Management Of Hydropower Plants Research Articles

Optimizing ecological benefits in weekly-regulated hydropower plants: A framework integrating power market information

The production of hydropower has profound impacts on the sustainability of downstream river ecosystems. However, current studies often overlook the crucial role of power market information in this process. This study aims to investigate the ecological impact of power market information on the downstream river of weekly-regulated hydropower plants. Additionally, it explores strategies to enhance ecological benefits while minimizing the adverse effects on power generation. To achieve these, this study proposes an ecological management framework for the downstream river of hydropower plants. This framework effectively models the scheduling of hydropower plants in the context of the power market and tracks changes in ecological indicators to assess the ecological consequences of power market information. Through a case study conducted in the Wujiang River Basin, we analyze the impact of electricity price characteristics on release flow and downstream ecological benefits. We also provide recommendations for optimizing generation strategies to enhance ecological benefits while minimizing revenue losses. The findings of this study can serve as a reference for the ecological management of hydropower plants, ensuring the sustainability of power generation.

Economically optimal hydropower development with uncertain climate change

Climate change affects the planning, construction, operation and management of hydropower plants in various ways. Evaluating hydropower generation with nonstationary climate changes is important for planning electric power infrastructure development. For a new hydropower plant with climate change, specifying too large a reservoir may result in excessive investment if the future becomes drier, while too small a reservoir may cause insufficient utilization of hydropower resources. Whether to build a new hydropower station at once or build it dynamically in stages over time is challenged by uncertainty in future conditions. This study proposes a planning method for developing a flexible hydropower construction schedule to adapt to long-term uncertain hydrology with climate changes. Projected uncertain nonstationary hydrology scenarios were developed first, and Bayes’ theorem is used to update the probability of each scenario based on observed hydrologic conditions over time. A profit maximization model integrates stochastic dynamic programming and linear programming for a cascade hydropower system to evaluate hydropower plant expansion and how to build it dynamically with uncertain nonstationary climate conditions. In this, stochastic dynamic programming evaluates and prescribes inter-stage reservoir upgrades and linear programming prescribes inner-stage hydroelectric power generation. The case study of Jinsha cascade hydropower system in China’s Yunnan province illustrates the method. The intensity and trend of climate change effects on streamflow directly affect the optimized results. If streamflow decreases in the future, the best strategy is to build a small reservoir initially, without future changes. If streamflow increases in the future, it is better to build a small reservoir first, and gradually increase capacity according to observed changes in streamflow and economies of scale in capacity construction. If there is no clear trend in streamflow change, it is also better to build a small reservoir at first, then decide whether to expand the reservoir according to future observed changes in streamflow. This method with uncertain nonstationary climate change and upgrading adaptively with observed hydrology usually produced better results than optimization for a deterministic nonstationary hydrology.

Active landslides in the Rogun Catchment, Tajikistan, and their river damming hazard potential

The region of Tajikistan where the Rogun Hydropower Project is currently under construction has experienced large and catastrophic slope failures in the past, often triggered by earthquakes. Co-seismic slope failures are thus common and pose a high hazard potential; however, to date, no specific analysis of slope activity in this area has been presented in international journals. Here, we present an inventory of active landslides identified through satellite imagery analysis and in particular by exploiting space-borne differential radar interferometry. Surface displacements provide the basis for the detection of active slope instabilities, which are then further classified by using geomorphological indicators visible in optical satellite imagery. Additionally, the proximity of active landslides to tectonic lineaments, as well as regional seismicity, is analysed to investigate potential relationships and to provide an integrated river damming hazard potential. The results show that approximately 31% of all detected landslides would have a high damming hazard potential upon catastrophic failure, highlighting the importance of such phenomena for efficient long-term land use planning and management of hydropower plants.

Experiments with sediment replenishment in a residual flow reach: Comparison of field datawith laboratory experiments

Hydropower is an important pillar of the electricity production in Switzerland and its extension is planned in the next decades. Therefore, a more sustainable management of hydropower plants is needed. Sediment replenishment combined with artificially-triggered flood pulses are gaining increasing interest to restore residual flow reaches. In the Sarine river in Switzerland, such a measure was conducted. Mimicking laboratory experiments for the first time, four deposits, totaling 1000 m3 of sediment, were added to the river downstream of Rossens dam. Some 489 pebbles were equipped with RFID PIT tags and distributed among them. After the flood pulse passed, 57% of the tags were re-located. The maximum detected travel distance of a pebble was 284 m. Some deposits were eroded, while others resisted. Due to a limited submergence, mainly lateral erosion was observed. Nevertheless, erosion of deposits as well as deposition of eroded material in clusters resulted in the same scheme as observed in laboratory experiments which could be validated with this field experiment.

Hydropower production and environmental regulation: opting for a performance-based tax approach

This paper discusses the case for reforming the actual mechanism for charging water abstractions for hydropower production in Italy and proposes to introduce a performance-based environmental fee. This should be able, on the one hand, to internalize the environmental costs that hydropower production causes and, on the other, to stimulate producers to opt for more environment-friendly management of hydropower plants. We think, in fact, that the re-issue of several expired hydropower concessions represents an opportunity to redefine the taxation system to which hydropower is currently subject to, in order to introduce finally a form of environmental taxation coherent with the Water Framework Directive. In particular, the proposed fee is a real environmental tax, as it aims at changing the environmentally impacting behavior by increasing the marginal cost of damaging river ecosystems. Therefore, it is equitable, as it does not tax all producers the same way, but according to the impacts that their production generates. Finally, it is immediately applicable, as it is based on the successful experience of performance-based regulation in several other sectors.

Climate Change Impacts on Hydropower Management

Climate change affects hydropower production by modifying total annual inflow volumes and their seasonal distribution. Moreover, increasing air temperatures impact electricity consumption and, as a consequence, electricity prices. All together, these phenomena may lead to a loss in revenue. We show that an adequate management of hydropower plants mitigates these losses. These results are obtained by resorting to an interdisciplinary approach integrating hydrology, economy and hydropower management in an interdependent quantitative model.