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New forecast tools to enhance the value of VRE on the electricity markets : 2nd Edition
No full textProject TradeRES - New Markets Design & Models for 100% Renewable Power SystemsABSTRACT: The present deliverable was developed as part of the research activities of the TradeRES project Task 4.4 - Enhancing the value of VRE on the electricity markets with advanced forecasting and ramping tools edition 2. This report presents the second edition of deliverable 4.9, which consists of the description and implementation of the forecasting models aiming to identify and explore the time synergies of meteorological effects and electricity market designs explored in the project to maximize the value of variable renewable energy systems and minimize market imbalances. An overview of key aspects that characterize a power forecast system is presented in this deliverable through a literature review. This overview addresses the: i) forecast time horizon; ii) type of approach (physical, statistical or hybrid); iii) data pre-processing procedures; iv) type of forecast output; and v) the most common metrics used to evaluate the performance of the forecast systems. While in the TradeRES project work package 3 the conception of new market designs and products are presented from a theoretical point of view, in this deliverable, the power forecast tools capable to address the new designs and products are presented and discussed. Complementarily to the first edition of this deliverable, the link between dayahead market time frames and the performance of the different power forecast approaches is analysed. This second edition of D4.9 also focuses on the short-term forecasts (below six hours) for new market designs. As a first step, a non-disruptive change in the day-ahead market is proposed by simply
postponing the gate closure hour according to the meteorological data availability from the global numerical weather prediction (NWP) models while the 24 hours forecast periods are still used. In the second step, various short-term forecast approaches designed for time horizons below six hours are developed and implemented. These approaches are specifically tailored to attend the requirements of new electricity market designs currently under development in TradeRES. Another aspect regarding the meteorological time synergy and electricity markets analysed in this deliverable is the identification of extreme events. A wind power ramping
forecast approach implemented in the TradeRES forecast tools is described. This approach is designed to complement the existing deterministic power forecasts and it can be used to increase the transmission system operators’ awareness level and helping them to better scale the level of reserve required. Market players can also take advantage of this information to strategically define the bids in the different market environments.
Using different wind and solar power parks in Portugal, as well as the national aggregated Portuguese and German wind and solar generation, results regarding the potential certainty gain effect from changing the day-ahead market gate closure are presented and analysed in this deliverable. Results showed that the use of the TradeRES forecast methodology guaranteed better performance compared to an operational forecast from a forecast provider. Additionally, the results emphasized the benefits of including non-traditional variables such as air pressure and temperature at different heights, atmospheric boundary layer, and geopotential height for various pressure levels. The simulations also highlighted that incorporating both NWP features based on historical power series led to improvement when compared with models based solely on power series or NWP. Therefore, it is recommended that power forecast systems can have access to recent observed values to
improve their accuracy. Despite the improvements achieved in the forecasts for the day-ahead market, high
power forecast errors are still observed (a normalised root mean square error of nearly 30% for wind and solar in Portugal and nearly 20% for Spain). Market designs with shorter forecast time horizons can significantly reduce power forecast errors. Results also emphasize the importance of evaluating the most suitable forecast approach based on the forecast time horizon. To assess the value of renewable energy forecasting for the German day-ahead market, the Agent-based Market model for the Investigation of Renewable and Integrated energy Systems (AMIRIS) was enhanced to account for power forecast errors. For this purpose, a feature was developed that allows for the adjustment of forecasts for the feed-in of renewable energies using a Gaussian distributed error term. Furthermore, this deliverable presents a realistic forecast time series that was implemented in AMIRIS. The case study of the German day-ahead market in 2019 demonstrated that realistic power forecasts can reduce the profits of onshore wind turbine operators by approximately 8% compared to perfect foresight of wind infeed. Assuming Gauss-distributed errors, the losses are smaller (~ 5 % less profit compared to the perfect forecast). The power forecast tools developed in this task will be publicly shared and disseminated in the channels of the project. With this step, users can use the tools for obtaining power forecasts in future studies or use the approaches developed in TradeRES as a benchmark.N/
