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Wind power is one of the most important renewable energy sources worldwide. However, integrating these technologies in electricity markets faces challenges due to the intermittent wind speed, resulting in potential imbalances within power grids and subsequent inefficiencies. Traditional approaches for modeling the uncertainty simulate fixed wind power values in operational and planning models, which work well for the short term but are inadequate for medium-term decision-making due to lower forecasting accuracy and the inability to differentiate the imbalance risk faced in each simulated value. This paper proposes a novel methodology for incorporating wind energy imbalance risk into medium-term generation planning models. For this, we first simulate realistic wind power scenarios and perform a fitting distribution process to characterize the hourly wind power behavior. Then, we model the imbalance risk using quadratic-uncertainty cost functions for each simulated value. Subsequently, we conduct a temporal aggregation to reduce the computational burden, preserving the conceptual framework of the imbalance risk modeling. Finally, we propose a medium-term generation planning model that includes the imbalance risk model and the temporal aggregation strategy. Our approach is evaluated in a real-size case study formed by Spain, Portugal, and France's electricity markets, demonstrating accurate wind power imbalance risk modeling and lowered planning costs. • A new methodology to include wind energy imbalance risk in generation planning models. • Introducing a fitting process for modeling the distribution asymmetries of wind power. • Proposing a temporal aggregation method for efficient imbalance risk modeling. • The methodology is validated in Spanish, Portuguese, and French electricity markets. [ABSTRACT FROM AUTHOR]

This paper presents the results of the explorations carried out in the western sector of the Iberian Central System (western Gredos, Béjar, Gata and Estrela mountain ranges). The macroremains found allow detailing the model of the landscape transformation, the composition and extension of their vegetal formations throughout the Holocene. Ninety-nine woody macroremains, 3 bark remains and 8 pinecones were located from eight sites between 875 and 1860 m above sea level, among which 15 radiocarbon dates were made. The taxonomic identification of two trunks found in Estrela allows us to document the local presence of Pinus cf. sylvestris ca. 6600 cal BP in this site. The same taxon also appears at the western end of Gredos between ca. 1700–2800 cal BP at approximately 1300 m. These remains expand the Holocene distribution of P. cf. sylvestris in the Central System known to date, both temporally and geographically. In parallel, the macroremains analysed document the composition of high mountain scrub (Cytisus type, Erica cf. arborea) in Béjar (ca. 1860 m), as well as mixed scrub-woodland formations in Gata (975–1180 m), which included deciduous Quercus , Betulaceae and Ericaceae. The presence of P. pinaster at ca. 6200 cal BP and 1180 m in this mountain range constitutes the earliest palaeobotanical evidence of this species recorded in Gata. The main results support the continuous persistence of plant formations in which P. sylvestris , P. nigra , and P. pinaster would have formed part throughout the Iberian Central System during the Holocene in a wide altitudinal range (1100–1840 m). • Above one hundred Holocene macrofossils from eight different sites were analysed. • Pinus sylvestris recently disappeared from the western Central System. • P. gr. sylvestris remained in Serra da Estrela until ˜6650 years ago. • First evidence of Pinus pinaster has been found in Gata ˜6200 years ago. • Betula , Quercus , Alnus and Ericaceae Holocene macroremains were found in Gata. [ABSTRACT FROM AUTHOR]