ABSTRACT

Nuclear Power :This paper deals with comparative assessment of the environmental and health impacts of nuclear and other electricity generation systems. The study including normal operations and accidents in full energy chain analysis. The comparison of the environmental impacts arising from the waste management cycles associated with non emission waste are also discussed. Nuclear Power while economically feasible and meeting 17% of the world’s demand for electricity is almost free of the air polluting gases that threaten the global climate. Comparing nuclear power with other sources for electricity generation in terms of their associated environmental releases of pollutant such as SOj, NOX, COj, CH< and radioisotopes, taking into account the full fuel chains chains of supply option, nuclear power will help to reduce environmental degradation due to electricity generation . activities. In view of COj emission, the ranking order commences with hydro, followed by nuclear, wind and photovoltaic Power Plants. CO* emissions from a nuclear power plant arc by two orders of magnitude lower than those of fossil fueled power plants.

A consequent risk comparison between different energy sourceshas toinclude at phases of the whole energy cycle. Coal mines accidents have resulted in several 1000 acute deaths over the years. Later fatalities have never been estimated. Then came hydropower, also resulting in many catastrophes and losses of human lives. Followed*oil and gas energy industry, its tribute in acute fatalities is expressed- in more than 1000 lifes lost. No estimate is available concerning later fatalities, latest in the list is commercial nuclcarcncrgy, badly illustrated by the Chernobyl accident resulting officially in 31 acute fatalities, 145 latent fatalities, and 135000 evacuated individuals. The paper offers some findings and conclusions on the role of nuclear power in protecting the global environment Key words: Full chain-Energy Systems — Health — Environmental Impact – Comparative Assessment THE ROLE OF NUCLEAR POWER Nuclear Power can play an important role for the sustainable of energy. The resources base is large. Current estimates are that uranium resources will last some 400 to 500 years at the present rate of use. This resource base could furthermore, last some 50 times longer if breeder reactors were introduced {GTDC, 1995]. 291 The fossil fuels such as coal, petroleum, natural gas and oil shale have made and are still making great contribution to the progress of human society (Fig. 1), however they are all non renewable energy sources.

In addition they have limited reserves and uneven geographical distribution. It is estimated that the exploitable reserve of coal of the world is about 760 billion tons, petroleum 95.8 billion tons and natural gas about 9800 billion cubic meters. If calculated at the current rate of consumption, there will be decades of consumption, for the proven reserves of petroleum and natural gas and hundreds of years for coal. A total of 443 nuclear power plants are currently operating in 32 countries around the world, During 1996, construction of three new nuclear reactors started bringing the total number of nuclear reactors reported as being under construction to 35 in 14 countries world wide in 1996, total nuclear generated electricity grew to 2300 TWh.

This is more than the world’s total electricity generation 1912 TWh – from all sources in 1958. Overall nuclear power plants provided approximately 17% of the world’s electricity production in 1996. (Fig.l), Cumulative worldwide operating experience from civil nuclear reactors at the end of 1996 was over 8135 years, 18 countries relied upon nuclear power plants to supply at least a quarter of their total electricity needs. Nuclear energy has played a major role in reducing the world’s use of oil for electricity generation over the past two decades. Based on an evaluation of all fuels (coal, oil and natural gas) that would have been used to generate electricity if nuclear energy plants had not been built, from 1973 – 1989, nuclear energy displaces the burning of a cumulative total of 15.5 billion barrels of oil world wide. Oil generated less than 10% of the world’s total electricity in the 1990’s compared to more than 25% in 1973. Advanced designs are been developed for all types of reactors.

The main goals of the designers and manufactures are to: improve the economics of nuclear power, reduce the residual risk of accident, reduce the emissions and residuals, including radioactive waste from routine operation of nuclear facilities, expand the resource base and broaden the range of applicability of nuclear power. In an increasingly competitive-and international global energy market, a number of key factors will affect not only the energy choice but also the extent and manner in which different energy sources are used. These include: optimal use of available resources; reduction of overall costs; minimizing environmental impacts; convincing demonstration and safety; and meeting national and global policy needs. For nuclear energy and other options these five factors will determine the future of energy mix and strategies, at the national and global levels.

ENERGY DENSITY COMPARISONS (FUEL AND LAND REQUIREMENTS)

The quantity of fuel used to produce a given amount of energy – the energy densitydetermines in a large measure the magnitude of environmental impacts as it influences the fuel extraction activities, transport requirements, and the quantities of environmental releases and waste. The extraordinary high energy density of nuclear fuel relative to fossil fuels is an advantageous physical characteristic [IAEA, 1997}.