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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 ...

The mining sector in Brazil has grown in the last decades contributing in an expressive form to the economic growth of the country. However, this progress has also contributed to the increase of environmental impacts brought by the mining industries include puts in evidence the need to define strategies well suited to deal with the particularities of each process or company. The main goal of this research was to develop a conceptual model matching environmental strategies with the sustainability dimensions focusing on the mining sector. The model was validated through two empirical approaches, including a Delphi study and a case study. From the Delphi study 28 environmental strategies were identified and classified in a work which is deemed to be relevant for companies targeting sustainability objectives and dealing with different environmental objectives. The case study addressed a large mining company located in the State of Paraiba in Brazil and showed both the relevance of the proposed model to justify the selection of the environmental strategies and the determinant factors for this selection. Endogenous factors are considered to be decisive for the organization to select and implement these strategies and with the exception of environmental legislation, exogenous factors have not exerted an overall important pressure on the organization.

The mining sector in Brazil has grown in the last decades contributing in an expressive form to the economic growth of the country. However, this progress has also contributed to the increase of environmental impacts brought by the mining industries include puts in evidence the need to define strategies well suited to deal with the particularities of each process or company. The main goal of this research was to develop a conceptual model matching environmental strategies with the sustainability dimensions focusing on the mining sector. The model was validated through two empirical approaches, including a Delphi study and a case study. From the Delphi study 28 environmental strategies were identified and classified in a work which is deemed to be relevant for companies targeting sustainability objectives and dealing with different environmental objectives. The case study addressed a large mining company located in the State of Paraiba in Brazil and showed both the relevance of the proposed model to justify the selection of the environmental strategies and the determinant factors for this selection. Endogenous factors are considered to be decisive for the organization to select and implement these strategies and with the exception of environmental legislation, exogenous factors have not exerted an overall important pressure on the organization.

Some three fourths of electricity generation in Brazil come from renewables. Most of it is supplied by hydro, complemented by biomass-fueled thermal power plants and wind, while solar is still irrelevant. However, in the medium and long terms, a strong growth is expected for wind and solar in the country. Solar and wind resources are variable in time, partially unpredictable and cannot be dispatched to meet the load. These characteristics require system flexibility, which is the capacity of the power grid to adapt to different supply and demand patterns. Given that most thermal plants are not designed for a large frequency of operating cycles, renewables penetration may result in higher maintenance and operating costs, increased fuel consumption and reduced lifetime. Furthermore, some units might be called out-off-merit to maintain voltage and frequency levels. This paper presents preliminary results on the ability of thermal units to provide flexibility to the country´s grid, through an analysis for the Northeast region bounded by transmission constraints among 65 nodes (out of 196 nodes along the country). Results show that the power sector in Brazil might not be well equipped to deal with high penetration rates of variable renewable energy sources, with impacts on the capacity factor, and on the efficiency, of thermal power plants in the country. They also reveal that while wind energy increases the need of ramping capabilities, solar has greater impacts on the number of starts and shutdowns of conventional units. ; This research was supported by a Marie Curie International Research Staff Exchange Scheme Fellowship within the 7th European Union Framework Programme, under project NETEP- European Brazilian Network on Energy Planning (PIRSES-GA-2013-612263). The authors would also like to express their gratitude to the Coordination for the Improvement of Higher Education Personnel (CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior) for the essential support given for this work to be carried ...

The topic Sustainable Development has brought a wide discussion across a number of sectors in our society, namely in Power Systems. Given the need to address other concerns than the economic ones, decision makers must take into account the rationale that lies beneath strategic choices, such as investing in generation technologies using renewable energy or rather doing business as usual and installing fossil fuel power plants. In this paper logic models were used as a decision-aid supporting tool, with the aim of contributing to the assessment of the possible impacts of different power plants in terms of sustainable development. The analyzed electricity generation technologies were grouped in thermal, renewable energy sources (RESs) and nuclear. The literature review fed the construction of three relational diagrams to allow the visualization of environmental, social and economic causes and effects of the three groups of technologies. Departing from these initial diagrams a set of interviews with experts was conducted to enrich and validate the logic models. The results of the literature review and of these interviews allowed to conclude that the use of RES has wider positive social impacts on the long run, despite their short-term higher costs compared to the traditional groups (nuclear and thermal). These logic models revealed to be a useful tool providing a valuable starting approach for an Impact Assessment of the ongoing change that power systems have been going through. ; This work was financed by the QREN – Operational Programme for Competitiveness Factors, the European Union – European Regional Development Fund and National Funds – Portuguese Foundation for Science and Technology, under Project FCOMP-01-0124-FEDER-011377 and Project ...

