Demand response performance and uncertainty: A systematic literature review

The present review has been carried out, resorting to the PRISMA methodology, analyzing 218 published articles. A comprehensive analysis has been conducted regarding the consumer's role in the energy market. Moreover, the methods used to address demand response uncertainty and the strategies used to enhance performance and motivate participation have been reviewed. The authors find that participants will be willing to change their consumption pattern and behavior given that they have a complete awareness of the market environment, seeking the optimal decision. The authors also find that a contextual solution, giving the right signals according to the different behaviors and to the different types of participants in the DR event, can improve the performance of consumers' participation, providing a reliable response. DR is a mean of demand-side management, so both these concepts are addressed in the present paper. Finally, the pathways for future research are discussed.This article is a result of the project RETINA (NORTE-01-0145- FEDER-000062), supported by Norte Portugal Regional Operational Programme (NORTE 2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (ERDF). We also acknowledge the work facilities and equipment provided by GECAD research center (UIDB/00760/2020) to the project team, and grants CEECIND/02887/2017 and SFRH/BD/144200/2019.info:eu-repo/semantics/publishedVersio

Water temperature and fish distribution in the Sabie River system : towards the development of an adaptive management tool.

Thesis (Ph.D.)-University of Natal, Pietermaritzburg, 2003.Water temperatures are a fundamental water quality component, and a key abiotic determinant of fish distribution patterns in rivers. A river 's thermal regime is the product of a multitude of thermal drivers and buffers interacting at different temporal and spatial scales, including, inter alia, air temperatures, flow volumes (including groundwater flows and lateral inputs from tributaries), channel geomorphology and riparian vegetation. "Healthy" river systems are self-sustaining, with adequate thermal variability to maintain biotic diversity. Temporal variability of flow volumes and water temperatures, and how these change along the longitudinal axis of a river, contribute towards a rivers "signature". Rivers that have had their signatures altered through anthropogenic impacts may no longer be sustainable, and require varying levels of management. Successful river management should include a quantification of these signatures , a definition of the "desired" state which management aims to achieve, associated "thresholds" of change or concern, and monitoring programmes. Such an approach requires flexibility and adaptability, as well as appropriate tools being available to natural resource managers. Indices, the utility of which are enhanced when included in predicative modelling systems, are a common means of assessing system variability and change. The degree of confidence placed in such tools depends on the level of fundamental science, and the degree of system understanding, underpinning them. This research contributes to the understanding of the ecological significance . of water temperatures in variable semi-arid river systems, using the Sabie River (Mpumalanga, South Africa) as a case study, and indices derived from biological indicators (Chiloglanis , Pisces: Mochokidae) to quantify the effects of cumulative changes in heat units against a hypothesised critical water temperature threshold. Hourly water temperatures for 20002002 collected at nine sites in the main rivers of the Sabie catchment, together with biannual surveys of relative abundances and community patterns of fish collected using standard electrofishing techniques, were used to provide the basis for a modelling system which aims to provide river managers with a tool for quantifying changes to the thermal regime of the Sabie River. This modelling system consisted of a suite of pragmatic models, including multiple linear regression models for simulating daily maximum water temperatures, and simple cause-and-effect relationships between biological indices (change In condition factor and change in the ratio of relative abundances of two species of Chiloglanis) and annual metrics of time-of-exposure to heat stress. It was concluded that changes in the thermal regimes of the rivers in the Sabie catchment are likely to lead to changes in fish distribution patterns, and a decline in river health. Inherent system variability suggests that management decisions will be made in the face considerable uncertainty. Indirect management of water temperatures may be possible through maintenance of flow volumes and flow variability. However, the most appropriate management approach for maintaining fish diversity within these rivers is to ensure that obstacles to fish migration are minimized, to maximise the ability of river biota to respond to thermal changes, by accessing suitable alternative habitats or refugia. Future research should focus on extending the time series of water temperatures from such river systems, and further understanding the drivers and buffers contributing to the thermal regimes of variable semi-arid river systems in South Africa. Additional testing of the validity of the hypothesized relationships between abiotic processes underpinning biotic patterns should be undertaken

New electric utility management and control systems : proceedings of conference, held in Boxborough, Massachusetts, May 30-June 1, 1979

"This work was supported by the Center for Energy Policy Research and the Electric Power Systems Engineering Laboratory of the Massachusetts Institute of Technology.

