BEFESA

Sustainable development is defined as the "development that is capable of meeting existing needs without compromising the resources and possibilities of future generations"⁽¹⁾.

This is the most popular and most complete definition of sustainable development.

_{(1) Report by the World Commission on Environment and Development (Brundtland Commission): Our Common Future UN (11/12/1987), Chapter 2, Page 43.}

In order to provide a more specific definition, the following aspects should be highlighted:

• There should be no unreasonable loss of any natural resources: minerals, fuel, timber…
• There should be no significant damage done to natural systems: forests, animals, water, aquifers, air...
• There should be no significant deterioration to the social stability: large dams that force major populations to relocate, river diversions that create deserts over important expanses of terrain, large lakes that are dried up…

_{D. Pearce, A. Markandya and E. B. Barbier, Blueprint for a Green Economy (London, Earthscan Publications, 1989).}

According to the scientific community, there will be a substantial increase in the world’s population in the coming years, reaching some 8.0 billion people within 20 years, and 11.0 billion by 2050. This situation will have important consequences on the environment:

• Water scarcity. In 20 years’ time, 50% of the population could suffer from high costs.
• An increase in industrial and domestic waste levels.
• A significant increase in energy demand. This will not only create a problem in terms of how to meet this demand, but if the appropriate measures are not taken, it will lead to a significant increase in greenhouse gas emissions and the greenhouse effect.

It is therefore important to provide feasible solutions to each of these problems, including the climate changes.