http://dx.doi.org/10.1680/ener.2010.163.3.93 The renewable energy route map for Wales outlines am... more http://dx.doi.org/10.1680/ener.2010.163.3.93 The renewable energy route map for Wales outlines ambitious targets for 50% renewables by 2025. The Welsh coast, subject to tidal ranges of the order of 13 m and tidal flows in excess of 3 m/s, is thus in an ideal position to significantly contribute to these targets. Tidal stream energy is an emerging energy sector and a relatively small number of devices are at various stages of development in Wales. However, before such demonstration devices or arrays can be applied at a larger scale, a number of consents and permissions must be obtained to ensure safe and environmentally responsible deployment. This paper describes the multidisciplinary work that has been undertaken on an area of ocean that could be used for the deployment of a tidal stream turbine. The paper aims to put the scientific work undertaken into the context of device deployment in a complex marine environment and to provide an overview of the surveying and modelling required for the deployment of a single demonstration device off the Welsh coast. The Bristol Channel was chosen as a case study because of its high tidal flows and proximity to national grid connections and support infrastructure. This paper provides an overview of the research carried out during the project; the details of each discipline will be provided in individual papers by the respective subject authors.
Abstract
Interest in the marine renewable energy devices, and particularly tidal stream turbines... more Abstract
Interest in the marine renewable energy devices, and particularly tidal stream turbines, has increased significantly over the past decade and several devices such as vertical and horizontal axis turbines and reciprocating hydrofoils are now being designed around the world to harness tidal stream energy. While tidal stream turbines are being developed at a high rate and getting closer to commercialisation, it is important to acquire the right tools to assist planners and environmentalists, not only in finding a right location for the turbines, but also in identifying their potential impacts on the surrounding marine and coastal environment.
In this study, a widely used open source depth integrated 2D hydro-environmental model, namely DIVAST, was modified to simulate the hydro-environmental impacts of the turbines in the coastal environment. The model predictions showed very good agreement with previously published 1D model results. Then, for demonstration purposes, the model was applied to an arbitrary array of tidal stream turbines in the Severn Estuary and Bristol Channel which has the third highest tidal range in the world. The model has shown promising potential in investigating the impacts of the array on water levels, tidal currents and sediment and faecal bacteria levels as well as the generated tidal power, which facilitates investigating the relative far-field impacts of the arrays under various climate change scenarios or different formations of the array.
"Sediment transport as a complicated and important phenomenon has attracted a lot of researchers ... more "Sediment transport as a complicated and important phenomenon has attracted a lot of researchers during the last century; however there are some formulae to evaluate sediment loads in aquatic systems. Most of them still face two major problems: firstly, lack of accuracy and secondly, involvement of many parameters
which makes them more challenging.
Artificial Neural Networks are known as model-free universal function approximators well suited to deal with real life engineering problems including time series predictions and parameter estimation. In this paper, sediment loads are predicted using two different types of multilayer feedforward neural networks, namely Multi-Layer perceptron (MLP) and Radial Basis Function (RBF). The input variables for both structures are
considered to be flow discharge, mean flow depth and width, mean bed material’s diameter and water surface slope and the output is sediment discharge. Some different cases have been studied. The results are promising. It has been also observed that mean square prediction errors for the developed MLP is equal to 0.0063 while the devised RBF networks produces much larger mean square errors, namely 0.01260. This indicates that the MLP- load-predictor outperforms the RBF-predictor."
Tidal renewable energy schemes have a variety of economic and ecological effects. It is therefore... more Tidal renewable energy schemes have a variety of economic and ecological effects. It is therefore necessary to use models that can integrate these effects and sometimes conflicting requirements. An input-output model has been applied to the Severn Barrage, one of the proposed tidal barrages on the Severn Estuary. While this project could produce around 17 TWH per annum of carbon free electricity which is around 5% of the UK electricity demand, diverse impacts on habitats as well as different users of the estuary have to be taken into ...
