According to Charles Berb [13], the largest losses of thermodynamic availability (free energy) occur in combustion, heat transfer, and consumers' equipment and practices, which last leads us to the matter of the social efficiency of energy use. Social efficiency differs from technical efficiency. The technical or machine efficiency of the automobile changes very little when five people are riding instead of one, but its social efficiency changes a great deal. The thermal efficiency of electric lights being used by students in a college dormitory may be precisely the same as that of electric lights being used by gamblers in a Las Vegas casino, but one might argue that the social efficiency differs. Using an automobile for two trips to the supermarket where one trip would have sufficed is socially inefficient because it wastes a nonrenewable fuel, it exposes the occupants of the vehicle and the vehicle itself to unnecessary risk, and it wastes the time of the driver [14].

Much of the social inefficiency of energy use in the industrialized world is the result of careless habit, hardened by the availability of cheap energy: rising costs may change those habits, as well as the wasteful practices in industry and commerce. The contrast between Sweden and the United States in the economic efficiency of energy use reflects a difference in social efficiency. Sweden, with a per capita income not much less than that of the United States, uses half as much energy per person [15]-despite a climate that requires more energy for heating and lowers the operating efficiency of automobiles and trucks. The greater efficiency of the Swedes is due to an organization of society and an attitude toward thrift and waste that promote the efficient use of energy and materials. Small cars, well-developed public transport, fewer cars per thousand persons, compact towns and cities, and an awareness of conservation result in a much lower energy consumption than in the United States where heavy cars, inadequate mass transport, expensive use of air carriers, sprawling cities, and a throwaway economy have inflated the consumption of energy.

Some of the energy waste in the United States is enforced by the laws of the land. Laws, for example, restricting the kinds of goods that may be carried by some trucks and specifying the trucks that may carry them result in the increased mileage of trucks running empty or partly loaded. The laws that prevent loaded trucks from using the shortest distance between two points encourage a waste of time and energy. The federal government is committed to encouraging and protecting competition even when that competition causes scarce resources to be wasted, as is the case when two large airplanes fly the same route, perhaps only minutes apart, each with fewer than half the passengers it could carry. Each time such things happen, a heavier burden is laid upon those who will come after us and will not have the bounty of cheap fossil energy.

Much energy could be saved by recycling [16]. About half the energy used in industry goes into mining and processing raw materials taken from the earth because very few resources come out of the ground ready for use. Most of the energy used is devoted to crushing and grinding ores and smelting concentrates. These two energy-devouring steps are not necessary if one can simply remelt used aluminum, copper, steel, and lead objects. The energy required to melt a metal is

much less than the energy required to smelt its concentrated ore and to refine the impure product of the smelter.

Since in most of their uses metals are neither "consumed" nor widely dispersed (lead in gasoline and titanium in paint are exceptions), the potential energy savings make recycling attractive. Recycling also lowers the pressure on diminishing reserves of nonrenewable resources. The main problem in recycling is the cost (whether measured in kilocalories, manhours, or dollars) of separating and collecting the used objects. As the costs of primary metals (those obtained from ores) rise, more attention will be paid to economic ways of increasing the amount of secondary metal (that recovered from scrap) going to the melting furnace. Metal recycling could be increased in several ways: objects, machines, and structures could be designed so that the metallic elements can be easily separated from the rest; the dispersive use of metals could be reduced as much as possible, for instance, their use in nonreturnable containers; incentives could be established for returning disused metallic objects such as junked automobiles; separation and recovery plants could be developed at municipal garbage dumps. The amount of energy required to produce a ton of copper from copper ore or of any other metal from its ore rises sharply as lower grades of ore are mined [17]. This fact in itself, were energy costs to remain constant, would place a limit on the economic exploitation of ores. But energy costs are rising and probably will be yet higher in the future, and thereby the economic limits of ore bodies will shrink and the need to use metals efficiently and to recycle them will become more pressing.

Substances other than metals can be recycled. Glass and paper are well-known examples, but the energy costs of collecting them tend to be higher than for metals, so that glass and paper recycling on any significant scale requires the effort of many volunteer collectors, subsidy, coercion, or some combination of these.

The market cannot be relied upon to conserve energy resources. Although market forces have encouraged a remarkable improvement in the efficiency of electric power generation, thereby "saving" an enormous amount of fossil fuel that otherwise might have been burned to produce the same amount of electricity in less efficient plants, the market at the same time encourages the use of electricity in ways that are both thermodynamically and socially wasteful. Market forces have helped provide the average American with an automobile that makes him the envy of most of his world neighbors, yet they have also encouraged the design and use of that automobile in ways that make it the champion energy wastrel among modern machines. The market prices any resources, no matter how limited in fact, according to the cost of preparing it for use, as long as its availability exceeds the demand for it. Only when demand exceeds availability does the market price start shifting from the cost of production toward the true value of the commodity in society, and then it allocates the suddenly "scarce" resource, not according to social need for it, but according to the ability to pay for it, and it moves to the rich rather than the needy. Today, the direct pecuniary cost of energy is still a small portion of the total value of most goods and services. Primary aluminum and air transport are among the few exceptions. Consequently, the

self-interest of production managers and consumers cannot be expected to be a major factor in conserving energy supplies, and it is this selfinterest on which the market system is based. The alternative is governmental direction of energy conservation by means of mandated efficiency standards, incentives and disincentives applied through taxation and pricing systems, and end-use controls.

