Energy for a sustainable world. (Environment and Development: A Global Commitment)

THE concept of sustainability is a highly complex one, particularly where energy matters are concerned. We can only hope to approach anything like absolute sustainability by the use of renewable energy resources such as hydro-electricity; but even hydro-electricity involves problems such as the silting up of dams or the secondary environmental damage dams can cause, which makes it less than a hundred per cent sustainable.

On the other hand, some fossil fuels, such as coal, are quite abundant and evenat their present rate of consumption will last for several centuries, when other sources of energy might become available.

The Report of the World Commission on Environment and Development (1987) defined sustainable development as development that "meets the needs of the present without compromising the ability of future generations to meet their own needs". And this, perhaps, contains the hint that we need to introduce the notion of "depletion rates" into any discussion of sustainability. This opens the way to the establishment of compromises between what is desirable in principle and what is practical in terms of the realities of everyday life. Such compromises are unavoidable when a choice has to be made between preserving resources and the needs of survival and development.

If energy use were to be considered in conformity with the strict definition of sustainable development, this would mean that man should rely exclusively on renewable sources or energy. This was the case before the industrial revolution, when fuelwood, used in a renewable fashion, was basically the only source of energy.

With population growth and increased demand for energy, however, exhaustible fossil fuels came into use and became the predominant energy source. In the industrialized countries today, fuelwood represents less than one per cent of total energy consumption, the remaining demand being met basicaly by fossil fuels--coal,

This is clearly an unsustainable form of development, since the depletion of existing reserves of fossil fuels is proceeding at a fast pace and will certainly "compromise the ability of future generations to meet their own [energy] needs."

Depletion, and eventual exhaustion, of stocks of fossil fuels are not the only problems. Their use entails other problems which affect the sustainability of the system in which we live--the emission of carbon dioxide and other gases is the major cause of atmospheric pollution and global warming and thus poses a threat to the way of life of future generations.