Novel processes for smart grid information exchange and knowledge representation using the IEC common information model

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.The IEC Common Information Model (CIM) is of central importance in enabling smart grid interoperability. Its continual development aims to meet the needs of the smart grid for semantic understanding and knowledge representation for a widening domain of resources and processes. With smart grid evolution the importance of information and data management has become an increasingly pressing issue not only because far more data is being generated using modern sensing, control and measuring devices but also because information is now becoming recognised as the ‘integral component’ that facilitates the optimal flexibility required of the smart grid. This thesis looks at the impacts of CIM implementation upon the landscape of smart grid issues and presents research from within National Grid contributing to three key areas in support of further CIM deployment. Taking the issue of Enterprise Information Management first, an information management framework is presented for CIM deployment at National Grid. Following this the development and demonstration of a novel secure cloud computing platform to handle such information is described. Power system application (PSA) models of the grid are partial knowledge representations of a shared reality. To develop the completeness of our understanding of this reality it is necessary to combine these representations. The second research contribution reports on a novel methodology for a CIM-based model repository to align PSA representations and provide a knowledge resource for building utility business intelligence of the grid. The third contribution addresses the need for greater integration of information relating to energy storage, an essential aspect of smart energy management. It presents the strategic rationale for integrated energy modeling and a novel extension to the existing CIM standards for modeling grid-scale energy storage. Significantly, this work has already contributed to a larger body of work on modeling Distributed Energy Resources currently under development at the Electric Power Research Institute (EPRI) in the USA.Dr. Martin Bradley on behalf of National Grid Plc. and the Engineering and Physical Sciences Research Council (EPSRC

Developing environmental flows for the Baleh River – hydrological and geomorphological processes in the Baleh catchment prior to damming

