Assessment of climate change impact and incorporation of environmental flows on hydropower production: a case study of the Chhukha Hydropower Project in the Wangchu River Basin, Bhutan | |
| Author | Denkar |
| Call Number | AIT Thesis no.WM-18-16 |
| Subject(s) | Climatic change--Bhutan--Wanchu River Basin Water-power--Bhutan--Wanchu River Basin Chhukha Hydropower Project Bhutan |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering in Water Engineering and Management, School of Engineering and Technology |
| Publisher | Asian Institute of Technology |
| Series Statement | Thesis;no. WM-18-16 |
| Abstract | The major development project is for hydropower in Bhutan which are highly sensitive to the changes in climate. Climate change can have a great impact on the hydropower generation in Bhutan as all the hydropower plants under operation are run of the river scheme which are fully depended on the runoff. The operation of reservoir changes the natural water flow by reducing the flows of the downstream river which plays a critical role in maintaining the ecological system of the river. Climate change is likely to alter the river flow regime significantly and consequently may pose a serious threat to river ecosystem. The study focuses on assessment of climate change impact on hydropower generation and the degree of hydrological alteration caused by Chhukha dam operation in the Wangchu river, Bhutan. The hydrological model HECHMS was used to generate runoff for baseline and under climate change scenario. Three RCMs ACCESS, CNRM and MPI under RCP 4.5 and RCP 8.5 was bias corrected using linear scaling bias correction method. Aphrodite precipitation and CPC-NOAA temperature data set were used due to limited observed data. The reservoir simulation model HECResSIM was used to simulate the hydropower generation for baseline and under climate change scenario. The Indicator of Hydrological Alteration employing the Range of Variability Approach method was used to estimate the minimum monthly flow requirement and the degree of hydrological alteration caused by hydropower operation. The key factors of climate change are increase in temperature and variability of precipitation. The average discharge during dry season increased and decreased during the monsoon season as per predictions for the future. The average annual power production will slightly decrease in future period whereas for winter season there is an increase compared to baseline. However projected hydrological change is dependent on the choice of RCMs and anthropogenic emission scenarios. The inclusion of minimum monthly flow requirement in the reservoir operation has not much impact on hydropower production but the degree of hydrological alteration can be reduced. The hydrological alteration was projected to increase in future under both climate scenarios. |
| Year | 2018 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis;no. WM-18-16 |
| Type | Thesis |
| School | School of Engineering and Technology (SET) |
| Department | Department of Civil and Infrastucture Engineering (DCIE) |
| Academic Program/FoS | Water Engineering and Management (WM) |
| Chairperson(s) | Shrestha, Sangam;Babel, Mukand S.;Duc Hoang Nguyen;Namgyal, Lhendup ; |
| Scholarship Donor(s) | Asian Development Bank; |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 2018 |