Economia

The global financial crisis has brought severe impacts on the Portuguese economy. In this context, the Portuguese government has recently adopted harsh measures that will have deep impacts on peoples' lives. This paper discusses the influence of these measures on economic growth, social well-being, energy consumption as well as its impacts on the environment using a multi-objective linear programming model based on input–output analysis. Uncertainty is captured taking into account different model coefficient settings by means of interval programming tools.

Portugal is faced with important challenges concerning the definition of policies to achieve energy and environmental targets, taking also into account the economic and social issues. A multi-sectoral economy–energy–environment model has been developed to perform a prospective analysis of the changes in the economic structure and the energy system, as well as to assess the corresponding environmental impacts, providing decision support in policy making. This model is a multi-objective linear programming model that allows for the explicit consideration of distinct axes of evaluation, generally conflicting and non-commensurate, of the merit of distinct policies. The policy recommendations obtained are subject to the inherent uncertainty associated with the model coefficients and, therefore, they may not be robust in face of changes of the input data. The specification of less energy or carbon-intensive technologies is done by considering pollutant/energy coefficients defined as intervals. This analysis is crucial for understanding the role of technology in carbon mitigation efforts and other energy system planning settings, allowing to explore the effects of distinct policies on the total system costs, the fuel and technology mix, and the levels of greenhouse gases and other emissions.

Mathematical programming models for decision support must explicitly take account of the treatment of the uncertainty associated with the model coefficients along with multiple and conflicting objective functions. Interval programming just assumes that information about the variation range of some (or all) of the coefficients is available. In this paper, we propose an interactive approach for multiple objective linear programming problems with interval coefficients that deals with the uncertainty in all the coefficients of the model. The presented procedures provide a global view of the solutions in the best and worst case coefficient scenarios and allow performing the search for new solutions according to the achievement rates of the objective functions regarding both the upper and lower bounds. The main goal is to find solutions associated with the interval objective function values that are closer to their corresponding interval ideal solutions. It is also possible to find solutions with non-dominance relations regarding the achievement rates of the upper and lower bounds of the objective functions considering interval coefficients in the whole model.

In most real-world situations, the coefficients of decision support models are not exactly known. In this context, it is convenient to consider an extension of traditional mathematical programming models incorporating their intrinsic uncertainty, without assuming the exactness of the model coefficients. Interval programming is one of the tools to tackle uncertainty in mathematical programming models. Moreover, most real-world problems inherently impose the need to consider multiple, conflicting and incommensurate objective functions. This paper provides an illustrated overview of the state of the art of Interval Programming in the context of multiple objective linear programming models.

An economy-energy-environment (E3) multiple objective model based on the linear structure of inter-industry production linkages is presented. Axes of evaluation consistent with sustainable energy strategies, economic growth, social welfare and environmental friendliness are explicitly considered. The aim of this study is to provide decision-makers with a comprehensive model which allows assessing environmental burdens (global warming potential and acidification potential) with respect to changes in economic activities associated with distinct policy measures.

"An economy–energy–environment multiple objective model based on the linear structure of inter-industry production linkages is presented.Axes of evaluation consistent with sustainable energy strategies, economic growth, social
welfare and environmental friendliness are explicitly considered.The aim of this study is to provide decision-makers with a comprehensive model which allows to assess environmental burdens (global warming potential and acidification potential) with respect to changes in economic activities consistent with distinct policy measures."

In this paper an energy-economy planning model is developed, aimed at providing decision support to planners and decision makers in the study of the interactions between the energy system and the whole economy. For this purpose a multiple objective linear programming (MOLP) model is developed by using the coefficients of an input-output table, where the energy sectors as well as the relevant economic activity sectors are disaggregated. The results provided by the MOLP model with a set of data representative of the Portuguese situation are analyzed using the STEM interactive method.

In this paper a study is presented which is aimed at modelling the interactions of the energy system with the economy on a national level. For this purpose a multiple objective linear programming (MOLP) model is developed, which is based on an input-output (IO) table where the energy sectors as well as the relevant economic activity sectors are disaggregated. The results provided by the MOLP model with a set of data representative of the Portuguese situation are analyzed using the TRIMAP interactive environment.

