B. Baki
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13 records found
1
Marine renewables in Energy Systems
Impacts of climate data, generators, energy policies, opportunities, and untapped potential for 100% decarbonised systems
The deliverable offers an in-depth resource assessment for wind-wave-solar renewable energy resources along the European Atlantic region. The duration of information cover 1990-2021 (including 2021), resulting in 32 years. This deliverable uses state of the art high resolution data for wind and solar, and introduces the European Coasts High resolution Ocean WAVEs (ECHOWAVE) hindcast, a new open source database for wave conditions with superior accuracy. ECHOWAVE covers North Atlantic European waters within the coastal shelf, from intermediate to shallow water relative depths and is specially adjusted to improve the representation of sea states within the area of interest. This translates as a reduction of the uncertainties in the estimation of some of the most important wave parameters for wave energy applications. ...
The deliverable offers an in-depth resource assessment for wind-wave-solar renewable energy resources along the European Atlantic region. The duration of information cover 1990-2021 (including 2021), resulting in 32 years. This deliverable uses state of the art high resolution data for wind and solar, and introduces the European Coasts High resolution Ocean WAVEs (ECHOWAVE) hindcast, a new open source database for wave conditions with superior accuracy. ECHOWAVE covers North Atlantic European waters within the coastal shelf, from intermediate to shallow water relative depths and is specially adjusted to improve the representation of sea states within the area of interest. This translates as a reduction of the uncertainties in the estimation of some of the most important wave parameters for wave energy applications.
Advancements in floating offshore wind energy are unlocking the potential of the coastal waters of Portugal for the installation of wind farms. A thorough evaluation of coastal effects and variability across different time scales is crucial to ensure successful offshore wind farm investments. State-of-the-art atmospheric reanalysis datasets fall short in explaining the coastal effects due to their modest grid resolution. This study aims to fill this gap by simulating a 31-year wind dataset at a gray-zone resolution of 500 m using the Weather Research and Forecasting model, covering a significant portion of the Portugal coast. The gray-zone refers to grid scales of a few hundred meters, where turbulence is only partially resolved, traditional turbulence modeling breaks down, and large-eddy simulations are computationally prohibitive. The newly generated dataset has been validated with buoy observations and compared against reanalysis datasets, demonstrating improved performance and highlighting its higher fidelity in assessing wind resources. Two wind turbine power curves, the Leanwind 8 megawatt (MW) reference wind turbine (RWT), which has been commercialized, and the International Energy Agency (IEA) 15 MW RWT, which represents future commercialization, are considered in energy production calculations. In the simulated data, the Iberian Peninsula Coastal Jet (IPCJ) emerges as a crucial factor influencing wind maxima, especially during the summer months. The diurnal and annual variability of wind energy resources aligns with the occurrence of IPCJ, highlighting its impact on wind energy generation. The energy production capability of the 15 MW turbine model is demonstrated to be significantly higher, attributed not only to its increased capacity but also to the stronger jet winds near the turbine hub height. Interestingly, wind resources are not monotonically increasing with distance from the coastline, but a tongue-like resource maxima is observed, which is attributed to the IPCJ.
In Numerical Weather Prediction (NWP) models, such as the Weather Research and Forecasting (WRF) model, parameter uncertainty in physics parameterization schemes significantly impacts model output. Our study adopts a Bayesian probabilistic approach, building on prior research that identified temperature (T) and relative humidity (Rh) as sensitive to three key WRF parameters during southeast Australia's extreme heat events. Using Gaussian process regression-based Bayesian Optimisation (G-BO), we accurately estimated the optimal distributions for these parameters. Results show that the default values are outside their corresponding optimal distribution bounds for two of the three parameters, suggesting the need to reconsider these default values. Additionally, the robustness of the optimal parameter distributions is validated by their application to an independent extreme heat event, not included in the optimisation process. In this test, the optimized parameters substantially improved the simulation of T and Rh, highlighting their effectiveness in enhancing simulation accuracy during extreme heat conditions.