Dams have been built in many parts of the world since the earliest human civilizations, but currently there is a significant program of dam building underway in the tropics. Despite general awareness of the likely detrimental impacts of dams, the limited number of empirical tropical studies means that specific effects of dams on these important but imperilled ecosystems are hard to predict. Although the Functional Flows (FFs) concept is now prominent in the scientific and river management literature, it has been applied only to some very specific cases in tropical areas to guide dam operation (e.g. to support periodic flooding of floodplain areas). In these and many other cases, FFs have been applied retrospectively, to design operational flows for existing dams. The work presented in this thesis concerns development of flow recommendations prior to the construction of a large tropical hydropower dam on Baleh River, Sarawak. Specific objectives of the thesis are to: (i) develop a full statistical understanding of the natural hydrological regime of Baleh River, (ii) identify critical habitat forming discharges (those responsible for coarse sediment entrainment and transport) and relations between discharge magnitude and hydraulic habitat heterogeneity, (iii) to assess the impact of the dam and other land use changes on sediment connectivity, and (iv) provide specific recommendations for dam operation to support sediment entrainment and maintenance of habitat heterogeneity, and for management of lake levels to limit changes in connectivity. The work involved analyses of historical data along with a number of empirical field data collection, modelling and remote sensing approaches. For Objective (i), a 51-year hydrological and hydro-climatological dataset was analysed in order to characterise the natural hydrological regime of the Baleh River. The analyses focussed on understanding the frequency, magnitude, duration, and timing of natural high and low flow events. For Objective (ii), HEC-RAS® models were built for 3 study reaches. These models were used to simulate hydraulic conditions across the range of discharges extending from high to low flows. The output from the hydraulic models was combined with information on critical entrainment thresholds of sediment at the 3 reaches in order to understand which flows are capable of entraining sediment. The focus of these analyses was to understand whether the expected hydropower regime is likely to cause sediment entrainment in the way that occurs currently under the natural regime. The analyses also used HEC-RAS® to evaluate hydraulic habitat heterogeneity at low flow conditions. The HEC-RAS® modelling was integrated with Soil and Water Assessment Tool (SWAT® or ArcSWAT®) to understand flow magnitude in the river under different conditions of hydropower operation and rainfall (which would lead to tributaries downstream from the dam discharging high flows to the mainstem Baleh). In addition, the model coupled with the DEMs was used to look at the extent of exposure of gravel bars during low flow conditions. The SedInConnect model was used to understand patterns of sediment connectivity across the Baleh catchment. This model computes the sediment connectivity index (IC). For the modelling, it was necessary to develop DEMs and collate information on landcover in order to calculate topographic roughness and IC. Information on sediment entrainment was used to make recommendations about flows needed to maintain the geomorphic processes (i.e. bedload transport) post-impoundment that occur currently in the natural river. The low flow analyses were used to understand whether hydraulic conditions became more or less heterogeneous at low flows. The hydrological analyses identified 5 distinct classes of high flow event in the Baleh (defined as ‘Event Types’). These types have distinct magnitudes and durations. HEC-RAS® modelling indicated that the smallest of these events led to sediment entrainment of D16 and greater at the study sites, and that larger events resulted in increasing areas of the bed across the study reaches experiencing entrainment. The maximum likely hydropower releases are smaller in discharge magnitude than the smallest of these natural events. The modelling indicated that more or less no sediment entrainment would occur during normal hydropower operations. However, integration of the HEC-RAS® and ArcSWAT® models indicated that when the catchment is wet, tributaries are contributing enough flow to result in sediment entrainment at the study sites that equates to that under some of the higher natural event types. Hydraulic habitat heterogeneity was relatively high during low flows and dropped at moderate and high flows. Moreover, at low flows, gravel bars became exposed at some of the study sites adding to overall habitat heterogeneity. According to the IC models, the impact of historical landcover changes on connectivity between the Baleh and the Rajang has not been pronounced. However, the models predicted that future forest clearance and roads will have observable impacts on the connectivity between the Baleh and Rajang. The models indicated that the construction of the dam would result in a significant impact on connectivity, with the effects of impoundment being greater than those of road and landcover changes, leading to a large portion of the Baleh catchment being almost completely disconnected from the Rajang. The operation of the dam will affect IC upstream of the dam due to the changes in connectivity caused by different lake levels. The HEC-RAS® modelling suggested that over time, in the absence of significant bed entrainment and transport of material, the bed could be expected to become progressively armoured and coarser, as seen in dammed rivers worldwide. However, the modelling also indicated that when the catchment is wet and downstream tributaries are contributing much additional water, flows in the Baleh will greatly exceed turbine releases and appreciable entrainment of bed material can be expected. Recommendations for geomorphic functional flows are made on the basis of these findings. Recommendations are to ensure that hydropower releases using the maximum number of turbines are made during times when the catchment is already wet, to ensure entrainment of bed sediment. Based on analyses of the natural regime, the recommendations include suggestions for timing and duration of such releases. They should last around 20 days, occurring 8 to 15 times per year, predominantly during the wet season. Low flow recommendations were made to occasionally allow dam releases to drop to 1 to 3 turbines to mimic natural low flow events. The recommendation for these events was to allow flow to drop to the natural respective monthly baseflows; these flows should last around 3 days with a frequency of at least 3 times per month during the wet season, and 2 times per month during the dry season. The dam will disconnect a major part of the Baleh catchment from the Rajang. The modelling suggested that the effects of the dam on connectivity will swamp the effects of landcover change and road construction on connectivity. Nevertheless, localised impacts of the road were predicted by the model, with an increase in connectivity on the upslope areas. It is recommended that measures to mitigate this are implemented as part of road construction and management. The model suggested that careful management of lake levels could be used to reduce the impact of the dam on connectivity in the upper part of the basin. The study of functional flows presented in this thesis is of growing importance for sustainable catchment management, particularly in Southeast Asia, where rapid dam construction and vulnerability to the impacts of climate change are prevalent. It is one of few studies globally that has explicitly considered fluvial processes when developing functional flow recommendations. It is also novel in integrating reach scale HEC-RAS® models with catchment scale SWAT® models to help in the design of functional flow recommendations. As far as the author is aware, it is the only study globally to have used the SedInConnect model to understand the combined and interactive effects of damming, landcover change and road construction on structural connectivity at a catchment scale. These approaches can be applied to large rivers in Southeast Asia and other Global South regions, aiding sustainable catchment and water management. It is one of few functional flow studies to have been undertaken before dam closure, allowing us to implement functional recommendations in advance of construction, rather than retrofitting them to a river that has been regulated for some time. It is recommended that a program of monitoring is implemented in the Baleh in order to understand how the river changes in response to impoundment and the success of flow recommendations for maintaining sediment dynamics and habitat heterogeneity. This monitoring will provide the basis for adaptive management

