• Energy Research

The concept of “Virtual Renewable Power Plants - VRPP” enables several positive factors for the electric integration of Renewable Energy Sources (RES), namely (a) the smoothing of time based fluctuation of the power delivered by the RES, (b) the use of the natural complementary of renewable resources availability (c) the establishment of synergies between different RES as well as the combination of their production. The present work aims to identify the synergies between wind and photovoltaic (PV) plants, regarding their daily profiles l complementarity and resource availability; as well as the technical and economic added value of a VRPP. Results show an increase of 5.3% in the capacity factor when 2 MWp of PV is added to an 8 MW wind farm, considering all infrastructural capacity limits. Moreover, additional results include the characterization and optimization of hybrid virtual wind-PV plants production profile.

AbstractThis paper provides an overview of major transmission planning activities related to wind integration studies in the United States and Europe. Transmission planning for energy resources is different from planning for capacity resources. Those differences are explained, and illustrated with examples from several regions of the United States and Europe. Transmission planning for wind is becoming an iterative process consisting of generation expansion planning, economic‐based transmission planning, system reliability analysis, and wind integration studies. A brief look at the policy environment in which this activity is taking place is provided. A set of coherent and collaborative transmission planning, siting, and permitting policies and cost allocation method must be developed to achieve the intended objectives. The scale of transmission development envisioned for this purpose will require unprecedented cooperation across multiple jurisdictional boundaries.This article is categorized under: Wind Power > Systems and Infrastructure Energy Infrastructure > Systems and Infrastructure Energy Systems Economics > Systems and Infrastructure

The increase in the wind power predictability assumes a very important role for secure power system operation at minimum costs, especially in situations with severe changes in wind power production. In order to improve the forecast of such events, also known as “wind power ramp events”, the underlying role of some severe meteorological phenomena in triggering wind power ramps must be clearly understood. In this paper, windstorm and cyclone detection algorithms are implemented using historical reanalysis data allowing the identification of key characteristics (e.g., location, intensity and trajectories) of the events with the highest impact on the wind power ramp events in Portugal. The results show a strong association between cyclones/windstorms and wind power ramp events. Moreover, the results highlight that it is possible to use some features of these meteorological phenomena to detect, in an early stage, severe wind power ramps thus creating the possibility to develop operational decision tools in order to support the security of power systems with high amounts of wind power generation.

Abstract This paper presents a systemic modeling for a PV system integrated into an electric grid. The modeling includes models for a DC–DC boost converter and a DC–AC two-level inverter. Classical or fuzzy PI controllers with pulse width modulation by space vector modulation associated with sliding mode control is used for controlling the PV system and power factor control is introduced at the output of the system. Comprehensive performance simulation studies are carried out with the modeling of the DC–DC boost converter followed by a two-level power inverter in order to compare the performance with the experimental results obtained during in situ operation with three commercial inverters. Also, studies are carried out to assess the quality of the energy injected into the electric grid in terms of harmonic distortion. Finally, conclusions regarding the integration of the PV system into the electric grid are presented.

ABSTRACT: s the share of VRE (variable renewable energy) has grown rapidly, curtailment issues have arisen worldwide. This paper evaluates and compares curtailment situations in selected countries using an objective and quantitative evaluation tool named the "C-E map " (curtailment-energy share map). The C-E map is a correlation map between curtailment ratios that mean curtailed wind (or solar) energy per available energy and energy shares of wind (or solar). The C-E map can draw a historical trend curve in a given country/area, as an at-a-glance tool to enable historical and/or international comparison. The C-E map also can classify the given countries/areas into several categories, according to the current levels of curtailment ratio and historical trends. The C-E map helps institutional and objective understanding of curtailment for non-experts including policy makers. info:eu-repo/semantics/publishedVersion

Abstract An accurate offshore wind resource assessment is a key tool for planning marine wind renewable exploitation. To achieve this goal, without resort to an extensive and costly network of anemometric stations or buoys, it becomes necessary to use the so-called atmospheric mesoscale models. This work presents a high spatial resolution (1x1 km) offshore wind resource Atlas for Portugal and the model calibration steps. During the calibration steps, the most adequate: i) atmospheric parameterizations - physics options, ii) initial and boundary conditions (IBC) meteorological datasets, and iii) data assimilation scheme were achieved through sensitivity tests using the common statistical metrics and hourly simulated/observational data. Results show that the most significant improvements are associated with the IBC dataset and the data assimilation scheme used. Thus, the results show that the assimilation procedures coupled with the new ERA-5 reanalysis dataset reduce significantly the errors of the wind speed and direction, especially the normalized mean square error. This reduction, depending on the different calibration setup, can be above 50%. The new Atlas confirms the previous indicators, Portugal presents a high wind power potential, especially for deep offshore regions.

ABSTRACT: This deliverable presents the approach implemented to perform a stakeholder analysis and to produce the TradeRES’ stakeholder engagement plan. It includes the description of the tools used for the stakeholder engagement, namely the webinars, tutorials, experiments and surveys. Before establishing the engagement plan, the identification and prioritization of the relevant stakeholders at the European and national levels are performed. To support this step, a stakeholder mapping approach is followed by clustering each target group into the following categories: “Key player”, “Meet their needs”, “Keep informed” and “Monitor”. This classification takes into account the level of interest and influence of each stakeholder in the project. The communications between the consortium and the stakeholders as well as the preferable channels for these communications are also presented. The engagement plan includes a description of the communication tools, objective, frequency and expected contribution of the different stakeholders. The project comprises different stakeholders to follow closely the work developed providing feedback on the modelling methodology and scope, on market design choices, and on our research results. The stakeholders’ knowledge has been effectively involved since the beginning of the project, namely in activities related to construct reference energy systems for 2030, and their role will be crucial during the iterative process of shaping market designs and testing as well as validating the newly developed open-access market tools.