Performance assessment of current and new market designs and trading mechanisms for national and regional markets : Deliverable D5.3
No full textProject TradeRES - New Markets Design & Models for 100% Renewable Power SystemsN/
Municipal and industrial wastewater blending: Effect of the carbon/ nitrogen ratio on microalgae productivity and biocompound accumulation
No full textABSTRACT: Municipal wastewater (MW) and industrial wastewater from juice processing (IWJ) were blended in different proportions to assess the effect of the carbon/nitrogen (C/N) ratio on pollutant removal, microalgal biomass (MB) cultivation, and the accumulation of carotenoids and biocompounds. MB development was not observed in treatments with higher C/N ratios (>30.67). The wastewater mixture favored the removal of dissolved organic carbon (75.61 and 81.90%) and soluble chemical oxygen demand (66.78-88.85%), compared to the treatment composed exclusively of MW (T7). Treatments T3 and T6 (C/N ratio equal to 30.67 and 7.52, respectively) showed higher Chlorophyll-a concentrations, 1.47 and 1.54 times higher than T7 (C/N ratio 1.75). It was also observed that the C/N ratio of 30.67 favored the accumulation of carbohydrates and lipids (30.07% and 26.39%, respectively), while the C/N ratio of 7.52 improved protein accumulation (33.00%). The fatty acids C16:0, C18:1, C18:2, and C18:3 had the highest concentrations. Additionally, increasing the C/N ratio can be an efficient strategy to improve the production of fatty acids for biofuels, mainly due to the increased concentration of shorter-chain fatty acids (C16:0). These findings suggest that blending wastewater not only enhances treatment performance but also increases the accumulation of valuable carbohydrates and lipids in MB, and optimizes fatty acid production for biofuel applications. This research represents significant progress towards feasibility of using MB produced from wastewater.info:eu-repo/semantics/publishedVersio
Enhanced Renewable Power Forecasting through NWP and Historical Power Data Integration [Comunicação oral]
No full textN/
The role of research-based spin-offs in innovation ecosystems
No full textABSTRACT: The objective of the paper is to contribute to a better understanding of the various roles played by research-based spin-offs (RBSOs) in knowledge dissemination. It investigates if RBSOs act as connectors and knowledge translators, both between different types of organisations within an innovation ecosystem and across different geographical scales and knowledge environments. This latter role has been relatively less investigated but is important to open local innovation ecosystems. The paper analyses the networks formed by Portuguese RBSOs in the context of research, technology and product development projects. The results suggest that RBSOs play an intermediary role in the country’s innovation ecosystem, which can assume different forms. In the national networks, they frequently bridge between research and downstream organisations, contributing to the dissemination of knowledge within the ecosystem. In the international networks, their most important role may be as connectors to and conveyors of advanced knowledge produced in external knowledge environments.info:eu-repo/semantics/publishedVersio
Innovative approach in sustainable agriculture: Harnessing microalgae potential via subcritical water extraction
Get PDFABSTRACT: Microalgae can contribute to sustainable agriculture and wastewater treatment. This study investigated Tetradesmus obliquus, grown in piggery wastewater (To-PWW), as a biostimulant/biofertilizer compared to biomass grown in synthetic medium (To-B). Subcritical water extraction was tested for disruption/hydrolysis of wet biomass, at three temperatures (120, 170, and 220 °C) and two biomass loads (1:10 and 1:80 (g dry biomass/mL water)). Extracts were evaluated for germination, and root formation/expansion. Residues were quantified for nutrient composition to assess their biofertilizer potential and tested for their affinity to oil compounds for bioremediation. The best germination was achieved by To-B extracts at 170 °C (1:10: 148 % at 0.2 g/L, 1:80: 145 % at 0.5 g/L). Only To-PWW extracts at 0.2 g/L had a significant germination effect (120 °C: 120–123 % for both loads; 170 °C: 115 % for 1:80). To-PWW extract at 120 °C and 1:10 significantly affected cucumber and mung bean root formation (224 and 268 %, respectively). Most extracts significantly enhanced root expansion, with all To-B extracts at 1:10 showing the best results (139–181 %). The residues contained essential nutrients (NPK), indicating their biofertilizer potential, helping decrease synthetic fertilizers demands. To-B residues had high affinity to toluene and diesel but lower to used cooking and car oils. To-PWW showed very low affinity to all oil compounds. Finally, all residues were only able to form stable emulsions with the used car oil. This study fully exploits the use of microalgal biomass in sustainable agriculture, producing biostimulant extracts, and residues for biofertilizer and bioremediation, from a low-cost wastewater source.info:eu-repo/semantics/publishedVersio
A Methodology for Dynamic Procurement of Secondary Reserve Capacity in Power Systems with Significant vRES Penetrations
