The future of Swiss run-of-river hydropower production: climate change, environmental flow requirements and technical production potential

Run-of-river (RoR) hydropower is essential in Alpine energy production and highly sensitive to climate change, due to no or limited water storage capacity. Here, we estimate climate change impact on 21 RoR plants in Switzerland, where 60% of the annual electricity is produced by hydropower (30% by RoR). This is one of the first comprehensive, simulation-based studies on climate change impacts on Alpine RoR production, including effects of environmental flow requirements and technical production potential. We simulate three future periods under three emission scenarios (RCP2.6, RCP4.5, RCP8.5). The results show an increase of winter and a decrease of summer production, which in conjunction leads to an annual decrease. The simulated impacts strongly depend on the elevation and the plant-specific characteristics. A key result is that the climate induced reduction is not linearly related to the underlying streamflow reduction, but is modulated by environmental flow requirements, the design discharge and streamflow projections. Stronger impacts are expected if climate change affects streamflow in the range that is usable for production. This result is transferable to RoR production in similar settings and should be considered in future assessments. Future work could in particular focus on further technical optimisation potential, considering detailed operational data.

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Climate change impacts on maritime mountain snowpack in the Oregon Cascades

Hydrology and Earth System Sciences Discussions ◽

10.5194/hessd-9-13037-2012 ◽

2012 ◽

Vol 9 (11) ◽

pp. 13037-13081 ◽

Cited By ~ 5

Author(s):

E. Sproles ◽

A. Nolin ◽

K. Rittger ◽

T. Painter

Keyword(s):

Climate Change ◽

Snow Water Equivalent ◽

Regional Scale ◽

Climate Change Impacts ◽

Snow Accumulation ◽

Distributed Model ◽

Modeling Framework ◽

Highly Sensitive ◽

Snow Cover Extent ◽

Snow Water

Abstract. Globally maritime snow comprises 10% of seasonal snow and is considered highly sensitive to changes in temperature. This study investigates the effect of climate change on maritime mountain snowpack in the McKenzie River Basin (MRB) in the Cascades Mountains of Oregon, USA. Melt water from the MRB's snowpack provides critical water supply for agriculture, ecosystems, and municipalities throughout the region especially in summer when water demand is high. Because maritime snow commonly falls at temperatures close to 0 °C, accumulation of snow versus rainfall is highly sensitive to temperature increases. Analyses of current climate and projected climate change impacts show rising temperatures in the region. To better understand the sensitivity of snow accumulation to increased temperatures, we modeled the spatial distribution of snow water equivalent (SWE) in the MRB for the period of 1989–2009 with the SnowModel spatially distributed model. Simulations were evaluated using point-based measurements of SWE, precipitation, and temperature that showed Nash-Sutcliffe Efficiency coefficients of 0.83, 0.97, and 0.80, respectively. Spatial accuracy was shown to be 82% using snow cover extent from the Landsat Thematic Mapper. The validated model was used to evaluate the sensitivity of snowpack to projected temperature increases and variability in precipitation, and how changes were expressed in the spatial and temporal distribution of SWE. Results show that a 2 °C increase in temperature would shift peak snowpack 12 days earlier and decrease basin-wide volumetric snow water storage by 56%. Snowpack between the elevations of 1000 and 1800 m is the most sensitive to increases in temperature. Upper elevations were also affected, but to a lesser degree. Temperature increases are the primary driver of diminished snowpack accumulation, however variability in precipitation produce discernible changes in the timing and volumetric storage of snowpack. This regional scale study serves as a case study, providing a modeling framework to better understand the impacts of climate change in similar maritime regions of the world.

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Integrated Modeling of Water Supply and Demand Under Climate Change Impacts and Management Options in Tributary Basin of Tonle Sap Lake, Cambodia

Water ◽

10.3390/w12092462 ◽

2020 ◽

Vol 12 (9) ◽

pp. 2462

Author(s):

Tharo Touch ◽

Chantha Oeurng ◽

Yanan Jiang ◽

Ali Mokhtar

Keyword(s):

