Hydropower Production Potential Research Articles

A Model for Assessing the Importance of Runoff Forecasts in Periodic Climate on Hydropower Production

Hydropower is the largest source of renewable energy in the world and currently dominates flexible electricity production capacity. However, climate variations remain major challenges for efficient production planning, especially the annual forecasting of periodically variable inflows and their effects on electricity generation. This study presents a model that assesses the impact of forecast quality on the efficiency of hydropower operations. The model uses ensemble forecasting and stepwise linear optimisation combined with receding horizon control to simulate runoff and the operation of a cascading hydropower system. In the first application, the model framework is applied to the Dalälven River basin in Sweden. The efficiency of hydropower operations is found to depend significantly on the linkage between the representative biannual hydrologic regime and the regime actually realised in a future scenario. The forecasting error decreases when considering periodic hydroclimate fluctuations, such as the dry–wet year variability evident in the runoff in the Dalälven River, which ultimately increases production efficiency by approximately 2% (at its largest), as is shown in scenarios 1 and 2. The corresponding potential hydropower production is found to vary by 80 GWh/year. The reduction in forecasting error when considering biennial periodicity corresponds to a production efficiency improvement of about 0.33% (or 13.2 GWh/year).

Selection of best location for small hydropower plant (SHP) along Chamkhar River, bhutanusing analytical hierarchy process (AHP)

Hydropower development activities have been playing an indispensable role in enhancing Bhutan's economy and driving towards its goal of becoming a self-reliant nation. Hydropower being a renewable source of energy with minimal environmental impacts has always synchronized with Bhutan's strict environmental regulations and policies. Despite having remarkable hydropower potential, it has been able to harness only a fraction of the total potential hydropower production only due to various challenges faced by the hydropower sector. There is a lack of in-house resources and experienced local expertise to carry out the specific assessment. Large-scale hydropower projects not only have high upfront cost and risk but also posing severe threats to the environment of terrestrial and riverine ecosystems. Run-off-river small hydropower plants (SHP) are considered to be most cost-effective and more importantly, they have relatively lesser impacts on the environment. It has been understood that river systems in Bhutan have numerous potential sites for SHPs despite facing a challenge in the selection of a suitable location. Hydropower development is a multi-dimensional approach that pivots on various factors and requires a multi-criteria decision analysis (MCDA). This study focuses on criteria prioritization of seven different criteria of locating an SHP along Chamkharriver that has been notable of its potentiality. The analytical hierarchy process (AHP) of MCDA is the most suitable method for selecting the most feasible locations of a hydropower plant in this study. From the total of ten potential sites that have been considered feasible through technical studies, eventually, seven were taken for further suitable analysis. Hence, the five quantitative and two qualitative criteria were used to scale down to the most suitable location using the AHP method. This paper's model resulted that among the criteria, the sanctuary buffer distance (environmental aspect) to be a top priority criterion, followed by heritage (social aspect) and the next was the project cost (economic aspect).

An overview of the hydropower production potential in Bangladesh to meet the energy requirements

Current environmental catastrophes generating from fossil fuel power generation has attracted the attention of energy planners to look for sustainable energy sources. Hydropower is one of the oldest energy sources that have been utilized all over the world to generate electricity, especially in remote areas. Being one of the most densely populated countries, the majority of power demand is fulfilled from fossil fuel. Despite having lots of rivers, Bangladesh has not explored its true potential. So, this paper presents a comprehensive review of the current hydropower potential in Bangladesh. Locations having hydropower potential is evaluated. Different technologies used for hydropower generation have been reviewed. Moreover, global hydropower potential has also been discussed in this study. Based on the economic and environmental study, it is found that small scale hydropower is most feasible in Bangladesh to provide sustainable energy. With a reasonable flow rate, 232 rivers of Bangladesh can be utilized small scale hydropower generation as well as ensuring energy security for remote people. The current study is believed to provide useful information in advancing the generation of hydropower based electricity in Bangladesh.

Alterations in Canadian Hydropower Production Potential Due to Continuation of Historical Trends in Climate Variables

The vitality, timing, and magnitude of hydropower production is driven by streamflow, which is determined by climate variables, in particular precipitation and temperature. Accordingly, changes in climate characteristics can cause alterations in hydropower production potential. This delineates a critical energy security concern, especially in places such as Canada, where recent changes in climate are substantial and hydropower production is important for both domestic use and exportation. Current Canadian assessments, however, are limited as they mainly focus on a small number of power plants across the country. In addition, they implement scenario-led top-down impact assessments that are subject to large uncertainties in climate, hydrological, and energy models. To avoid these limitations, we propose a bottom-up impact assessment based on the historical information on climatic trends and causal links between climate variables and hydropower production across political jurisdictions. Using this framework, we estimate expected monthly gain/loss in regional hydropower production potential under the continuation of historical climate trends. Our findings show that Canada’s production potential is expected to increase, although the net gain/loss is subject to significant variations across different regions. Our results suggest increasing potential in Yukon, Ontario, and Quebec but decreasing production in the North Western Territories and Nunavut, British Columbia, and Alberta.