A Multi-Criteria Decision Analysis (MCDA) tool was designed and used to support the evaluation of different electricity production scenarios. The MCDA tool is implemented in a user-friendly Excel worksheet and uses information obtained from a mixed integer optimization model, to produce a set of optimal schemes under different assumptions. Given the input, the MCDA allowed ranking different scenarios relying on their performance on 13 criteria covering economic, job market, quality of life of local populations, technical and environmental issues. The MCDA tool was used by a group of experts and academics with background in economics, engineering and environment. Regarding the totality of results, both the most and least expensive scenarios ranked first the same amount of times. These scenarios were, respectively, "Coal", relying mainly in new coal power plants and "Maximum Renewable", relying mainly in new wind and hydro power facilities. The opinions were divided towards these two solutions with different fundamental characteristics: "Maximum Renewable" with costs higher than "Coal" but leading to substantial reduction of the external energy dependency. Sensitivity analysis suggests that, although the costs are regarded as the most important criterion, those who had different rankings in their preferences have different attitudes towards other criteria. ; This work was financed by: the QREN Operational Programme for Competitiveness Factors, the European Union e European Regional Development Fund and National Funds e Portuguese Foundation for Science and Technology, under Project FCOMP-01- 0124-FEDER-011377 and Project ...

Life Cycles of both products and services significantly consume renewable and non-renewable resources across a worldwide scale. Thus, eliciting an enormous environmental impact, that is known to disproportionately instigate crises into the socio-economic and political domains of our civilization. Therefore, Creation of Shared Value and Corporate Social Responsibility (CSR) have been considered by Policy makers, Public and Private Institutions. In addition to Corporate Philanthropy, CSR practices also encompass a wide spectrum of activities, including Stakeholder safety/welfare, designing sustainable products and ecological restoration to name a few which are ascertained to capital and knowledge intensive in nature. Therefore, this paper primarily structures the scope of CSR and proposes a mechanism for trading Corporate Social Responsibility credits in order to incentivize stakeholder centered business practices. Furthermore, the CSR credits trading methodology would entail similar mechanisms used by its remotely successful predecessors namely, tax incentives, tradable credits/certificates and flexible mechanisms for implementing sustainable projects. The CSR credits trading methodology is envisioned to entail a more holistic approach towards overall Sustainability when compared to Carbon Offsets/Renewable Energy Certificates which are more focused towards reducing the environmental footprint. ; The author acknowledges the contribution of MIT Portugal Program, University of Minho and Fundação para a Ciência e Tecnologia (FCT), Portugal (Foundation Of Science and Technology, Portugal) for the scholarship grant SFRH / BD / 33794 / ...

The increasing uncertainty surrounding the electricity generating sector has implications on the forecasting accuracy and makes sensitivity analysis an essential tool for electricity power planning. The fuel price volatility and the emissions trading schemes represent major sources of uncertainty, as the relative economic interest of thermo power plants and of renewable energy sources largely depends on these two factors. In this paper, an electricity planning model will be used to analyse both these aspects, identifying the relative importance and sensitiveness of the optimal electricity power plans to changes on these parameters. ; QREN – Operational Programme for Competitiveness Factors, European Union – European Regional Development Fund and Portuguese Foundation for Science and ...

