2 Energy and environmental issues of smart buildings

In every country in the world, the built environment normally constitutes more than half of the total national capital investment and construction represents as much as 10 % of GNP (CICA 2002). Energy consumption defines the quality of urban life and the global environmental quality of cities. Energy is linked with all aspects of development and has a tremendous impact on the well being of urban citizens, health, education, productivity, economic opportunities, etc. Unfortunately, the current situation on energy supply and consumption is extremely unfair and wide disparities exist between the developed and the developing world. Almost one third of the world’s population has no access to electricity while the second third has very poor access (WEHAB 2002). Although 75 million people gain access to electricity on an annual basis, the total number of people lacking electricity does not change (Albouy and Nadifi 1999). It is characteristic that the richest nations of the world consume almost 25 times as much energy per person as the poorest people (Albouy and Nadifi 1999). Energy is the most important engine to improve the quality of life and fight poverty. Given that by 2020 almost 70 % of the world population will be living in cities and 60