histories of flood damaged hydropower plant facilities in each country and they will be reviewed and systematized based on the analysis and evaluation of the risk mitigation effect of the countermeasures. The outputs of the survey will be fed back to hydropower producers and contribute to the mitigation of flood risks in the expanding climate change around the world.
The Task will not address changes in electricity generation caused by hydrological alterations resulting in less or more water or seasonal shifts of the generation.
Objectives
Forecast of potential natural hazards triggered by climate change and evaluation of pre-emptive countermeasures and design criteria for safety check of power facilities
- Amid concerns about an increase of flood damage risks and other risks triggered by climate change, it is necessary for hydropower producers to take measures in order to play the role of ensuring the safety of power generation facilities and the stable supply of electric power. So, power facilities should be designed to withstand events triggered by climate change impacts such as extreme floods based on the proper design criteria and other pre-emptive measures
- Design bases are regularly reviewed and updated according to new hydrological analysis taking into account the effect of climate change. In order to evaluate the current design criteria, it is planned to make an inventory of probable hazards due to climate change which may endanger flood safety and other safety and operational aspects of power facilities. Potential new hazards affecting flood safety may be linked to new potential landslides, glacier lake outbursts with mud flows in addition to the expansion of flood discharge scale and it is necessary to forecast the potential natural hazards for the safety check of power facilities.This survey will summarize the forecast of potential natural hazards triggered by climate change and an evaluation of the design criteria and other mitigation measured for the safety check of power facilities.
Countermeasures to mitigate damage to hydropower plant facilities caused by extreme floods
- Amid concerns about an increase of flood damage risks, it is necessary for hydropower producers to take measures in order to play the role of ensuring the safety of power generation facilities and the stable supply of electric power. In flood damage recovery work, it is required to formulate a recovery plan for power generation facilities and to repair the facilities at an early stage in consideration of the prevention works for similar disasters. In the recovery works against the flood damage, the survey will coordinate the recovery plan based on the damage factor analysis and the challenges in design and construction taking into account economy and construction technology.
- Flood damage recovery is the post-maintenance work against facility damage caused by external factors such as torrential rainfall, but it is also required to take preventive maintenance to mitigate damage in the future. In renewing the power generation facility as preventive maintenance to reduce flood damage, structural examinations for functional enhancement and safety improvement in preparation for the expansion of future damage scale will be coordinated. And the case histories on efficient and labor-saving efforts on operation and maintenance will be reviewed as well.
Reservoir sediment management
- Reservoir sediment management has been important from the perspective of securing effective reservoir capacity for power generation and efficient reservoir operation. So, it is required to remove sediment from the reservoir in addition to the decrease of sediment inflow from upstream.
- Amid the forecast of the increase of flood discharge, it is required to have further optimization of reservoir sediment management on removing sediment concerning the increase of sediment inflow to reservoir.
- Regarding the way of sand removal, in addition to the conventional ways such as reservoir dredging, in-lake transport, sand-flushing through flushing gate embedded in the dam body, sediment bypass tunnel systems are starting to be newly applied. But, there are some problems in the flushing efficiency and downstream environmental impact to be considered. To solve those problems, integrated sand removal by dams located on the cascade in the same basin is proposed as the effective way and a survey will investigate challenges and solutions how each dam is having an initiative in the complex operation based on the integrated management and monitoring.
This survey will coordinate challenges of reservoir sediment management that hydropower producers would tackle.