Due to the Coronavirus 2019 (COVID-19) pandemic social distance became a necessary strategy adopted in order to curb the fast-rise of infection. However, this strategy adopted by the government has impacted the socio-economic activities and lives of citizens as such new adaptive measures had to be put in place to cope with the pandemic. Accordingly, this study explores the relationship between the current COVID-19 pandemic on hydropower and energy sector in relation to Carbon dioxide (CO 2 ) emission reduction. This paper employs a systematic review of secondary data grounded from document reports and existing literature to explore the trend of COVID-19 pandemic on hydropower and energy sector in relation to CO 2 emission reduction. Findings from this article offer empirical evidence toward the impact of COVID-19 on hydropower and energy sector in relation to CO 2 emission decrease during the pandemic. More importantly, findings from this study discuss the relationship of COVID-19 on energy sector, impact of COVID-19 on the hydropower sector in comparison to other renewables, impact of COVID-19 and oil demand, and connection of COVID-19 on CO 2 emission reduction during the lockdown. Finally, implications are provided to guide policy makers in making decision toward sustainable energy production and CO 2 emission reduction.

Generally, low flow in rivers occur as a result of extended period of dryness which is likely attributed to drought. Drought is a natural occurrence as an outcome of reduction in precipitation in a region for a long time. Hence, low flow is a growing concern as there are possibilities of more reduced flows in rivers. However, reservoirs can be utilized to mitigate negative effects on the supply of water in dry periods and supply water for other purposes. This study aims at verifying how the low flow condition of Glomma River in Norway has been progressively sustained by hydropower reservoirs. Water Evaluation and Planning Systems (WEAP) software was used for modelling the natural streamflow condition of Glomma River, which is the longest river in Norway, using two unregulated sub-basins within the Glomma catchment. Findings from this study presents that the period between January and March are critical periods in Glomma River. Results show that the values the annual minimum low flow gotten from the three gauges suggest the flow after regulation has increased significantly as opposed to before regulation. The daily average flow is simulated by WEAP to be an average of 100 m3/s during the low flow periods and an average discharge of 350 m3/s during the summer. However, the result indicates that the flow in the summer has reduced by 80% in majority of the years. In addition, Nash Sutcliffe efficiency (NSE) for the two sub basins used for this study was 0.9 and 0.76, respectively. Also, the calculation of the coefficient of determination (R2) resulted in 0.85 and 0.78 respectively for the two sub basins. In particular, findings from this study presents evidence on the low flow condition in Glomma River prior to its regulation and how the regulation has sustained the flow.