... Roger A. Falconer, Binliang Lin, Reza Ahmadian and Junqiang Xia Hydro-environmental Research ... more ... Roger A. Falconer, Binliang Lin, Reza Ahmadian and Junqiang Xia Hydro-environmental Research Centre, School of Engineering, Cardiff University, Cardiff, UK Email: FalconerRA@ cf.ac.uk, LinBL@cf.ac.uk, xiaj1@cf.ac.uk and AhmadianR@cf.ac.uk ABSTRACT ...
http://dx.doi.org/10.1680/ener.2010.163.3.93 The renewable energy route map for Wales outlines am... more http://dx.doi.org/10.1680/ener.2010.163.3.93 The renewable energy route map for Wales outlines ambitious targets for 50% renewables by 2025. The Welsh coast, subject to tidal ranges of the order of 13 m and tidal flows in excess of 3 m/s, is thus in an ideal position to significantly contribute to these targets. Tidal stream energy is an emerging energy sector and a relatively small number of devices are at various stages of development in Wales. However, before such demonstration devices or arrays can be applied at a larger scale, a number of consents and permissions must be obtained to ensure safe and environmentally responsible deployment. This paper describes the multidisciplinary work that has been undertaken on an area of ocean that could be used for the deployment of a tidal stream turbine. The paper aims to put the scientific work undertaken into the context of device deployment in a complex marine environment and to provide an overview of the surveying and modelling required for the deployment of a single demonstration device off the Welsh coast. The Bristol Channel was chosen as a case study because of its high tidal flows and proximity to national grid connections and support infrastructure. This paper provides an overview of the research carried out during the project; the details of each discipline will be provided in individual papers by the respective subject authors.
Abstract
Interest in the marine renewable energy devices, and particularly tidal stream turbines... more Abstract
Interest in the marine renewable energy devices, and particularly tidal stream turbines, has increased significantly over the past decade and several devices such as vertical and horizontal axis turbines and reciprocating hydrofoils are now being designed around the world to harness tidal stream energy. While tidal stream turbines are being developed at a high rate and getting closer to commercialisation, it is important to acquire the right tools to assist planners and environmentalists, not only in finding a right location for the turbines, but also in identifying their potential impacts on the surrounding marine and coastal environment.
In this study, a widely used open source depth integrated 2D hydro-environmental model, namely DIVAST, was modified to simulate the hydro-environmental impacts of the turbines in the coastal environment. The model predictions showed very good agreement with previously published 1D model results. Then, for demonstration purposes, the model was applied to an arbitrary array of tidal stream turbines in the Severn Estuary and Bristol Channel which has the third highest tidal range in the world. The model has shown promising potential in investigating the impacts of the array on water levels, tidal currents and sediment and faecal bacteria levels as well as the generated tidal power, which facilitates investigating the relative far-field impacts of the arrays under various climate change scenarios or different formations of the array.
"Sediment transport as a complicated and important phenomenon has attracted a lot of researchers ... more "Sediment transport as a complicated and important phenomenon has attracted a lot of researchers during the last century; however there are some formulae to evaluate sediment loads in aquatic systems. Most of them still face two major problems: firstly, lack of accuracy and secondly, involvement of many parameters
which makes them more challenging.
Artificial Neural Networks are known as model-free universal function approximators well suited to deal with real life engineering problems including time series predictions and parameter estimation. In this paper, sediment loads are predicted using two different types of multilayer feedforward neural networks, namely Multi-Layer perceptron (MLP) and Radial Basis Function (RBF). The input variables for both structures are
considered to be flow discharge, mean flow depth and width, mean bed material’s diameter and water surface slope and the output is sediment discharge. Some different cases have been studied. The results are promising. It has been also observed that mean square prediction errors for the developed MLP is equal to 0.0063 while the devised RBF networks produces much larger mean square errors, namely 0.01260. This indicates that the MLP- load-predictor outperforms the RBF-predictor."
Tidal renewable energy schemes have a variety of economic and ecological effects. It is therefore... more Tidal renewable energy schemes have a variety of economic and ecological effects. It is therefore necessary to use models that can integrate these effects and sometimes conflicting requirements. An input-output model has been applied to the Severn Barrage, one of the proposed tidal barrages on the Severn Estuary. While this project could produce around 17 TWH per annum of carbon free electricity which is around 5% of the UK electricity demand, diverse impacts on habitats as well as different users of the estuary have to be taken into ...
