New PhD: The renewable energy market can alter river flow regimes

Biowater is proud to announce that Dr. Faisal Bin Ashraf successfully defended his thesis on 29 May 2020. Faisal’s thesis, River regimes and energy demand interactions in Nordic rivers, was well received by the opponents. Dr. Faisal Bin Ashraf is by this our first examined PhD!

Faisal has studied at the University of Oulu in Finland. He has analysed the possible consequences of more renewable energy in the Nordic energy market, with focus on the impacts for hydropeaking and river regimes. (Hydropeaking is a way to operate a hydropower plant: Pulses of water are released to increase power production so that daily peak electricity demand can be met.)

Important questions have been if more renewable energy in the Nordic energy market will increase the need for hydropeaking, and if this again will affect river regimes. If the answer to these questions is yes, then aquatic biology in Nordic rivers will most likely be distressed.

River regimes of Nordic rivers are changing, mainly due to climate change and river regulation. To assess the relative effect of regulation practices and climate change, Faisal studied two adjacent rivers in Finland, the Kemijoki (regulated) and Tornionjoki (pristine), with similar climate and catchment conditions. The hydrological alteration of the regulated river was twice that of the pristine. In the regulated catchment, regulation and climate change seemed to have similar degrees of effect on flow alteration (50% each).

New PhD: Faisal Bin Ashraf

Faisal also used datasets from discharge stations in 150 rivers to analyse short-term water discharge changes in Nordic rivers. The results revealed high levels of hydropeaking in Nordic rivers, with increases especially in the recent few years. This indicated that when we utilise more renewable energy, there will be an increasing need for load balancing in the energy market, and this may again increase hydropeaking in Nordic rivers.

Furthermore, a method was developed to characterize variability in hydrological time series in different periods. It was found that, in winter, sub-daily variations in some large regulated rivers were up to 20 times higher than in free-flowing rivers. For smaller regulated rivers with lower levels of regulation, the variation was highest in summer.

Faisal’s results are important, not least since more frequent fluctuations of river discharge can be stressful for aquatic biology. If the introduction of bioeconomy, with more use of renewable energy, will mean less favourable conditions for aquatic life in our rivers then it is important to be aware of this and implement measures. His findings should therefore be of great interest both to hydropower companies, river basin management boards, and national managers and policy makers within energy and the environment.

Faisal also visited UC Berkeley in the autumn of 2019, to learn more on impacted rivers.

Faisal did his PhD at the university of Oulu, and his supervisors were Professor Bjørn Kløve, Assistant Professor Hannu Marttila, and Associate Professor Ali Torabi Haghighi.