Climate Change ◽

Water Resources ◽

Water Supply ◽

Supply And Demand ◽

Climate Change Impacts ◽

Environmental Flow ◽

Integrated Modeling ◽

Supply Management ◽

Management Options ◽

The Future

An integrated modeling approach analyzing water demand and supply balances under management options in a river basin is essential for the management and adaptive measures of water resources in the future. This study evaluated the impacts of climate change on the hydrological regime by predicting the change in both monthly and seasonal streamflow, and identified water supply and demand relations under supply management options and environmental flow maintenance. To reach a better understanding of the consequences of possible climate change scenarios and adaptive management options on water supply, an integrated modeling approach was conducted by using the soil and water assessment tool (SWAT) and water evaluation and planning model (WEAP). Future scenarios were developed for the future period: 2060s (2051–2070), using an ensemble of three general circulation model (GCM) simulations: GFDL-CM3, GISS-E2-R-CC, and IPSL-CM5A-MR, driven by the climate projection for representative concentration pathways (RCPs): 6.0 (medium emission scenario). The results indicated that, firstly, the future streamflow will decrease, resulting in a decline of future water availability. Secondly, water supply under natural flow conditions would support 46,167 ha of irrigation schemes and the water shortages will be more noticeable when environmental flow maintenance was considered. The study concludes that reservoir construction would be necessary for agriculture mitigation and adaptation to climate change. Furthermore, the water resources management options considering both supply and demand management are more effective and useful than supply management only, particularly in dealing with climate change impacts.

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Future Alpine hydropower production: impacts of climate change, residual flow and technical optimization on Run-of-River power plants in Switzerland

10.5194/egusphere-egu2020-9372 ◽

2020 ◽

Author(s):

Tobias Wechsler ◽

Manfred Stähli ◽

Massimiliano Zappa ◽

Klaus Jorde ◽

Bettina Schaefli

Keyword(s):

Climate Change ◽

Power Plants ◽

Climate Change Mitigation ◽

Annual Production ◽

Reference Period ◽

Residual Flow ◽

Hydropower Production ◽

Production Increase ◽

Change Mitigation ◽

Run Of River

In Switzerland, around 57 % of electricity is generated by hydropower (HP), whereof around 25 % are produced by run-of-river (RoR) power plants. This share is expected to only slightly increase in the context of the Swiss energy strategy 2050, by about 10 % (in total 38&#8217;600 GWh/a). Nevertheless, growing energy demand coupled to growing ecological awareness is catapulting hydropower into a position of great expectation and responsibility. In this context, the present research project proposes to assess the impact of climate change and of evolving environmental flow constraints on RoR production in Switzerland. The obtained results are compared to the production increase that could potentially be achieved by technical optimization.To assess climate change impacts, daily runoff until the end of the century was calculated with the hydrological model PREVAH, using a total of 26 climate model chains in transient simulation from the new Swiss Climate Change Scenarios CH2018, corresponding to the two different CO2 emission scenarios RCP2.6 and RCP8.5. Changes in HP generation under climate change are estimated for 11 RoR power plants based on differences in the flow duration curves (FDCs) between the reference period (1981-2010) and the future periods (2045&#8211;2074 and 2070&#8211;2099), assuming unchanged installed machinery and residual water flow requirements.The changes in HP production from RoR power plants are due to changes in precipitation, temperature and evaporation, which in turn have a strong impact on the dominant hydrological processes (snow accumulation and melt, glacier melt and runoff production), and show important spatial and temporal differences. By mid-century (2045&#8211;2074) and under concerted mitigation efforts (RCP2.6), annual production will remain roughly the same as during the reference period. Production will decrease slightly (about -3 %) without climate change mitigation (RCP8.5). Exceptions are power plants which are strongly influenced by melt processes. Due to reduced snowfall and increased winter precipitation and ensuing higher winter streamflows, winter production will increase at almost all RoR power plants considered in this study by mid-century, by about 5 % on average.By the end of the century (2070&#8211;2099), a slight decline of the annual production (-1.5 %) is to be expected under RCP2.6. Without climate change mitigation (RCP8.5), annual production will fall further (-7 %). Winter production will increase at virtually all studied RoR power plants. Depending on the emissions scenario, the average winter production increase will be between 5 % (RCP2.6) and 10 % (RCP8.5). However, this increase in winter production will not be sufficient to prevent annual production decline.These climate change induced reductions of annual HP can be put into context by comparing the production losses that result from residual flow requirements. For the RoR power plants under consideration, compliance with legal constraints on residual flow rates, compared to no residual flow, means a difference of less than 4 %. We will discuss in detail the relevance of ecological constraints and of technical and thereby give a complete picture of emerging challenges and opportunities for Alpine hydropower production under climate and societal change.&#160;

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Investigation of climate change impacts on hydropower generation: the case of a run-of-river small hydropower plant in North Western Greece

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/899/1/012026 ◽

2021 ◽

Vol 899 (1) ◽

pp. 012026

Author(s):

C Skoulikaris ◽

K Kasimis

Keyword(s):

