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Offshore Wind in Portugal: Actual Situation and Future Perspectives [Resumo]
No full textABSTRACT: Portugal started the deployment of wind energy onshore in the early nineties, along with the majority of the European countries and soon became one of the countries with a highest share of wind in the electric energy mix. However, unlike northern “wind countries” the offshore deployment didn’t follow the onshore success story. There are several reasons for that, the most important being the bathymetry of the Portuguese Coast, that prevents the installation of the common fixed to the bottom offshore foundations. To overcome that limitation, Portugal had a very active role in the deployment of the offshore floating technology, being the second country in the world to develop, construct and operate a successful floating wind turbine, WindFloat and, shortly after, a floating wind plant, Wind Atlantic. Those projects demonstrated the adequacy of the floating technology for the existing offshore conditions while recent projects, e.g. PO SEURE OffshorePlan, were characterizing the estimated wind potential and indicated possible planning and deployment paths. In 2022, the Portuguese government created an offshore working group (through Despacho n.º 11404/2022) with the mission to: i) identify the optimal locations, i.e. having a higher estimated potential, a lower impact on the environment and maritime activities while enabling the connection to the existing onshore grid – those areas were finally approved in February 2025; ii) address the most adequate competitive models for the sea-use concessions; and iii) characterize the capacity of Portuguese ports to support the deployment of the wind offshore sector. In 2024, the Portuguese Government announced it would initiate the auction for offshore wind plants still in 2025. The presentation addresses the planning work of the recent years and indicates the next steps for the deployment of the offshore wind sector in Portugal.COST Action CA20109 Modenerlands, supported by COST (European Cooperation in Science and Technology
Como o trabalho do LNEG apoia a concretização do PNEC: Plano Nacional de Energia e Clima - Conheça 10 dos trabalhos do LNEG que contribuem para a concretização do PNEC
No full textUnprecedented U-Pb-Th SHRIMP and Lu-Hf isotopic data in zircon from Tandilia basement rocks, Argentina: new insights into Palaeoproterozoic and Neoproterozoic crustal reworking of the Rio de la Plata craton
No full textABSTRACT: We present new geochronological zircon data from the Siempre Amigos Hill (SAH), a small but representative portion of Tandilia Terrane within the R & iacute;o de la Plata Craton (RPC). U-Pb-Th SHRIMP data indicate a heterogeneous Palaeoproterozoic (Rhyacian) crust. A garnet-bearing granite (2165 +/- 16 Ma) hosts felsic (2108 +/- 13.6 Ma) to intermediate gneiss protolith (2104 +/- 8 Ma), andesite with a sanukitoid signature (2094 +/- 47 Ma) and granulites or charnockites. Additionally, calc-alkaline granitoids (2092 +/- 13 Ma) intruded, as a result of differentiation from an igneous mafic sanukitoid source. Localised low-temperature shear zones affected the sequence. Lu-Hf isotopic data for the post-orogenic stage (< 2.1 Ga) complement previous results, showing progressive negative epsilon Hf-(t) values. These isotopes suggest post-orogenic transtension. New Neoproterozoic ages (652 +/- 37 Ma, 618.4 +/- 11.2 Ma and 686 +/- 60 Ma) from granites, with low-to-very low zircon Th/U ratios, are presented as evidence of U-Th-Pb systems overprinting by Neoproterozoic (Cryogenian) thermal-hydrothermal events. Those Neoproterozoic ages are, within analytical uncertainty, equivalent to the 656 +/- 19 Ma metamorphic age obtained for the Palaeoproterozoic granulite. These new Neoproterozoic ages, suggests a thermal perturbation linked either to the collision of the Nico Perez Terrane against the passive margin of RPC, or the Neoproterozoic evolution of the Ventania System basement during the Brasiliano/ Pan-African orogeny
Phenological Development, Productivity, and Oil Profiles of Different Safflower Cultivars for Biofuel Production
No full textABSTRACT: The production of oilseed biomass to meet the demand of the energy sector is constrained by several factors, including regional soil and climate conditions, phenological and production issues, such as yield and oil profile, and the compatibility of these factors with the requirements of the energy sector. Safflower is a small oilseed, and its brief phenological cycle and high productivity, concentration, and oil profile distinguish it as a notable candidate for research on energy applications. The objective of this study was to analyze the germination, seed vigor, yield, and oil profile parameters of safflower cultivars (IMAmt 1470, IMAmt 894, and IMAmt S525) with a view to determining their potential as biomass for the biofuel production chain, especially biodiesel and renewable aviation hydrocarbons. Safflower cultivars displayed high germination rates and germination vigor after 12 months of storage. They also met the production standards of 6797.7 kg ha-1 in 2021. The cultivar IMAmt-S525 exhibited a high oil content of 35%. The oil compositions of the safflower cultivars included in this study were found to be 9.7% palmitic acid (IMAmt1470), 71.82% linoleic acid (IMAmt 894), and 41% oleic acid (IMAmt 894 harvest 2022). It is recommended that the following cultivars be selected for production: IMAmt 894, IMAmt-S525, and IMAmt 1470, taking into consideration the physiological, production, and oil composition parameters. Since all three cultivars have high standards of physiological quality, productivity, and oil yield, they have the potential to be used as biomass to diversify oilseed matrices for biofuels