Wind Power

This book is the result of inspirations and contributions from many researchers of different fields. A wide verity of research results are merged together to make this book useful for students and researchers who will take contribution for further development of the existing technology. I hope you will enjoy the book, so that my effort to bringing it together for you will be successful. In my capacity, as the Editor of this book, I would like to thanks and appreciate the chapter authors, who ensured the quality of the material as well as submitting their best works. Most of the results presented in to the book have already been published on international journals and appreciated in many international conferences

Developing environmental flows for the Baleh River – hydrological and geomorphological processes in the Baleh catchment prior to damming

Dams have been built in many parts of the world since the earliest human civilizations, but currently there is a significant program of dam building underway in the tropics. Despite general awareness of the likely detrimental impacts of dams, the limited number of empirical tropical studies means that specific effects of dams on these important but imperilled ecosystems are hard to predict. Although the Functional Flows (FFs) concept is now prominent in the scientific and river management literature, it has been applied only to some very specific cases in tropical areas to guide dam operation (e.g. to support periodic flooding of floodplain areas). In these and many other cases, FFs have been applied retrospectively, to design operational flows for existing dams. The work presented in this thesis concerns development of flow recommendations prior to the construction of a large tropical hydropower dam on Baleh River, Sarawak. Specific objectives of the thesis are to: (i) develop a full statistical understanding of the natural hydrological regime of Baleh River, (ii) identify critical habitat forming discharges (those responsible for coarse sediment entrainment and transport) and relations between discharge magnitude and hydraulic habitat heterogeneity, (iii) to assess the impact of the dam and other land use changes on sediment connectivity, and (iv) provide specific recommendations for dam operation to support sediment entrainment and maintenance of habitat heterogeneity, and for management of lake levels to limit changes in connectivity. The work involved analyses of historical data along with a number of empirical field data collection, modelling and remote sensing approaches. For Objective (i), a 51-year hydrological and hydro-climatological dataset was analysed in order to characterise the natural hydrological regime of the Baleh River. The analyses focussed on understanding the frequency, magnitude, duration, and timing of natural high and low flow events. For Objective (ii), HEC-RAS® models were built for 3 study reaches. These models were used to simulate hydraulic conditions across the range of discharges extending from high to low flows. The output from the hydraulic models was combined with information on critical entrainment thresholds of sediment at the 3 reaches in order to understand which flows are capable of entraining sediment. The focus of these analyses was to understand whether the expected hydropower regime is likely to cause sediment entrainment in the way that occurs currently under the natural regime. The analyses also used HEC-RAS® to evaluate hydraulic habitat heterogeneity at low flow conditions. The HEC-RAS® modelling was integrated with Soil and Water Assessment Tool (SWAT® or ArcSWAT®) to understand flow magnitude in the river under different conditions of hydropower operation and rainfall (which would lead to tributaries downstream from the dam discharging high flows to the mainstem Baleh). In addition, the model coupled with the DEMs was used to look at the extent of exposure of gravel bars during low flow conditions. The SedInConnect model was used to understand patterns of sediment connectivity across the Baleh catchment. This model computes the sediment connectivity index (IC). For the modelling, it was necessary to develop DEMs and collate information on landcover in order to calculate topographic roughness and IC. Information on sediment entrainment was used to make recommendations about flows needed to maintain the geomorphic processes (i.e. bedload transport) post-impoundment that occur currently in the natural river. The low flow analyses were used to understand whether hydraulic conditions became more or less heterogeneous at low flows. The hydrological analyses identified 5 distinct classes of high flow event in the Baleh (defined as ‘Event Types’). These types have distinct magnitudes and durations. HEC-RAS® modelling indicated that the smallest of these events led to sediment entrainment of D16 and greater at the study sites, and that larger events resulted in increasing areas of the bed across the study reaches experiencing