No full textABSTRACT: The European pathway to carbon neutrality indicates strong investments in variable renewable energy sources. Demand-side and variable renewable players rely on forecasts to participate in day-ahead markets closing between 12 and 37 hours ahead of real-time operation. As such, the further from the real-time operation those forecasts are provided, the higher their errors and the uncertainty. Deviations from the market schedules are balanced using real-time reserves. Traditionally, transmission system operators (TSOs) use a symmetrical procurement of up and down reserves based on the expected demand. This work considers the computation of a dynamic up and down procurement of secondary capacities by considering the expected deviations, using the day-ahead programmed and expected dispatches of variable renewables, demand, other technologies, and the cross-border capacities. The study uses operational open data from the Spanish TSO from 2019 to 2022. The proposed methodology allows increasing the usage of the up and down secondary capacities by almost 13% and 8%, respectively, freeing up 11% of the allocated resources, on average.info:eu-repo/semantics/publishedVersio
Nivelamento de dados para corrigir efeitos de bordadura, provenientes de diferentes levantamentos de prospeção geoquímica
Get PDFABSTRACT: The existence of a large number of chemical analyses resulting from decades of geochemical exploration campaigns, yields huge numbers of analytical results produced with different analytical methods, sampling protocols and sampling means. Therefore, it is necessary to level these analytical results to make them comparable and thus take advantage of the potential of geochemical information from contiguous areas. In this study, a levelling technique was used on geochemical datasets of tested bands between the 1:25 000 scale maps, 293/294 and 305/306 sheets, respectively, from the Beira Baixa region where stream sediments were sampled during a project for rare earth elements exploration. These samples were analysed for lanthanum by the same analytical methods and in the same laboratory, but in different periods and the border effects were observed. These levelling techniques must be adapted to the data to be compared and in the present case the disappearance of the border effect of the analytical results of 293/294 and 305/306 topographic sheets was observed.RESUMO: A existência de um grande número de análises químicas resultantes de décadas de campanhas de prospeção geoquímica produz um grande número de resultados analíticos com diferentes métodos analíticos, protocolos e meios de amostragem. Nesse sentido, é necessário nivelar estes resultados analíticos para torná-los comparáveis e assim aproveitar o potencial da informação geoquímica de áreas contíguas. Neste estudo foi utilizada uma técnica de nivelamento de dados de geoquímica baseada em bandas testadas com larguras variadas entre os mapas à escala 1:25 000, 293/294 e 305/306, respetivamente, da região da Beira Baixa. Nestes, foram amostrados sedimentos de corrente durante um projeto de prospeção de Elementos de Terras Raras. Essas amostras foram analisadas para lantânio pelos mesmos métodos analíticos e no mesmo laboratório, mas em períodos diferentes e foram observados efeitos de bordadura. As técnicas de nivelamento foram adaptadas aos dados a comparar e observou-se o desaparecimento do efeito bordadura dos resultados analíticos entre as cartas topográficas 293/294 e 305/306.info:eu-repo/semantics/publishedVersio
The behavior of thermally modified wood after exposure in maritime/industrial and urban environments
Get PDFABSTRACT: Natural and thermally modified Pine, Ash, and Acacia woods were exposed in two different environments: urban and maritime/industrial. The weathering effects were evaluated during 24 months regarding color, chemical, and structural changes. In all wood species, thermal modification induced color, chemical, and structural changes. All woods became darker (Pine Delta L*: -32.01; Ash Delta L*: -36.83; Acacia Delta L*: -27.50), total extractives content increased (Pine: 19 %; Ash: 32 % and Acacia: 18 %), and the samples presented deformation and damaged cells. Total lignin was not significantly changed, although there were detected changes in lignin, namely the reduction of G -units in Pine (approximate to 2 %) and reduction of S/G ratio in Acacia (approximate to 0.04 %). Ash remained almost the same. After weathering, modified woods suffered fewer color changes, indicating that the thermal modification could improve the resistance to color change. Acacia wood, when exposed to maritime/industrial conditions, revealed a higher color change (Delta E: 35.7 at 24 months) when compared with urban conditions (Delta E: 23.5 at 24 months). Delignification, possibly caused by photodegradation, occurred in all wood samples, and the loss of extractive happened, perhaps caused by rain. Modified woods were slightly less resistant to weathering in maritime/ industrial environments. Some structural damage, namely cracked cells, the appearance of molds, blue staining, and particle deposition, was observed. The thermal modification enables color stabilization but does not seem to improve the weathering resistance in all studied wood species. Exposure to the different environments did not lead to significant differences in the morphology and chemical composition of the three natural and modified wood species.info:eu-repo/semantics/publishedVersio