... Roger A. Falconer, Binliang Lin, Reza Ahmadian and Junqiang Xia Hydro-environmental Research ... more ... Roger A. Falconer, Binliang Lin, Reza Ahmadian and Junqiang Xia Hydro-environmental Research Centre, School of Engineering, Cardiff University, Cardiff, UK Email: FalconerRA@ cf.ac.uk, LinBL@cf.ac.uk, xiaj1@cf.ac.uk and AhmadianR@cf.ac.uk ABSTRACT ...
Uploads
Papers by Reza Ahmadian
Interest in the marine renewable energy devices, and particularly tidal stream turbines, has increased significantly over the past decade and several devices such as vertical and horizontal axis turbines and reciprocating hydrofoils are now being designed around the world to harness tidal stream energy. While tidal stream turbines are being developed at a high rate and getting closer to commercialisation, it is important to acquire the right tools to assist planners and environmentalists, not only in finding a right location for the turbines, but also in identifying their potential impacts on the surrounding marine and coastal environment.
In this study, a widely used open source depth integrated 2D hydro-environmental model, namely DIVAST, was modified to simulate the hydro-environmental impacts of the turbines in the coastal environment. The model predictions showed very good agreement with previously published 1D model results. Then, for demonstration purposes, the model was applied to an arbitrary array of tidal stream turbines in the Severn Estuary and Bristol Channel which has the third highest tidal range in the world. The model has shown promising potential in investigating the impacts of the array on water levels, tidal currents and sediment and faecal bacteria levels as well as the generated tidal power, which facilitates investigating the relative far-field impacts of the arrays under various climate change scenarios or different formations of the array.
which makes them more challenging.
Artificial Neural Networks are known as model-free universal function approximators well suited to deal with real life engineering problems including time series predictions and parameter estimation. In this paper, sediment loads are predicted using two different types of multilayer feedforward neural networks, namely Multi-Layer perceptron (MLP) and Radial Basis Function (RBF). The input variables for both structures are
considered to be flow discharge, mean flow depth and width, mean bed material’s diameter and water surface slope and the output is sediment discharge. Some different cases have been studied. The results are promising. It has been also observed that mean square prediction errors for the developed MLP is equal to 0.0063 while the devised RBF networks produces much larger mean square errors, namely 0.01260. This indicates that the MLP- load-predictor outperforms the RBF-predictor."
Interest in the marine renewable energy devices, and particularly tidal stream turbines, has increased significantly over the past decade and several devices such as vertical and horizontal axis turbines and reciprocating hydrofoils are now being designed around the world to harness tidal stream energy. While tidal stream turbines are being developed at a high rate and getting closer to commercialisation, it is important to acquire the right tools to assist planners and environmentalists, not only in finding a right location for the turbines, but also in identifying their potential impacts on the surrounding marine and coastal environment.
In this study, a widely used open source depth integrated 2D hydro-environmental model, namely DIVAST, was modified to simulate the hydro-environmental impacts of the turbines in the coastal environment. The model predictions showed very good agreement with previously published 1D model results. Then, for demonstration purposes, the model was applied to an arbitrary array of tidal stream turbines in the Severn Estuary and Bristol Channel which has the third highest tidal range in the world. The model has shown promising potential in investigating the impacts of the array on water levels, tidal currents and sediment and faecal bacteria levels as well as the generated tidal power, which facilitates investigating the relative far-field impacts of the arrays under various climate change scenarios or different formations of the array.
which makes them more challenging.
Artificial Neural Networks are known as model-free universal function approximators well suited to deal with real life engineering problems including time series predictions and parameter estimation. In this paper, sediment loads are predicted using two different types of multilayer feedforward neural networks, namely Multi-Layer perceptron (MLP) and Radial Basis Function (RBF). The input variables for both structures are
considered to be flow discharge, mean flow depth and width, mean bed material’s diameter and water surface slope and the output is sediment discharge. Some different cases have been studied. The results are promising. It has been also observed that mean square prediction errors for the developed MLP is equal to 0.0063 while the devised RBF networks produces much larger mean square errors, namely 0.01260. This indicates that the MLP- load-predictor outperforms the RBF-predictor."