Portugal is a member-state of the European Union (EU), with a GDP at market and current prices of 171 858, 5 *106 € in 2011, a small peripheral economy when compared to the EU-27 average GDP of 468 534, 1 *106 € in 2011 [1]. Concurrently, it is one of the highest external energy dependent European countries (83.1% in 2008), contrasting with the EU-27 average energy dependency (53.8%), mainly because of Portugal’s lack of primary energy sources [1]. Nevertheless, Portugal has been in the forefront of energy policy making, having to comply with several ambitious targets. These overall goals may be seen as a consequence of the set of European Directives in the energy field (already transposed into national law), which have their grounds on three broad pillars: competitiveness, security of supply and sustainability. In this chapter we aim at systematizing and revisiting the energy liberalization process in Portugal, covering the evolution of the regulatory ruling, the tariffs setting, the role of the Iberian Electricity Market and the diversity of the most up to date legislative framework, with a special focus on the renewables field, in the context of an economic recession period. Finally, it will be our purpose to shed some light on the legacy costs which are to be imposed on the next generation of consumers and citizens in a near future, due to the utmost goal of building a true competitive energy market.

"Although sustainable development has been accepted as an environmental issue, mainly focusing on the integration of environmental and economic dimensions, the social dimension has also been generally recognized as an equal part of sustainable development. In this context, the need for further integration of economic and social policies requires improved integration of social and economic statistics.
In the last years Portugal became a world leader in the deployment of renewable energies. The Portuguese national energy strategy 2020 (NES 2020) aims to reinforce Portugal’s leadership in sustainable energy and to attain the ambitious goals set in the government programme, namely consolidating the renewable energies cluster in Portugal, which will represent by 2020 a Gross Added Value of 3800 million Euros and 100000 new jobs beyond the current 35000 jobs and further developing the industrial cluster related with energy efficiency, creating 21000 new jobs.
The main purpose of this paper is to perform a prospective study and to discuss the various factors that influence the analysis of sustainable development and its impact on a particular and critical social dimension: the employment, mainly focusing on the renewable energy jobs case by means of a multiobjective Input-Output model, based on current data availability."

"Following the EU trends, energy has been at the top of national agenda in Portugal and the country has been quickly emerging as a “green” trendsetter due to its determination to reduce its dependence on imported fossil fuels by channelling its wind, solar, and hydropower resources - even though such clean energy transitions have come at substantial financial costs.
In the context of the so-called Climate Change and Energy package for 2020 by the European Commission, Portugal has to meet a target of 31% regarding the share of renewable sources on gross final energy consumption, including 10% in transportation, to meet the targets imposed on greenhouse gas emissions, energy efficiency and use of renewable energy. The National Renewable Energy Action Plan (NREAP), prepared and written on the basis of the Commission Decision of 30th of June 2009, which provides for a template for national renewable energy action plans in the Directive 2009/28/EC, includes measures for achieving renewable energy targets and an overview of all policies and measures to promote the use of energy from renewable sources. In this context, one of the most promising renewable energy technologies is photovoltaic (PV) technology (i.e. devices that transform solar energy into electricity). Photovoltaic is a truly elegant means of producing electricity on site, directly from the sun, without concern for energy supply or environmental harm. These solid-state devices simply make electricity out of sunlight, silently with no maintenance, no pollution, and no depletion of materials. The purpose of this paper is to provide an integrated analysis of photovoltaic systems, based on outputs and results from energy/environmental analysis, and other tools such as financial appraisal will also be performed in order to assess how these systems perform on the building sector level or when compared to other energy technologies."

"Renewable energy is playing an increasing role in energy mixes around the world, including Europe, which is aiming for a target of 20% renewable energy by 2020. Portugal is at the forefront of the European intention, with a 31% target. The advantages of the application of renewable energy policies are widely accepted to include a decrease in greenhouse gas emissions and an improvement in energy security. In many cases job creation is also touted as a benefit but this claim stands on an uncertain footing.
Amongst the variety of methodologies, analytical studies using extensive surveys seem to be more appropriate for regional studies while linear simulations, either in the form of input-output (I-O) analysis or, in recent years, social accounting matrix (SAM) multiplier analysis appear to better suit national and international studies. This paper offers an assessment of the impact of Portuguese ‘green’ energy policies on the employment level departing from a system of symmetric input-output tables recently built for Portugal by the Department of Foresight and Planning.
"

"A sustainability model offers the framework for differentiated analyses, which go beyond economic factors and include environmental and social effects of different policy measures.
These models enable gaining knowledge about possible impacts of different policy measures on economic, social and environmental aspects. In particular, multiple objective linear programming models based on the linear inter/intra industrial linkages of production (that is input-output analysis) can be used to study the interactions between the four main pillars of sustainable development: economy, energy, social and environmental concerns. These models allow assessing the environmental and social impacts resulting from changes in the level of the economic activities associated with distinct policies, through the explicit consideration of distinct axes of evaluation of the merits of different policies that are modeled as objective functions: Maximization of Gross Domestic Product as proxy for assessing the economic
growth, maximization of the level of employment as a measure of social well-being, minimization of the energy imports as a way of minimizing the energy dependency of the country, and minimization of GHG emissions in order to account for the environmental impacts of the economic activities. In this context, the input-output framework provides a tool for determining the number of jobs created, but as the body of literature concerning sustainability and employment grows it has become increasingly obvious that there is no
consensus on how best to measure job creation, especially for particular technologies. This paper presents a discussion of the various factors that influence the analysis of sustainable development and its impact on the employment level."