entrainment. The maximum likely hydropower releases are smaller in discharge magnitude than the smallest of these natural events. The modelling indicated that more or less no sediment entrainment would occur during normal hydropower operations. However, integration of the HEC-RAS® and ArcSWAT® models indicated that when the catchment is wet, tributaries are contributing enough flow to result in sediment entrainment at the study sites that equates to that under some of the higher natural event types. Hydraulic habitat heterogeneity was relatively high during low flows and dropped at moderate and high flows. Moreover, at low flows, gravel bars became exposed at some of the study sites adding to overall habitat heterogeneity. According to the IC models, the impact of historical landcover changes on connectivity between the Baleh and the Rajang has not been pronounced. However, the models predicted that future forest clearance and roads will have observable impacts on the connectivity between the Baleh and Rajang. The models indicated that the construction of the dam would result in a significant impact on connectivity, with the effects of impoundment being greater than those of road and landcover changes, leading to a large portion of the Baleh catchment being almost completely disconnected from the Rajang. The operation of the dam will affect IC upstream of the dam due to the changes in connectivity caused by different lake levels. The HEC-RAS® modelling suggested that over time, in the absence of significant bed entrainment and transport of material, the bed could be expected to become progressively armoured and coarser, as seen in dammed rivers worldwide. However, the modelling also indicated that when the catchment is wet and downstream tributaries are contributing much additional water, flows in the Baleh will greatly exceed turbine releases and appreciable entrainment of bed material can be expected. Recommendations for geomorphic functional flows are made on the basis of these findings. Recommendations are to ensure that hydropower releases using the maximum number of turbines are made during times when the catchment is already wet, to ensure entrainment of bed sediment. Based on analyses of the natural regime, the recommendations include suggestions for timing and duration of such releases. They should last around 20 days, occurring 8 to 15 times per year, predominantly during the wet season. Low flow recommendations were made to occasionally allow dam releases to drop to 1 to 3 turbines to mimic natural low flow events. The recommendation for these events was to allow flow to drop to the natural respective monthly baseflows; these flows should last around 3 days with a frequency of at least 3 times per month during the wet season, and 2 times per month during the dry season. The dam will disconnect a major part of the Baleh catchment from the Rajang. The modelling suggested that the effects of the dam on connectivity will swamp the effects of landcover change and road construction on connectivity. Nevertheless, localised impacts of the road were predicted by the model, with an increase in connectivity on the upslope areas. It is recommended that measures to mitigate this are implemented as part of road construction and management. The model suggested that careful management of lake levels could be used to reduce the impact of the dam on connectivity in the upper part of the basin. The study of functional flows presented in this thesis is of growing importance for sustainable catchment management, particularly in Southeast Asia, where rapid dam construction and vulnerability to the impacts of climate change are prevalent. It is one of few studies globally that has explicitly considered fluvial processes when developing functional flow recommendations. It is also novel in integrating reach scale HEC-RAS® models with catchment scale SWAT® models to help in the design of functional flow recommendations. As far as the author is aware, it is the only study globally to have used the SedInConnect model to understand the combined and interactive effects of damming, landcover change and road construction on structural connectivity at a catchment scale. These approaches can be applied to large rivers in Southeast Asia and other Global South regions, aiding sustainable catchment and water management. It is one of few functional flow studies to have been undertaken before dam closure, allowing us to implement functional recommendations in advance of construction, rather than retrofitting them to a river that has been regulated for some time. It is recommended that a program of monitoring is implemented in the Baleh in order to understand how the river changes in response to impoundment and the success of flow recommendations for maintaining sediment dynamics and habitat heterogeneity. This monitoring will provide the basis for adaptive management

Ecological effects of flow and temperature regimes on fish communities in temperate rivers

