The most common definition of "energy" is "the ability or capacity to do work or to produce change." Forms of energy include heat, light, sound, electricity, chemical energy, and, according to the theory of relativity, mass.

Electricity, which is readily converted to light, heat, and (through motors) to mechanical energy again, is the most widely used form of energy in modern societies. One of its greatest advantages is that it is easily transmitted over long distances.¹ This report focuses on nuclear power's role in the generation of electricity.

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Energy Use Trends
(Excluding centrally-planned economies.)

Since World War II, oil has fueled most of the increase in international energy consumption, and it remains the world's most important energy resource. Worldwide, oil makes up almost half of the total energy used each year.²

Coal, which accounted for more than half of the energy used in the world in 1950, now represents only 20 percent of the global total. Its use declined during the 1960's, but has increased substantially since 1975.³

Natural gas and hydroelectric power consumption have grown steadily since 1950. Natural gas use in the West almost matches that of coal, and hyrdroelectric power's contribution to worldwide energy consumption now stands at approximately 8 percent.⁴.

Nuclear power began to make measurable contributions to the world's energy needs in the early 1970's, and by 1985 nuclear reactors generated about 6 percent of the energy consumed worldwide.⁵

Compared to future world energy contributions of oil, coal, natural gas and hydroelectric, nuclear power is expected to account for the smallest share of total energy use -- increasing from about 6 percent in 1985 to a projected 7.6 percent in 1995.⁶

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Energy Efficiency, Conservation, and Renewable Energy

Advances in technologies for the more efficient use of energy have helped reduce the consumption of oil and other fuels, especially over the past ten years,⁷ and at almost every utility in the United States, the advantages of utility-sponsored conservation programs are gaining acceptance as a management priority.⁸

Contributions to the world energy supply from renewable energy sources (including solar, biomass, wind, and geothermal) are projected to grow at a faster rate than any other energy sources between now and 2005. If this projection holds true, the share of total energy derived from all forms of renewable energy (including conventional hydroelectric plants which currently account for roughly two-thirds of all renewable energy used worldwide) will expand from 9 percent to 12 percent.⁹

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Nuclear Power and Electricity

Unlike oil, coal, and natural gas, nuclear energy is used almost exclusively for generating electricity.¹⁰ Approximately 20 percent of the world's electricity is now generated by nuclear reactors.¹¹ Coal's share of world electricity production is about 40 percent,¹² hydroelectric's is about 20 percent,¹³ oil's is between 8-10 percent,¹⁴ and natural gas' is about 10 percent.¹⁵

Nuclear energy is expected to be the fasted growing supplier of electricity worldwide between 1985-1990,¹⁶ while coal consumption by electric utilities is expected to grow at a moderate pace through 1995.¹⁷

Prospects for the future use of oil and natural gas to generate electricity are uncertain; they vary with oil and gas prices,¹⁸ and electricity demand.¹⁹ Most of the world's rivers with the best hyrdroelectric potential are already exploited, but small-scale hydroelectric projects should contribute to hydroelectric power's limited growth through 1995.²⁰

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Nuclear Power Trends

The United States currently leads the world in installed nuclear capacity.²¹ There are 109 commercial nuclear plants licensed to operate in the U.S.,²² producing more than twice as much nuclear power as France, the closest competitor. However, while nuclear power currently accounts for 16 percent of the U.S. electricity output, no new nuclear plants have been ordered in the U.S. since 1978 (compared to over 100 new plant orders across the world during the same period).²³ Since 1972, 117 U.S. nuclear plant orders have been canceled, and every project on which construction started after 1973 was eventually canceled.²⁴

France currently operates the world's most ambitious nuclear power program. Nuclear power supplies over 70 percent of France's electricity. Japan is now deploying new nuclear power plants at the highest rate in the world, with nuclear power already generating 27 percent of the country's electricity.²⁵

Other countries have adopted a go-slow approach to nuclear power, or have opted to abandon it altogether. In Sweden, voters approved a 1980 national referendum that called for the end of the country's nuclear reactor construction program and the closing of all of the country's nuclear power plants over the ensuing 25 years.²⁶ In the wake of the Chernobyl nuclear power plant accident in the Soviet Union, the Swedish government has responded to calls for accelerating the phase-out of their operating plants by establishing a commission to consider detailed phase-out plans.²⁷ Nuclear power currently supplies 42 percent of Sweden's electricity.²⁸

In Austria, Finland, Taiwan, and the Netherlands, plants under construction and/or plans to expand nuclear capacity have been either delayed indefinitely or canceled.²⁹ (For a select list of major adjustments to nuclear programs since 1980, click here. For a country-by-country list of percentages of nuclear-generated electricity, click here.)

As of June 30, 1987, 25 countries had nuclear power plants in operation, and 6 countries had plants either awaiting licenses, under construction or on order. 386 plants had been completed worldwide, and 175 additional plants were under construction.³⁰

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