Renewable energies (RE) generate value from the technological innovations, which allow increasing efficiency, lower investments costs, favoring the reduction of the final energy bill and energy dependence. Additionally, generates other social and economic benefits, generally not properly assessed. Domestic energy policy needs to assess them so as to shape this, enabling environmental benefits by maximizing its local social doles based on the development, production, installation and maintenance of RE technologies, increasing access to energy, reducing energy costs and resource conflicts, allowing to improve environmental quality. This research assesses the impact of new investments in solar and wind electricity generation capacity on the emission of greenhouse gases (GHG) and other harmful toxic gases such as SO2 or NOx, for the Central Region of Portugal. The main contribution is a global impact assessment, not only from the traditional perspective of the power generation planning, but also considering costs and benefits of economic and social aspects of the most relevant externalities. The first phase of the project assesses the impact of new solar and wind generation capacity investments on the GHG and other harmful emissions in the Central Region of Portugal, using a centralized planning model to be developed, based on the operation and investment costs of the generation units. The recent Portuguese National Plan for Energy and Climate (NPEC) objectives will be considered. This region has been chosen due to its relevance in the national energy sector and positive contribution to Europe's energy efficiency and RE commitments. For example, 70% of its final electricity consumption is based on renewable generation, while the national average is 59.1%. The second phase assesses the local effects of its most relevant externalities such as decreasing emissions, lowering electricity prices, decreasing energy dependence, new business model’s creation (such as RE commu...