Climate Change ◽

Climate Models ◽

Regional Climate ◽

Climate Change Impacts ◽

Regional Climate Models ◽

Hydropower Plant ◽

Small Hydropower ◽

Hydropower Plants ◽

Run Of River

Abstract Services and uses arising from surface water‘s availability, such as hydropower production, are bound to be affected by climate change. The object of the research is to evaluate climate change impacts on energy generation produced by run-of-river small hydropower plants with the use of future river discharges derived from two up-to-date Regional Climate Models. For doing so, the hydropower simulation model HEC-ResSim, calibrated and validated over real power data, was used to simulate the generated energy in the two future periods of 2031-2060 and 2071-2100. The future river discharges in the case study area are derived from the hydrological model E-HYPE that uses as forcing the climatic variables of the CSC-REMO2009-MPI-ESM-LR and KNMI-RACMO22E-EC-EARTH climate models under two Representative Concentration Pathways, namely RCP4.5 and RCP8.5. The research outputs demonstrate a decrease of the generated energy varying from 2.86% to 25.79% in comparison to the reference period of 1971-2000. However, in most of the simulated scenarios the decrease is less than 10.0%, while increased energy production is projected for one of the scenarios. Overall, it can be concluded that the case study run-of-river small hydropower plant will be marginally affected by climate change when the decrease of the relevant river discharges is up to 10-15%.

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Hydropower Potential of Run of River Schemes in the Himalayas under Climate Change: A Case Study in the Dudh Koshi Basin of Nepal

Water ◽

10.3390/w12092625 ◽

2020 ◽

Vol 12 (9) ◽

pp. 2625

Author(s):

Daniele Bocchiola ◽

Mattia Manara ◽

Riccardo Mereu

Keyword(s):

Climate Change ◽

General Circulation ◽

Fossil Fuels ◽

General Circulation Models ◽

Energy Deficit ◽

Intergovernmental Panel ◽

Mountain Areas ◽

Hydropower Potential ◽

Hydropower Production ◽

Run Of River

In spite of the very large hydropower potential given from the melting snow and ice of Himalayas, Nepal’s population has little hydropower production. The high use of fossil fuels and biomasses results in measurable air pollution, even in the mountain areas. Hydropower planning and implementation, in the face of the changing climate, is therefore paramount important. We focus here on Nepal, and particularly on the Dudh Koshi river basin, with a population of ca. 170,000 people, within an area with large potential for hydropower production. Our main objectives are to (i) preliminarily design a local hydropower grid based on a distributed run of river ROR scheme, and (ii) verify the resilience of the grid against modified hydrology under perspective climate change, until the end of the century. To do so, we set up and tune the Poli-Hydro semi-distributed glacio-hydrological model, mimicking the complex hydrology of the area. We then modify a state of the art algorithm to develop and exploit a heuristic, resource-demand based model, called Poli-ROR. We use Poli-ROR to assess the (optimal) distribution of a number of ROR hydropower stations along the river network, and the structure of the local mini-grids. We then use downscaled outputs from three general circulation models GCMs (RCPs 2.6, 4.5, 8.5) from the Intergovernmental Panel on Climate Change IPCC AR5, to assess the performance of the system under future modified hydrological conditions. We find that our proposed method is efficient in shaping ROR systems, with the target of the largest possible coverage (93%), and of the least price (0.068 € kWh−1 on average). We demonstrate also that under the projected hydrological regimes until 2100, worse conditions than now may occur, especially for plants with small drainage areas. Days with energy shortage may reach up to nf = 38 per year on average (against nf = 24 now), while the maximum daily energy deficit may reach as high as edef% = 40% (against edef% = 20% now). We demonstrate that our originally proposed method for ROR grid design may represent a major contribution towards the proper development of distributed hydropower production in the area. Our results may contribute to improve energy supply, and living conditions within the Dudh Koshi river. It is likely that our approach may be applied in Nepal generally. Impending climate change may require adaptation in time, including the use of other sources which are as clean as possible, to limit pollution. Our Poli-ROR method for grid optimization may be of use for water managers, and scientists with an interest in the design of optimal hydropower schemes in topographically complex catchments.

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Exploratory analyses for the assessment of climate change impacts on the energy production in an Amazon run-of-river hydropower plant

Journal of Hydrology Regional Studies ◽

10.1016/j.ejrh.2015.04.003 ◽

2015 ◽

Vol 4 ◽

pp. 41-59 ◽

Cited By ~ 19

Author(s):

Guilherme Samprogna Mohor ◽

Daniel Andrés Rodriguez ◽

Javier Tomasella ◽

José Lázaro Siqueira Júnior

Keyword(s):

Climate Change ◽

Energy Production ◽

Climate Change Impacts ◽

Hydropower Plant ◽

Run Of River

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Climate change and the Antarctic marine ecosystem: an essay on management implications

Antarctic Science ◽

10.1017/s0954102010000222 ◽

2010 ◽

Vol 22 (4) ◽

pp. 387-398 ◽

Cited By ~ 29

Author(s):

P.N. Trathan ◽

D. Agnew

Keyword(s):

