Extract

During the first decade of the twenty-first century, the world has become aware of the environmental impact associated with the technological, social and economic development of humankind over the last two centuries (Ferrao, 2009). The main international debate has focused on the influence of greenhouse gas (GHG) emissions on global warming and climate change, as this became one of the main drivers for global environmental awareness. The environmental impact of human activity is diverse and can be measured in multiple dimensions with specific metrics. A very simple form of providing a global assessment of the environmental impact on earth is the ecological footprint. The ecological footprint is a measure of the amount of biologically productive land and sea area needed to regenerate the resources that the human population consumes – food, energy, water and so on – and to absorb and render harmless the corresponding waste. Despite its limitations, this measure shows that in 2009, humanity’s total ecological footprint was estimated at 1.4 planet Earths using data from 2006 (Global Footprint Network, 2009). This very simple metric shows that we already need more land area than the one available on the planet to maintain current human activities, which illustrates the unsustainability of the current development paradigm, fundamentally based in economic growth. The world therefore faces the challenge of designing and implementing a new economic and social development paradigm that allows for the developing regions to extend their welfare provision in a more environmentally friendly way. Since energy supply, transformation and consumption is one of the development dimensions with a higher environmental impact (ibid.), this requires the emergence of sustainable energy systems, which can be defined as an adequate set of energy technologies and demand-driven services that lead to a more efficient use of natural resources.