The issue of energy has two main aspects: type of energy used and amount of energy used. Sustainable approaches to energy supply are based on nonnuclear, renewable energy sources and more effective use of energy, through either improved technology or reduced energy consumption.
The environmental consequences of today’s energy policies are potentially catastrophic. The global warming caused by burning fossil fuels will disrupt thousands of kilometres of heavily populated and productive tropical coastline, as well as causing major changes in agroecological zones in both temperate and tropical areas. Ecologists are concerned that natural ecosystems will not be able to adapt rapidly enough to these changes through migration of plant and animal species, since the climate has not changed this rapidly previously. The ability of human societies to adapt to these changes is an open question.
The burning of fossil fuels also causes acid rain, contributing to the death of large areas of forest in Europe. Toxic heavy metals originating from fossil fuels or released under acid soil conditions (primarily cadmium, zinc and lead) are also found in disturbingly high concentrations in soils and vegetation in many places in Europe. The risks associated with nuclear energy are also great, as illustrated by the Chernobyl accident. It would be ironic if, in our efforts to reduce acid rain and the greenhouse effect, we shifted to nuclear power, which may pose an even greater environmental threat.
The answer lies partly in development of renewable energy sources such as biomass, methane, sun, wind, waterfall and wave power. The other part of the solution lies in using less energy and getting more out of each unit of energy (increased energy efficiency). In order to stabilize the CO2 concentration in the atmosphere, CO production must be reduced by 60-70 per cent in the developed countries. Through improved energy efficiency, choice of energy source and new technology some of this reduction can be achieved. The rest will have to be achieved by cutting down on unnecessary consumption and a reduction in standard of living measured in terms of material consumption. However, quality of life need not necessarily be reduced – in fact; it may increase because of better physical and mental health.