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The open-source tool AWERA was developed for assessing the potential of airborne wind energy systems (AWES) on large geographical and temporal scales. AWERA can be used for spatial and temporal studies of the wind resource and power production potentials and means for comparing different types of AWESs. It can also be used for uncertainty quantification of the computed power production for all simulation components, from wind resources to system dynamics. AWES are characterised by a more complex power generation than conventional wind turbines. Flight operation and harvesting depend not only on the wind speed at hub height but on an extended vertical wind profile and its temporal variation. Accounting for the specific harvesting process leads to a substantially improved performance estimation. AWERA employs simplified quasi-steady force equilibrium states along the flight trajectory of the kite to estimate the power output for a given vertical wind profile. Using a principal component analysis paired with a clustering algorithm on an ensemble of measured vertical wind profiles, eight representative absolute wind profiles are identified. The harvesting characteristics are determined for the absolute clustering wind profiles, which then are used to obtain the spatial distribution of the annual energy production for Europe, significantly reducing the computing time compared to processing all samples individually. For validation, harvesting characteristics resulting from either approach are compared for various clustering representations. AWERA can include different AWES types and power production estimation models. The resulting hourly power is used to compute the annual energy production and capacity factor and to evaluate characteristics such as the downtime, which can be used to assess the potential for providing base load capacity.

Wind lidar are often used to supply the wind data needed for wind resource assessments. In this review by members of IEA Wind Task 32 we give our perspective on the current best practices when deploying vertically-profiling wind lidar for wind resource assessments in 2020. This review is particularly intended for use by new users who wish to understand the standards landscape for this use case. This document is also available through our GitHub repository at https://github.com/IEA-Wind-Task-32/RP15-status-update/releases/tag/1.0., Feedback about this review should be directed to https://github.com/IEA-Wind-Task-32/RP15-status-update/issues or to the Task 32 Operating agents at ieawind.task32@ifb.uni-stuttgart.de.

We present here the Data Management Plan for my PhD project. A major part of the project involved the planning and execution of a full-scale wind mapping experiment called the Alaiz Experiment (ALEX17). This document outlines the main objectives of the project, the data collection, data storage, documentation of the experiment, data sharing strategies and the long-term preservation of the dataset.

Overview of IEC 61400-15 standard, timeline and call for participation

This presentation was done at the NEWA Final Workshop in April 2019. It presents a summary of the research activities related to the development of the NEWA model chain, which has two branches:one dedicated to the production of the wind atlas, based on the WRF model and statistical downscaling with the WAsP methodology, and another one focused on site assessment tools, based on dynamic downscaling with a variety of computational fluid dynamic (CFD) codes, using both Reynolds-Averaged Navier Stokes (URANS) and Large-Eddy Simulation (LES) turbulence modeling. Alongside model development activities a formal verification and validation (V&V) strategy was implemented, following the IEA Task 31 Wakebench framework, to leverage the experimental database of the project.An open-source model chain based on WRF and OpenFOAM has been released as reference for future model development and validation activities in connection to wind assessment best practices and standards.

Presentation at the NEWA Final Workshop in Bilbao. The Rödeser Berg forested hill experiment near Kassel is presented leading to two rounds of blind tests for wind flow models in different stability conditions. A follow up benchmark is underway related to the assessment of annual energy production (AEP).&nbsp

Presentation at the NEWA Final Workshop in Bilbao. TheRyningsnäs atmospheric boundary-layer experiment in a Swedish forested landscape is used to set up a benchmark for wind energy flow models to simulate the flow above a forest canopy that is characterized using aerial laser scans. The footprint characteristics of the canopy are visible in the profiles. The benchmark includes results from RANS and LES models showing good consistency in the mean velocity profiles and less agreement in TKE profiles.&nbsp

Presentation at the NEWA Final Workshop in Bilbao. It provides a description of the RUNE and Balcony experiments using scanning lidars, among other systems, to measure the the flow field in a coastal transition (RUNE) and above a patchy forest canopy (Balcony). Both experiments are available open-access.

Presentation at the NEWA Final Workshop in Bilbao with an overview that summarizes some of the most important highlights of the project.

