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Shaping a secure and sustainable energy future may require a set of transformations in the global energy sector. Although several studies have recognized the importance of Electric Vehicles (EVs) for power systems, no large-scale studies have been performed to assess the impact of this technology in energy systems combining a diverse set of renewable energies for electricity production and biofuels in the transportation sector such as the case of Brazil. This research makes several noteworthy contributions to the current literature, including not only the evaluation of the main impacts of EVs' penetration in a renewable electricity system but also a Life-Cycle Assessment (LCA) that estimates the overall level of CO 2 emissions resulted from the EVs integration. Findings of this study indicated a clear positive effect of increasing the share of EVs on reducing the overall level of CO 2 emissions. This is, however, highly dependent on the share of Renewable Energy Sources (RES) in the power system and the use of biofuels in the transport sector but also on the credits resulting from the battery recycling materials credit and battery reuse credit. Our conclusions underline the importance of such studies in providing support for the governmental discussions regarding potential synergies in the use of bioresources between transport and electricity sectors. ; The researchers further like to acknowledge the financial support by the National Council for Scientific and Technological Development (CNPq), Brazil. This work has been also supported by FCT e Fundaçao para a Ciência e Tecnologia within the R&D Units Project Scope: ...

Ensuring the supply of affordable energy, improving energy efficiency and reducing greenhouse gas emissions are some of the priorities of the governments of several countries. The pursuit of these energy goals has triggered interest in the exploration and usage of Renewable Energy Sources (RES), which can be particularly appropriate for island systems as is the case of Cape Verde. This work proposes a generation expansion planning model for Cape Verde considering a 20 years' period. Different scenarios were analysed, each one representing a possible RES contribution for electricity production, reaching a 100% RES share. The results demonstrate that the increase of the RES in the system will lead to an increase of the total cost of energy. However, both CO2 emissions and external energy dependency of the country significantly decrease. The seasonality of the RES resources, and in particular of wind power is shown to be one of the most important challenges for the effective uptake of such a renewable power system. While the proposed model allowed already to present some useful scenarios, it becomes also evident the need to expand the analysis, and the paper concludes with directions for future research.

All rights reserved. Ensuring the supply of affordable energy, improving energy efficiency and reducing greenhouse gas emissions are some of the priorities of the governments of several countries. The pursuit of these energy goals has triggered interest in the exploration and usage of Renewable Energy Sources (RES), which can be particularly appropriate for island systems as is the case of Cape Verde. This work proposes a generation expansion planning model for Cape Verde considering a 20 years' period. Different scenarios were analysed, each one representing a possible RES contribution for electricity production, reaching a 100% RES share. The results demonstrate that the increase of the RES in the system will lead to an increase in the total system cost. However, a significant decrease in both CO2 emissions and external energy dependency of the country is projected. The seasonality of the RES resources, and in particular of wind power is shown to be one of the most important challenges for the effective uptake of such a renewable power system. A least-cost solution might be possibly achieved if storage technologies would be considered within the modelling approach (e.g. battery and Power-to-Gas technologies) which would also contribute to accommodate the Critical Excess of Electricity Production (CEEP). While the proposed model allowed already to present some useful scenarios, it becomes also evident the need to expand the analysis by using hourly data and taking into account the sector's integration (e.g. power, heat and transport). ; INCT-EN - Instituto Nacional de Ciência e Tecnologia para Excitotoxicidade e ...

There have been several challenges concerning the decisions and timing of new investments in the Brazilian power electricity generation due to irreversibility characteristics and uncertainty inherent in the sector, such as the volatility of electricity prices. Large hydropower plants are getting difficult to implement in the Brazilian generation sector, primarily due to environmental concerns and political pressure. Therefore, there has been an increasing focus on investments of small-scale hydropower plants (SHP). In this context, this paper analyses the use of Real Option (RO) theory for decision-making concerning the investment in SHP's in Brazil. This paper investigates the possibility for the entrepreneur of postponing its participation in the auctions proposed by the government. The deferral option can bring relevant value to the evaluation of SHP since the investor has the option to wait until more favorable conditions appear, e.g., better electricity prices or authorization. Therefore, the application proposed in this paper may be considered as a novel approach regarding the application of the RO theory. For this purpose, a real SHP of 7 MW of installed capacity was used as an investment case and it was assumed that the entrepreneur has the option to participate in the auctions in the next three years (2018 - 2020). A comparison of the results considering the traditional economic analysis (based on the discounted cash flows) is undertaken to evaluate the proposed approach. It can be concluded that the deferral option in participating in the auction can be considered a real option for investors and this time flexibility might bring financial advantages since the uncertainties are reduced. Furthermore, the methodology proposed in this paper has great potential to assess future SHP project evaluation and can be adapted to evaluate other power options. ; - ...