Climate Change ◽

Current Knowledge ◽

Marine Ecosystem ◽

Climate Change Impacts ◽

Shared Responsibility ◽

Marine Communities ◽

Relative Risks ◽

Antarctic Marine ◽

Future Work ◽

The Antarctic

AbstractIn this paper we review evidence for, and anticipated consequences of, climate change in Antarctic marine communities, examining the potential impacts on invertebrates and vertebrates alike and exploring plausible outcomes for species, with examples principally from the Antarctic literature. We suggest that industries with the greatest potential to aggravate climate change impacts on marine communities are marine capture fisheries. In the Southern Ocean, harvesting is governed under the Convention for the Conservation of Antarctic Marine Living Resources (CCAMLR). CCAMLR espouses an ecological management framework and so has the capacity to mitigate harvesting impacts such that they do not worsen impacts from climate change. We discuss some of the implications of climate change and advocate that CCAMLR address certain key issues if it is to fulfil its international obligations. It will be essential for CCAMLR to determine relative risks (uncertainties), impacts and timescales, of various processes consequent on climate change. Such risk assessments should be feasible with current knowledge and should provide a focus for future work. We believe it will be important to prioritize issues that reduce impacts and uncertainties by the greatest degree, and propose that future plans should involve shared responsibility (e.g. with SCAR etc.) for each of the risks described.

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Implications of climate change impacts for the Brazilian electricity mix

Sustentabilidade em Debate ◽

10.18472/sustdeb.v11n3.2020.33998 ◽

2021 ◽

Vol 11 (3) ◽

pp. 122-156

Author(s):

Eveline Vasquez-Arroyo ◽

Dan Abensur Gandelman ◽

Fábio da Silva ◽

Letícia Magalar ◽

Diogo Victor Santos ◽

...

Keyword(s):

Climate Change ◽

Marginal Cost ◽

Climate Models ◽

Climate Change Impacts ◽

Thermoelectric Generation ◽

Hydropower Generation ◽

Electricity System ◽

Highly Sensitive ◽

Electricity Mix ◽

Considerable Impact

Hydropower generation is responsible for supplying most of the electricity in Brazil. Like other renewable sources, water is highly sensitive to meteorological variables, so that climate change may have a considerable impact on it. Therefore, this study aims at assessing climate change impacts on hydropower generation and their consequences for the Brazilian electricity system. Scenario data for specific average global warming levels of 2°C and 4°C from Eta_HadGEM2-ES and Eta_MIROC5 downscaled climate models are used. Outcomes indicate that the electricity system’s adaptive capacity to lower hydropower generation includes a growing share of other renewable and natural gas fired thermoelectric generation, increasing the system’s marginal cost to meet projected demand in 2030. Greenhouse gas emissions are projected to increase in a 2°C scenario, but to decrease in scenarios in which warming reaches 4°C.

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Run-Of-River Small Hydropower Plants as Hydro-Resilience Assets against Climate Change

Sustainability ◽

10.3390/su132414001 ◽

2021 ◽

Vol 13 (24) ◽

pp. 14001

Author(s):

Charalampos Skoulikaris

Keyword(s):

Climate Change ◽

Climate Models ◽

Renewable Energy Sources ◽

Regional Climate ◽

Regional Climate Models ◽

Small Hydropower ◽

Hydropower Plants ◽

Hydropower Production ◽

Run Of River

Renewable energy sources, due to their direct (e.g., wind turbines) or indirect (e.g., hydropower, with precipitation being the generator of runoff) dependence on climatic variables, are foreseen to be affected by climate change. In this research, two run-of-river small hydropower plants (SHPPs) located at different water districts in Greece are being calibrated and validated, in order to be simulated in terms of future power production under climate change conditions. In doing so, future river discharges derived by the forcing of a hydrology model, by three Regional Climate Models under two Representative Concentration Pathways, are used as inputs for the simulation of the SHPPs. The research concludes, by comparing the outputs of short-term (2031–2060) and long-term (2071–2100) future periods to a reference period (1971–2000), that in the case of a significant projected decrease in river discharges (~25–30%), a relevant important decrease in the simulated future power generation is foreseen (~20–25%). On the other hand, in the decline projections of smaller discharges (up to ~15%) the generated energy depends on the intermonthly variations of the river runoff, establishing that runoff decreases in the wet months of the year have much lower impact on the produced energy than those occurring in the dry months. The latter is attributed to the non-existence of reservoirs that control the operation of run-of-river SHPPs; nevertheless, these types of hydropower plants can partially remediate the energy losses, since they are taking advantage of low flows for hydropower production. Hence, run-of-river SHPPs are designated as important hydro-resilience assets against the projected surface water availability decrease due to climate change.

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