The physical effects of upstream flow obstructions such as vegetation on cross-ventilation phenomena of a building are important for issues such as indoor thermal comfort. Modelling such effects in Computational Fluid Dynamics simulations may also be challenging. The aim of this work is to establish the cross-ventilation jet behaviour in such complex terrain conditions as well as to provide guidelines on the implementation of CFD numerical simulations in order to model complex terrain features such as vegetation in an efficient manner. The methodology consists of onsite measurements on a test cell coupled with numerical simulations. It was found that the cross-ventilation flow is highly turbulent despite the very low velocities encountered internally within the test cells. While no direct measurement of the jet direction was made, the measurements indicate that flow tends to be reversed from the leeward to the windward side. Modelling such a phenomenon proves challenging and is strongly influenced by how vegetation is modelled. A solid vegetation tends to predict better the direction and magnitude of the flow than a porous vegetation approach. A simplified terrain model was also shown to provide good comparisons with observation. The findings have important implications on the study of cross-ventilation in complex terrain conditions since the flow direction does not remain trivial, as with the traditional isolated building case., {"references":["M. Shirzadi, M. Naghashzadegan, and P. A. Mirzaei,\n\"Improving the CFD modelling of cross-ventilation in\nhighly-packed urban areas,\" Sustainable Cities and Society,\nvol. 37, pp. 451–465, 2018. (Online). Available:\nhttp://www.sciencedirect.com/science/article/pii/S2210670717312891.","R. Ramponi and B. Blocken, \"CFD simulation of cross-ventilation for a\ngeneric isolated building: Impact of computational parameters,\" Building\nand Environment, vol. 53, pp. 34–48, jul 2012. (Online). Available:\nhttp://www.sciencedirect.com/science/article/pii/S0360132312000133.","L. Wang and N. H. Wong, \"Coupled simulations for\nnaturally ventilated rooms between building simulation (BS)\nand computational fluid dynamics (CFD) for better prediction\nof indoor thermal environment,\" Building and Environment,\nvol. 44, no. 1, pp. 95–112, jan 2009. (Online). Available:\nhttp://www.sciencedirect.com/science/article/pii/S0360132308000231.","A. H. Abdullah and F. Wang, \"Design and low energy\nventilation solutions for atria in the tropics,\" Sustainable Cities\nand Society, vol. 2, no. 1, pp. 8–28, 2012. (Online). Available:\nhttp://www.sciencedirect.com/science/article/pii/S2210670711000606.","A. Mochida, H. Yoshino, S. Miyauchi, and T. 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This document is a consensus update on the general progress and outputs from the IEC 61400-15 working group.

This document is a consensus update on the general progress and outputs from the IEC 61400-15 working group.

This document is a consensus update on the general progress and outputs from the IEC 61400-15 working group.&nbsp

This document is a consensus update on the general progress and outputs from the IEC 61400-15 working group.

This document describes the official work scope for the IEC 61400-15 working group for the Assessment of Wind Resource, Energy Yield and site suitability input conditions for wind power plants

This document describes the official work scope for the IEC 61400-15 working group for theAssessment of Wind Resource, Energy Yield and site suitability input conditions for wind power plants

The wind resource assessment campaign represents one of the most important phases in the development of utility-scale wind farms. The energy production estimates that are generated based upon the results of the wind measurement campaign are essential in determining the feasibility of a proposed wind farm project. This handbook presents industry-accepted guidelines for planning and conducting a wind resource assessment program. Included is a comprehensive overview of the wind monitoring process, which involves the siting, installation, and operation of a meteorological towers, as well as advanced remote sensing technologies. Recommended best practices for the subsequent data collection and validation are provided. Advancing beyond the initial wind monitoring and data collection phases, a detailed discussion of the analytical methods involved with estimating a site’s wind energy potential is presented. These analyses include extrapolating observed wind measurements to hub height, adjusting the measured data to the long-term historical norm, wind flow modeling, and the assessing the uncertainty associated with resulting energy production estimates. This handbook will provide the assessor with detailed understanding of the wind resource assessment process, as well as the analyses involved with the estimating wind farm energy production., funding provided by NEW YORK STATE ENERGY RESEARCH AND DEVELOPMENT AUTHORITY (NYSERDA)

Presentation at the NEWA Final Workshop in Bilbao. The Rödeser Berg forested hill experiment near Kassel is presented leading to two rounds of blind tests for wind flow models in different stability conditions. A follow up benchmark is underway related to the assessment of annual energy production (AEP).

Presentation at the NEWA Final Workshop in Bilbao. Overview of SAR and Scatterometer satellite wind maps useful for quantification of coastal effects, wind farm effects and for the validation of models for pre-site assessment.

Presentation at the NEWA Final Workshop in Bilbao. The use of stationary cellular communication masts for wind speed measurements provides a valid option for significantly reducing the time and material resources required to study the potential of wind energy at the height of up to 100 meters above ground level. This study show how to set up wind assessment campaigns using these masts and the how to account for directional-dependent flow distortion due to the presence of the tower.

Presentation at the NEWA Final Workshop in Bilbao.The use of stationary cellular communication masts for wind speed measurements provides a valid option for significantly reducing the time and material resources required to study the potential of wind energy at the height of up to 100 meters above ground level. This study show how to set up wind assessment campaigns using these masts and the how to account for directional-dependent flow distortion due to the presence of the tower.

Presentation at the NEWA Final Workshop in Bilbao. Overview of SAR and Scatterometer satellite wind maps useful for quantification of coastal effects, wind farm effects and for the validation of models for pre-site assessment.&nbsp

Presentation at the NEWA Final Workshop in Bilbao. The Ryningsnäs atmospheric boundary-layer experiment in a Swedish forested landscape is used to set up a benchmark for wind energy flow models to simulate the flow above a forest canopy that is characterized using aerial laser scans. The footprint characteristics of the canopy are visible in the profiles. The benchmark includes results from RANS and LES models showing good consistency in the mean velocity profiles and less agreement in TKE profiles.