Machine learning based parameter sensitivity of regional climate models
A case study of the WRF model for heat extremes over Southeast Australia
Heatwaves and bushfires cause substantial impacts on society and ecosystems across the globe. Accurate information of heat extremes is needed to support the development of actionable mitigation and adaptation strategies. Regional climate models are commonly used to better understand the dynamics of these events. These models have very large input parameter sets, and the parameters within the physics schemes substantially influence the model’s performance. However, parameter sensitivity analysis (SA) of regional models for heat extremes is largely unexplored. Here, we focus on the southeast Australian region, one of the global hotspots of heat extremes. In southeast Australia Weather Research and Forecasting (WRF) model is the widely used regional model to simulate extreme weather events across the region. Hence in this study, we focus on the sensitivity of WRF model parameters to surface meteorological variables such as temperature, relative humidity, and wind speed during two extreme heat events over southeast Australia. Due to the presence of multiple parameters and their complex relationship with output variables, a machine learning (ML) surrogate-based global SA method is considered for the SA. The ML surrogate-based Sobol SA is used to identify the sensitivity of 24 adjustable parameters in seven different physics schemes of the WRF model. Results show that out of these 24, only three parameters, namely the scattering tuning parameter, multiplier of saturated soil water content, and profile shape exponent in the momentum diffusivity coefficient, are important for the considered meteorological variables. These SA results are consistent for the two different extreme heat events. Further, we investigated the physical significance of sensitive parameters. This study’s results will help in further optimising WRF parameters to improve model simulation.
The analysis is based on a first layer on coarse data, and will allow us to identify which resources have more “connectivity”. The resource assessment, even at coarse level, will indicate regions for further high resolution analysis, with better suited wind-wave-solar models. The correlation analysis is expected to showcase the potential of temporal overlaps by the different resources.
The Deliverable examines the overlap of stochastic conditions, the analysis will consider different “time windows” for the base resource, and assess its complementarity with other stochastic renewables. The aim of this deliverable is the estimation of overlap and production of mean maps that indicate to which extend each resource is connected. It is expected that the wind and wave resources will produce higher interest, due to their temporal variability. However, peak solar performance will also be analysed in terms of overlap with wind and/or wave. ...
The analysis is based on a first layer on coarse data, and will allow us to identify which resources have more “connectivity”. The resource assessment, even at coarse level, will indicate regions for further high resolution analysis, with better suited wind-wave-solar models. The correlation analysis is expected to showcase the potential of temporal overlaps by the different resources.
The Deliverable examines the overlap of stochastic conditions, the analysis will consider different “time windows” for the base resource, and assess its complementarity with other stochastic renewables. The aim of this deliverable is the estimation of overlap and production of mean maps that indicate to which extend each resource is connected. It is expected that the wind and wave resources will produce higher interest, due to their temporal variability. However, peak solar performance will also be analysed in terms of overlap with wind and/or wave.
The resource assessment, even at coarse level, can indicate regions for further high resolution analysis, with better suited wind-wave-solar models. The estimated energy densities of wind, wave and solar, are partially the main indicators, we also discuss the impacts of variability, as this is expected to alter the performance of power production, when each resource is utilised by specific technologies.
This report also introduces some of the main statistical approaches and ways to estimate the resource potentials. They will be used and expanded upon in forthcoming Deliverables that will also look into power production, via coupling of high fidelity wind-wave-solar models with specific renewable converters.
Finally, in this Deliverable we discuss the role of open source coarse data and underline their limitations for operational renewable energy projects. ...
The resource assessment, even at coarse level, can indicate regions for further high resolution analysis, with better suited wind-wave-solar models. The estimated energy densities of wind, wave and solar, are partially the main indicators, we also discuss the impacts of variability, as this is expected to alter the performance of power production, when each resource is utilised by specific technologies.
This report also introduces some of the main statistical approaches and ways to estimate the resource potentials. They will be used and expanded upon in forthcoming Deliverables that will also look into power production, via coupling of high fidelity wind-wave-solar models with specific renewable converters.
Finally, in this Deliverable we discuss the role of open source coarse data and underline their limitations for operational renewable energy projects.