Throughout most of North America, Western Europe and even the Soviet Union, people are rejecting the expansion of nuclear power. Unless the technology is completely revamped and there is a complete turnabout in public attitudes, both of which are increasingly implausible, the necessary scale of expansion is impossible. Improved energy efficiency can have a much larger and more immediate impact on carbon emissions and global warming. Without these measures, carbon emissions would have reached 1.5 billion tons annually. Another 300 million tons of carbon were avoided by efficiency improvements in other countries.
Similar gains are possible in the future using already available technologies.
Shifting to more fuel-efficient transportation can sharply reduce carbon emissions. Projections based on recent trends would have these emissions nearly doubling by 2010. However, if a combination of improved mass transit, greater use of bicycles for short trips, and a carbon tax kept the world fleet to 500 million cars in the year 2010, and if these vehicles averaged 50 miles to the gallon rather than the current 20, automobile carbon emissions would fall to 273 million tons, half of what they are today. Carbon emissions can also be lowered by improving the efficiency of electricity-using devices. This accounts for 28 percent of the 1.5 billion tons of global carbon emissions coming from fossil fuels.