Enhancing the Biorefinery of Chestnut Burrs, Part II: Influence of Pretreatment with Choline Chloride–Urea-Diluted Deep Eutectic Solvent on Enzymatic Hydrolysis
No full textABSTRACT: Agro-industrial chestnut waste derived from chestnut processing is usually discharged without further use. However, these residues are attractive due to their high-value composition, rich in sugars and lignin. Among these residues, chestnut burrs (CB) represent a promising feedstock for biorefinery applications aimed at maximizing the valorization of their main constituents. In this study, we propose an environmentally friendly approach based on deep eutectic solvents (DES) formed by choline chloride and urea (ChCl/U) (1:2, mol/mol) for the selective deconstruction of lignocellulosic architecture, followed by enzymatic hydrolysis to release second-generation (2G) fermentable sugars. Pretreatments were applied to raw CB, washed CB (W-CB), and the obtained solid fraction after prehydrolysis (PreH). Structural and morphological modifications, as well as crystallinity induced by DES pretreatment, were characterized using attenuated total reflectance Fourier-transform infrared spectroscopy (ATR-FTIR), field emission scanning electron microscopy (FE-SEM), and X-ray diffraction (XRD). Remarkable results in terms of effectiveness and environmental friendliness on saccharification yields were achieved for PreH subjected to DES treatment for 8 h, reaching approximately 60% glucan and 74% xylan conversion under the lower enzyme loading (23 FPU/g) and liquid-to-solid ratio (LSR) of 20:1 studied. This performance significantly reduces DES pretreatment time from 16 h to 8 h at mild conditions (100 degrees C), lowers the LSR for enzymatic hydrolysis from 30:1 to 20:1, and decreases enzyme loading from 63.5 FPU/g to 23 FPU/g, therefore improving process efficiency and sustainability
The Geological Survey Organisations in delivering Critical Raw Materials autonomy through a Geological Service for Europe
No full textABSTRACT: Europe’s dependence on foreign-sourced critical raw materials poses a significant threat to its strategic autonomy and competitiveness. In this paper, we examine the historical significance of mining in Europe, the current geopolitical complexities surrounding critical raw materials supply, and recent EU policy initiatives aimed at bolstering domestic critical raw materials production and processing and building resilient supply chains. We highlight the crucial role of National Geological Survey Organisations in delivering knowledge of Europe’s critical raw materials potential, as well as contributing to international partnerships through technical engagement and geoscientific diplomacy. National Geological Survey Organisations collect and compile data on mineral resources, often serving as a primary resource for national and regional decision-making. This work is now crucial at EU level, with National Geological Survey Organisations mandated under the EU Critical Raw Materials Act to deliver National Exploration Programs to promote exploration investment through technical de-risking, and to coordinate efforts and geoscientific data and knowledge management at pan-European level. The National Geological Survey Organisations already share knowledge and best practices on European mineral resources through EuroGeoSurveys. Future efforts to secure European critical raw materials resilience will be served through their shared vision of a Geological Service for Europe
From Day-Ahead to a 6-Hour Period-Ahead Market Adapted to the Stochastic Behaviour of Variable Energy Renewable Sources
No full textABSTRACT: The existing electricity market design challenges the fair and competitive participation of variable renewable energy sources (vRES) due to their weather dependence and limited forecasting accuracy, especially for long-time horizons, as required in the day-ahead market (DAM). These challenges impact market clearing prices and create imbalances, leading to inefficiencies, such as market-splitting events. To enhance the market efficiency and fairness for vRES producers, this work proposes a period-ahead market (PAM) with a 6-hour rolling horizon instead of the traditional 24-hour DAM. A case study of the Iberian electricity market with 2030 energy mix scenarios for Portugal and Spain, demonstrates that, in PAM, vRES producers can reduce wind and solar power forecast errors by over 7 % and 4 %, respectively, when compared with DAM. This leads to a 2 % decrease in electricity prices and an annual reduction of marketsplitting events in 158 hours thus enhancing price harmonization between Portugal and Spain. Additionally, balancing prices also decreased in PAM benefiting the balance responsible parties. The findings highlight that PAM improves the market's efficiency, a key factor in the pathway for the decarbonization of power systems