Probabilistic Projections of Annual Runoff and Potential Hydropower Production in Finland

Exceedance probability of a potential hydropower production was evaluated for 12 river basins located in Finland. The exceedance probability curves of the potential hydropower production were assessed from the probabilistic projections of annual runoff rate. The exceedance probability curves of the ARR are constructed within the Pearson type 3 distributions from simulated parameters, i.e. mean values, coefficient of variation and coefficient of skewness. In our case study, these parameters were simulated from the mean values of annual precipitation rate calculated from outputs of two climate models under three Representative Concentration Pathway's climate scenarios. The future changes in the potential hydropower production for the selected river basins were evaluated on the assumption that a potential hydropower production is linearly related to ARR in all range of exceedance probabilities.

Climate change and hydrological analysis of Tekeze river basin Ethiopia: implication for potential hydropower production

Abstract Climate change is expected to intensify the hydropower production in East Africa. This research investigates the runoff and energy production in the current and future climate for the Tekeze hydropower plant located in the Tekeze river basin in the northern part of Ethiopia. The rainfall-runoff model HBV and the hydropower simulator nMAG were used to generate runoff and energy production in the current and future climate. A combination of five regional climate models and seven global climate models from the Coordinated Regional Climate Downscaling Experiment were used to generate bias-corrected scenarios for the future climate. The result shows an increase in future runoff which was shown to be due to an increase in precipitation. However, the current operational strategy of the power plant did not utilize the future runoff in an optimal way. Therefore, based on the projected future inflow, we have developed a new reservoir operational strategy to preserve water for power production. As a result, the energy production was increased, and the flood spill from the reservoir reduced. This shows the need to adapt the hydropower production system to the future flow regimes to get the most out of the available water.

Hydropower Production in Future Climate Scenarios; the Case for the Zambezi River

Climate change remains a threat to water resources projects in southern Africa where impacts resulting from changes in climate are projected to be negative and worse than in most other regions of the world. This work presents an assessment of the impacts of climate change on water resources and hydropower production potential in the Zambezi River Basin. Future climate scenarios projected through the five General Circulation Model (GCM) outputs are used as input in the impact assessment. The future projected climate scenarios are downscaled to find local and regional changes, and used in the Hydrologiska Byråns Vattenbalansavdelning (HBV) hydrological model to assess climate change impacts on water resources in the river basin. According to the simulations, air temperature and potential evaporation are projected to increase, while rainfall is projected to decrease. The Zambezi hydropower system is likely to be affected negatively as a result of future climate changes. Increasing air temperature leading to increased evaporation, and reduced rainfall, both contribute to a decrease in resulting river flows and increased reservoir evaporation. Consequently, the decrease in water resources will lead to decreased hydropower production potential, by 9% in 2020s, 18% in 2050s and 28% in 2080s in the hydropower system, for a medium emission scenario, A1B.

Hydropower Production in Future Climate Scenarios: The Case for Kwanza River, Angola

Climate change is altering hydrological processes with varying degrees in various regions of the world and remains a threat to water resources projects in southern Africa. The likely negative impacts of changes in Africa may be worse than in most other regions of the world. This study is an evaluation of the possible impacts of climate change on water resources and hydropower production potential in Kwanza River Basin, Angola. The regional climate data, the basis for future climate scenarios, is used in the hydrological model HBV to assess climate change impacts on water resources in the Kwanza River Basin. Evaluation of changes in hydropower production potential is carried out using an energy model. The simulations show that annual rainfall in 2080 would increase by approximately 16% with increasing inter-annual variability of rainfall and dry season river flow and later onset of the rainy season. The simulation results show that for the Kwanza River Basin the effects as a result of changes in the future climate, in general, will be positive. Consequently, the increase in water resources will lead to increased hydropower production potential in the basin by up to 10%.