Les organismes aquatiques sont adaptés à une grande variabilité hydrique et thermique des rivières. Malgré ceci, la régulation des eaux suscite des changements aux débits qui peuvent provoquer des impacts négatifs sur la biodiversité et les processus écologiques en rivière. Celle-ci peut aussi causer des modifications au niveau des régimes thermiques et des caractéristiques de l’habitat du poisson. Des données environnementales et biologiques décrivant l’habitat du poisson existent, mais elles sont incomplètes pour plusieurs rivières au Canada et de faible qualité, limitant les relations quantitatives débit-température-poissons à un petit nombre de rivières ou à une région étudiée. La recherche menée dans le cadre de mon doctorat concerne les impacts de la génération d'hydroélectricité sur les rivières; soit les changements aux régimes hydriques et thermiques reliés à la régulation des eaux sur la variation des communautés ichtyologiques qui habitent les rivières régulées et naturelles au Canada. Suite à une comparaison d’échantillonnage de pêche, une méthode constante pour obtenir des bons estimés de poisson (richesse, densité et biomasse des espèces) a été établie pour évaluer la structure de la communauté de poissons pour l’ensemble des rivières ciblées par l’étude. Afin de mieux comprendre ces changements environnementaux, les principales composantes décrivant ces régimes ont été identifiées et l’altération des régimes hydriques pour certaines rivières régulées a été quantifiée. Ces résultats ont servi à établir la relation significative entre le degré de changement biotique et le degré de changement hydrique pour illustrer les différences entre les régimes de régulation. Pour faire un complément aux indices biotiques déjà calculés pour l’ensemble des communautés de poissons (diversité, densité et biomasse des espèces par rivière), les différences au niveau des guildes de poissons ont été quantifiées pour expliquer les divers effets écologiques dus aux changements de régimes hydriques et thermiques provenant de la gestion des barrages. Ces derniers résultats servent à prédire pour quels traits écologiques ou groupes d’espèces de poissons les composantes hydriques et thermiques sont importantes. De plus, ces derniers résultats ont servi à mettre en valeur les variables décrivant les régimes thermiques qui ne sont pas toujours inclues dans les études hydro-écologiques. L’ensemble des résultats de cette thèse ont des retombées importantes sur la gestion des rivières en évaluant, de façon cohérente, l’impact de la régulation des rivières sur les communautés de poissons et en développant des outils de prévision pour la restauration des écosystèmes riverains.Widespread anthropogenic impacts to river ecosystems are currently changing the naturaly variability of flow and temperature regimes, with potentially important repercussions on the stability and function of aquatic communities. Although fish community responses to flow alterations from river regulation have been quantified in the past (e.g. late maturation of salmonid populations due to attenuated flows or stranding of fishes from down-ramping flows), the scarcity of high quality, long-term data, especially in Canadian rivers, has limited our understanding of the effect this has had on other environmental drivers and fish community structure across this heterogenous landscape. Using extensive field surveying across unregulated and regulated rivers in Alberta, Ontario, Québec, and New Brunswick coupled with data from national, provincial, and private flow and water temperature gauge networks, I showed the effects of flow and thermal regimes on fish diversity, density, biomass, and different types of ecological guilds. I also examined the extent to which different regulation practices have modulated the response of riverine fish to the combined effect of changes to flow and thermal regimes. To first establish a methodology for quantifying fish community structure across rivers, I generated reliable site-specific species richness, density, and biomass metrics that combined measures from two commonly used surveying methods. To then quantify the response of these fish community metrics to river regulation, I defined daily and hourly flow indices based on river flow conditions, developed hydrologic regime variables that described dominant patterns of flow variation, and calculated flow alterations based on the difference in multivariate space of these hydrologic regime variables for regulated rivers from reference flow conditions. By applying this same approach to fish community metrics, I identified a significant positive relationship between biotic and flow alterations and showed a separation between the two most distinct flow regulation types, run-of-river (ROR) and hydro-peaking. To tease apart the relative importance of each environmental driver for establishing fish communities across river regimes, I provided quantitive thermal indices based on river water temperatures and developed thermal variables akin to those described for flow regimes. To evaluate whether quantitative fish guild estimates, rather than total river biomass or density estimates, would respond more strongly to river thermal regimes, I compared the response of different types of fish guilds to flow and thermal regimes across rivers, including those subjected to river regulation. All fish guild models performed better relative to studying total river estimates, confirming the use of trait-environmental relationships for studying fish community responses across rivers. I also found that integrating thermal regimes in hydro-ecological studies is critical in predicting fish guild responses across rivers. Collectively, these findings have important repercussions for river management, as they provide comprehensive assessments of the environmental variables driving fish community responses, inform the potential range of ecological consequences of anthropogenic alterations on natural flow regimes, and contribute to establishing more transferable predictions for restoring impacted rivers. More broadly, the thesis results are important given future global climate warming, its synergistic effects with other anthropogenic stressors, and ongoing scarcity for water and energy sources