The H2Excellence Project-Fuel Cells and Green Hydrogen Centers of Vocational Excellence Towards Achieving Affordable, Secure, and Sustainable Energy for Europe
No full textABSTRACT: The demand for green hydrogen (H2) and related technologies is expected to increase in the coming years, driven by climate changes and energy security of supply issues, amid the European and global energy crises. The European Green Deal and REpowerEU Plan have identified H2 as a key pillar for reaching climate neutrality by 2050 and for the intensification of hydrogen delivery targets, bringing the large-scale adoption of hydrogen production and applications, and stressing the need for a skilled workforce in emergent H2 markets. To that end, the H2Excellence project will establish a Platform of Vocational Excellence in the field of fuel cells and green hydrogen technologies, with an educational and training scheme to tackle identified skill gaps and to implement life-long learning opportunities. This project aims to become a European benchmark in training and knowledge transfer, incorporating the entire hydrogen value chain. The work is supported by the
Knowledge Triangle Model, integrating education, research, and innovation efforts to build a dynamic ecosystem in the green hydrogen sector. In this work, activities conducted so far by LNEG as a project partner and expected impacts are highlighted. Those activities are based on a stakeholder needs assessment conducted by project partners and on the
knowledge and experience accumulated in research activities developed in the Materials for Energy research area
Optimized Planning Framework for Radial Distribution Network Considering AC and DC EV Chargers, Uncertain Solar PVDG, and DSTATCOM Using HHO
No full textABSTRACT: This study aims to provide an efficient framework for the coordinated integration of AC and DC chargers, intermittent solar Photovoltaic (PV) Distributed Generation (DG) units, and a Distribution Static Compensator (DSTATCOM) across residential, commercial, and industrial zones of a Radial Distribution Network (RDN) considering the benefits of various stakeholders: Electric Vehicle (EV) charging station owners, EV owners, and distribution network operators. The model uses a multi-zone planning method and healthy-bus strategy to allocate Electric Vehicle Charging Stations (EVCSs), Photovoltaic Distributed Generation (PVDG) units, and DSTATCOMs. The proposed framework optimally determines the numbers of EVCSs, PVDG units, and DSTATCOMs using Harris Hawk Optimization, considering the maximization of techno-economic benefits while satisfying all the security constraints. Further, to showcase the benefits from the perspective of EV owners, an EV waiting-time evaluation is performed. The simulation results show that integrating EVCSs (with both AC and DC chargers) with solar PVDG units and DSTATCOMs in the existing RDN improves the voltage profile, reduces power losses, and enhances cost-effectiveness compared to the system with only EVCSs. Furthermore, the zonal division ensures that charging infrastructure is distributed across the network increasing accessibility to the EV users. It is also observed that combining AC and DC chargers across the network provides overall benefits in terms of voltage profile, line loss, and waiting time as compared to a system with only AC or DC chargers. The proposed framework improves EV owners' access and reduces waiting time, while supporting distribution network operators through enhanced grid stability and efficient integration of EV loads, PV generation, and DSTATCOM
Techno-economic analysis of a novel hybrid wind-wave floating platform concept: The OctaPlat
No full textABSTRACT: This work focuses on the techno-economic analysis of a novel floating offshore hybrid wind-wave platform. Floating multi-purpose platforms can potentially reduce costs associated with floating offshore wind. This work is based on the OctaPlat, a barge-type hybrid wind-wave floating platform designed at Instituto Superior Técnico, University of Lisbon. The paper presents the concept and numerical model of the floating wave platform, comprising five oscillating water column (OWC) wave energy converters, which was implemented in the object-oriented non-causal Modelica language. The OctaPlat configuration investigated here was equipped with the 15 MW IEA reference wind turbine, whose power output was computed using OpenFAST©. A sensitivity analysis of the geometry was performed, and the best performer design reached an average annual wave turbine power of 2.5 MW and a total wind-wave power of about 10.75 MW for a selected site off the west coast of Portugal. The levelized cost of energy (LCOE) was determined for a farm in the selected location. Various scenarios were assessed, and a Monte Carlo approach resulted in a probable value of LCOE of 135 €/MWh, with LCOE P90 and LCOE P10 values of 99 and 180 €/MWh, respectively. Experimental tests of the wave energy conversion systems were performed on a scale of 1:100, and comparisons with numerical results showed good agreement, with a coefficient of determination (R 2) of approximately 0.94 and relative differences were less than 20%, except for a few peak deviations. These results reveal the potential competitiveness of wind-wave multi-purpose platforms in floating offshore renewable energy projects