A GIS-based assessment of maximum potential hydropower production in La Plata basin under global changes

Population growth, economic development, urbanization, changes in hydrological regimes and land use are the main drivers affecting allocation and exploitation of water resources. The pressure exerted by these global changes on the five countries -Argentina, Bolivia, Brazil, Paraguay and Uruguay- located in La Plata Basin over the last decades has raised the need for assessing trends in future electricity demand and energy production in the basin. The aim of this research is to assess whether (and when) shortage and vulnerabilities in terms of hydropower generation are to be expected in La Plata basin in the next decades. The methodology proposed has focused on two aspects to reach the objectives: 1) assessment of hydropower production and electricity demand in the basin over the last twenty years (1987–2008), in order to establish growing trends for the next thirty years; 2) computation of maximum potential hydropower using the newly developed Arc-GIS based tool VAPIDRO-ASTE. The assessment and calculation have been applied to La Plata River and its main tributaries: Paranaiba, Grande River, Tiete, Paranapanema, Iguaçu, Uruguay, Negro River, Paraguay and Paraná. The first outcomes of this research show that La Plata Basin has high hydropower potential. About 40% of the hydropower potential is already used to produce and supply energy. Out of the remaining 60% potential, about 25% could hardly be exploited because of environmental issues or low cost/benefit ratio. Thus, the estimated residual potential hydropower is about 35% of the maximum potential hydropower calculated.

Surface Mass Balance and Runoff Modeling Using HIRHAM4 RCM at Kangerlussuaq (Søndre Strømfjord), West Greenland, 1950–2080

Abstract A regional atmospheric model, the HIRHAM4 regional climate model (RCM) using boundary conditions from the ECHAM5 atmosphere–ocean general circulation model (AOGCM), was downscaled to a 500-m gridcell increment using SnowModel to simulate 131 yr (1950–2080) of hydrologic cycle evolution in west Greenland’s Kangerlussuaq drainage. Projected changes in the Greenland Ice Sheet (GrIS) surface mass balance (SMB) and runoff are relevant for potential hydropower production and prediction of ecosystem changes in sensitive Kangerlussuaq Fjord systems. Mean annual surface air temperatures and precipitation in the Kangerlussuaq area were simulated to increase by 3.4°C and 95 mm water equivalent (w.eq.), respectively, between 1950 and 2080. The local Kangerlussuaq warming was less than the average warming of 4.8°C simulated for the entire GrIS. The Kangerlussuaq SMB loss increased by an average of 0.3 km3 because of a 0.4 km3 rise in precipitation, 0.1 km3 rise in evaporation and sublimation, and 0.6 km3 gain in runoff (1950–2080). By 2080, the spring runoff season begins approximately three weeks earlier. The average modeled SMB and runoff is approximately −0.1 and 1.2 km3 yr−1, respectively, indicating that ∼10% of the Kangerlussuaq runoff is explained by the GrIS SMB net loss. The cumulative net volume loss (1950–2080) from SMB was 15.9 km3, and runoff was 151.2 km3 w.eq. This runoff volume is expected to have important hydrodynamic and ecological impacts on the stratified salinity in the Kangerlussuaq Fjord and on the transport of freshwater to the ocean.

A runoff map based on numerically simulated precipitation and a projection of future runoff in Iceland / Une carte d'écoulement basée sur la précipitation numériquement simulée et un scénario du futur écoulement en Islande

The runoff of Iceland has been evaluated for the period 1961–1990, and changes in runoff from then to the period 2071–2100 predicted according to a future projection of climate change. The hydrological model WASIM-ETH was used, with meteorological data from the PSU/NCAR MM5 numerical weather model. The evaluation of the effects of climate change on water resources was based on a future climate simulation from the HIRHAM regional climate model with boundary conditions from the HadAM3H global climate model using A2 and B2 emissions scenarios. Future runoff was shown to become much higher in 2071–2100 compared to 1961–1990, predominantly due to increased glacial melt caused by increased temperature. Furthermore, changes in runoff seasonality would be substantial. Thus, according to this projection there could be great changes in hydropower production potential associated with climate change in Iceland.

Regional Climate Scenarios for use in Nordic Water Resources Studies

According to global climate projections, a substantial global climate change will occur during the next decades, under the assumption of continuous anthropogenic climate forcing. Global models, although fundamental in simulating the response of the climate system to anthropogenic forcing are typically geographically too coarse to well represent many regional or local features. In the Nordic region, climate studies are conducted in each of the Nordic countries to prepare regional climate projections with more detail than in global ones. Results so far indicate larger temperature changes in the Nordic region than in the global mean, regional increases and decreases in net precipitation, longer growing season, shorter snow season etc. These in turn affect runoff, snowpack, groundwater, soil frost and moisture, and thus hydropower production potential, flooding risks etc. Regional climate models do not yet fully incorporate hydrology. Water resources studies are carried out off-line using hydrological models. This requires archived meteorological output from climate models. This paper discusses Nordic regional climate scenarios for use in regional water resources studies. Potential end-users of water resources scenarios are the hydropower industry, dam safety instances and planners of other lasting infrastructure exposed to precipitation, river flows and flooding.