"The Global Financial Crisis has brought severe impacts on the Portuguese economy. In this context, the Portuguese government has recently adopted harsh measures that will have deep impacts on peoples’ lives. This paper discusses the influence of these measures on economic growth, social well-being, energy consumption as well as its impacts on the environment
through the use of a multi-objective linear programming model based on input–output analysis, taking into account different coefficient settings by means of interval programming tools. "

A multi-sectoral economy-energy-environment model is proposed to perform a prospective analysis of the changes in the economic structure and the energy system resulting from different policies, as well as to assess the corresponding environmental impacts, providing decision support in policy making. The model is a top-down macro-economic multi-objective model, which allows taking into account the energy carriers associated with primary supplies, conversion and transformation processes. The demand for energy services is disaggregated by economic sectors and may be disaggregated by specific functions within a sector. The model allows to explore the effects of new less energy-intensive or carbon-intensive technologies on the total system costs, changes in fuel and technology mix, and the levels of greenhouse gases and other emissions. This is done in the model framework by considering pollutant/energy coefficients defined as intervals, which capture the uncertainty associated with new processes and/or technologies. This type of analysis is of outstanding importance for understanding the role of technology in carbon mitigation efforts and other energy system planning studies at a macro level.

"Multiple objective programming models allow for the explicit consideration
of distinct axes of evaluation, generally conflicting and non-commensurable, of the merit of solutions. In particular, multiple objective linear programming (MOLP) models based on the linear inter/intra industrial linkages of production can be used to study the interactions between the economy, the energy system and the environment. These models allow assessing the environmental impacts resulting from changes in the level of the economic activities sustained by distinct policies. However, the uncertainty associated with the model coefficients, namely those derived from Input-Output
(I-O) analysis, may lead to conclusions that are not robust regarding the changes of the input data. In this context a MOLP model based on I-O analysis with interval coefficients is proposed, which allows assessing the impacts of distinct policies on the economy, the energy system and the environment, based on the levels of activity of the economic sectors."

"In most real-world situations, problems are characterized by multiple, conflicting and incommensurate axes of evaluation. Moreover, in most real-world problems the available data is inexistent or scarce, difficult to obtain or estimate, the system is subject to changes, etc.
Therefore, mathematical programming models for decision support must bear, besides multiple and conflicting objective functions, the uncertainty associated with the model coefficients. There are several approaches to tackle uncertainty in mathematical programming models. In this context, interval programming possesses some interesting characteristics because it does not
require the specification or the assumption of probabilistic distributions or possibilistic distributions. The interval programming approach assumes that the ranges of variation of some (or all) coefficients which allow specifying a model are known. Interval programming methods have been used to tackle specific issues in multiple objective linear programming (MOLP): some deal with uncertainty in the objective functions, others handle uncertainty both in the objective functions and in the RHS of the constraints and others deal with uncertainty in all the coefficients of the model (see an illustrated overview of these methods in [5]).
In this paper we propose an approach for MOLP problems with interval coefficients that deals with the uncertainty in all the coefficients of the model."

An economy-energy-environment (E3) multiple objective model based on the linear structure of inter-industry production linkages is presented. Axes of evaluation consistent with sustainable energy strategies, economic growth, social welfare and environmental friendliness are explicitly considered. The aim of this study is to provide decision-makers with a comprehensive model which allows assessing environmental burdens (global warming potential and acidification potential) with respect to changes in economic activities consistent with distinct policy measures.

An economy-energy-environment multiple objective model based on the linear structure of inter-industry production linkages is presented. Axes of evaluation consistent with sustainable energy strategies, economic growth, social welfare and environmental friendliness are explicitly considered. The aim of this study is to provide decision-makers with a comprehensive model which allows assessing environmental burdens (global warming potential and acidification potential) with respect to changes in economic activities consistent with distinct policy measures.

"In most real-world situations, the coefficients of decision support models are not exactly known. In this context, it is convenient to consider an extension of traditional mathematical programming models incorporating the intrinsic uncertainty, without assuming the exactness of the model coefficients.
Interval programming is one of the tools to tackle uncertainty in mathematical programming models. This paper provides an overview of the state of the art of Interval Programming in the context of multiple objective linear programming models, paying special attention to the optimizing approach."