This paper focus on the assessment of the social dimension of electricity planning, resourcing to participative methodologies. A guide for interviewing power systems experts, covering a wide range of themes is presented. The guide focus on evolution of electricity consumption and supply according to each type of technology, driving forces among emerging technologies, energy policy, the relevance of sustainable development among institutions and markets and, finally, a first impression on the relevance of social impacts for candidate technologies. The main aim of the methodology is to gather discourses among experts and try to understand the connection between narratives and their consequences on the best scenarios under the social point of view. Therefore, the interview uses both uantitative and qualitative questions. The former are used for creating electricity generation scenarios within a 10 year range, while the latter aim at gathering each position's underlying explanations, which will be useful for cluster analysis in future work. The results presented in this paper refer to interviews which took place among the members of the working group of the project "Sustainable Electricity Power Planning". ; This work was financed by: the QREN – Operational Programme for Competitiveness Factors, the European Union – European Regional Development Fund and National Funds- Portuguese Foundation for Science and Technology, under Project FCOMP-01- 0124-FEDER-011377 and Project ...

The topic Sustainable Development has brought a wide discussion across a number of sectors in our society, namely in Power Systems. Given the need to address other concerns than the economic ones, decision makers must take into account the rationale that lies beneath strategic choices, such as investing in generation technologies using renewable energy or rather doing business as usual and installing fossil fuel power plants. In this paper logic models were used as a decision-aid supporting tool, with the aim of contributing to explain the connection between building a given power plant and assessing its possible impacts in terms of sustainable development. All the electricity generation technologies were grouped in thermal, renewable energy sources (RES) and nuclear. The literature review fed the construction of three technology generation groups inference and relational diagrams to allow the visualization of environmental, social and economic causes and effects. The results of the literature review and of a set of interviews with experts, based on the diagrams, allowed to conclude that the use of RES have wider positive social impacts on the long run, despite their short-term higher costs compared to the traditional groups (nuclear and thermal). ; This work was financed by: the QREN – Operational Programme for Competitiveness Factors, the European Union – European Regional Development Fund and National Funds- Portuguese Foundation for Science and Technology, under Project FCOMP-01-0124-FEDER-011377 and Project ...

This paper overviews previous research addressing the inclusion of the, social dimension of sustainable development on power systems planning. Consequences of the recent energy policies and strategies are already being felt in, developed countries' power systems, with the integration of rising quotas in renewable, energy technologies. However, while the tools that aid decision making on power, planning show that economic and environmental issues are easily quantifiable and thus, modeled, social concerns have been addressed in a less extensive and more, subjective way, implying in most cases expert participation on multi-criteria decision aid, techniques. A survey of recent papers providing public perceptions on electricity, generation technologies and projects is presented. These papers were chosen and, reviewed in order to present a representative array of methodologies that are used to, assess social acceptance of technologies. According to some of the reviewed papers, this issue is suggested to be fundamental to increase project success. As a conclusion, stands the fact that further discussion is still needed in order to achieve solid, agreement, among experts, over what are the positive and the negative drivers to, social sustainability; otherwise models will not be able to translate reality and improve it, under this point of view. ; This work was financed by: the QREN – Operational Programme for Competitiveness Factors, the European Union – European Regional Development Fund and National Funds - Portuguese Foundation for Science and Technology, under Project FCOMP-01-0124-FEDER-011377 and Project ...

In a way to reduce the external energy dependence, increasing also the investments in renewable energy sources and aiming for the concretization of the European renewable objectives, the Portuguese government defined a goal of 5100 MW of installed wind power, up to 2012. If the drawn objectives are accomplished, by 2010 the wind power share may reach values comparable to leading countries like Denmark, Germany or Spain. The Portuguese forecasts also indicate a reinforcement of the natural gas fired generation in particular through the use of the combined cycle technology, following the European tendency. This analysis sets out to evaluate the total generating cost of wind power and CCGT in Portugal. A life cycle cost analysis was conducted, including investment costs, O&M costs, fuel costs and external costs of emissions, for each type of technology. For the evaluation of the externalities ExternE values were used. The results show that presently the wind power production cost is higher than the CCGT one, at least from the strictly financial point of view. CCGT costs increase significantly when charges for externalities are included. However, they only reach levels higher than the equivalents for wind power for high externality costs estimations. This partially results from the low load factor of the wind farms in Portugal and also from the lowemission levels of the gas fired technology used in the comparison. A sensitive analysis of the technical and economical parameters was also conducted. Particular attention was given to the natural gas prices due to the possible increase over time. The fuel escalation rate is the parameter that has larger effects on the final costs. It was verified that the total cost of wind plant is more influenced by the load factor than the total cost of ...