Recent projections by the Energy Research and Development Administration suggest that U.S. energy needs in the 1990s could be 20-40 percent below what was previously expected. A study by a private consulting firm of future energy needs in Nassau and Suffolk Counties on Long Island [18] indicates that no new powerplants will be really needed for a very long time and suggests that even the Shoreham nuclear plant, now under construction, was not necessary. There is, in other words, a very great potential for reducing U.S. energy demand.

The belief seems to be widespread that energy conservation means a lowered level of living, a sacrifice of a desired life style, and denial of economic opportunity to disadvantaged portions of society. Lee Schipper [19] and others argue persuasively that the strategies that would bring the largest savings in energy use would have few or none of these effects. Neither does there appear to be any demonstrable relation between gross energy consumption and employment. If the emphasis in conservation is kept on improving efficiency of use, social benefits should exceed the social costs.

SOCIAL COSTS OF ENERGY USE

The social benefits of energy use are linear and measurable; many of them accrue almost immediately and can be widely distributed within society. The social costs of energy use are nonlinear (low in the early stages of energy development, they later tend to increase faster than energy consumption) and difficult to measure; many of them are long delayed in their appearance and they tend to be concentrated both geographically and demographically.

An abundance of cheap energy, mainly from the fossil fuels, allowed the emergence of industrial and technological society, and accounts for the high material levels of living in the indusrtialized nations, as well as for the growing disparity in the conditions of life between the nations that consume a great deal of energy and the other 70 percent of the world's people. Great advances in medicine and public health are reflected in the increased life span and the conquest of contagion in the high-energy countries, as well as in the exploding populations that are bringing misery to the rest of the world.

In recent years some of the more localized social costs of energy use have become matters of general concern. Air and water pollution, strip mining, and the hazards of radioactive contamination have brought demands, implemented by legislation, for controls to be placed on energy exploitation. Now the economic and social hazards of energy scarcities are beginning to be perceived. All such social costs derive from increasing the use of energy beyond the limits of natural systems to supply the resources, absorb the wastes, and repair the damages. The environmental problems of the next 25 years are well foreseen. Most are already with us, and will change only in degree, not in kind. There will be strong pressure to expand greatly the mining

of coal and uranium by surface methods. There is no practical way to extract the thick, near-surface coal beds of the Rocky Mountains except by surface mining. There will be no other way to mine the really low-grade uranium and thorium deposits. It should be kept in mind, however, that even a ten-fold increase in the production from such mines will require the disturbance of a small fraction of the national surface, nothing like the fraction already covered by pavement. Probing of the continental shelf for oil and gas will continue. Oil spills and leaks are bound to occur, but the damage, like the drilling, will be ephemeral and, unlike mining, will leave no scars. The burning of fossil fuels in powerplants, blast furnaces, and automobiles will continue to pollute the neighboring air and land, but present control systems appear adequate to keep the risk to human health at acceptable levels-unless hitherto unsuspected pollutant hazards are discovered.

The nuclear fuel cycle carries the greatest potential for increased social costs over the next 25 years. The breeder-reactor powerplant, developed at great cost and representing not only a technology that other countries have accepted but a large replacement of the demand for fossil fuel, very likely will start to proliferate in the 1990's. Although its safety will still be questioned, proper siting, perhaps underground, probably can reduce the risk of the powerplant itself to a relatively insignificant level. The risks of a breeder economy will focus elsewhere. The chemical plants that will reprocess the spent nuclear fuel to recover unburned fuel and concentrate the highly radioactive fission products that must be treated as waste will conmany as 50 reactors. The concentrated wastes will be stored as liquids in tanks at the plant sites for as long as five years before being solidified and shipped to a federal waste repository. Such a plant will not contain energy in a form that would allow an accidental explosion, but it will be vulnerable to extreme geophysical events such as earthquakes or floods, and could become a target of sabotage or terrorist activity. So-called routine low-level radioactive discharges from such plants will be cause for concern, because some of the longer-lived isotopes can be biologically concentrated in the human food chain. The more chemical plants that discharge such "routine" wastes, the more chance there will be for environmental contamination and biological concentration. The ultimate waste repository, which has not yet been identified, will represent a hazard that will become important only as the quantity of stored waste builds up, and then-if the site has been properly selected-only of an extremely toxic material, plutonium. Not only is plutonium one of the most toxic substances known, but bombs can be made from it. The plutonium peril will be discussed later.

SUMMARY OF PROBLEMS AND POLICY ISSUES OF THE NEXT 25 YEARS

The energy problems of the next 25 years involve (a) controlling environmental pollution from the increasing use of coal and nuclear fuels; (b) replacing the lost supply represented by diminishing production of domestic crude oil and natural gas; (c) avoiding dependence on imports of energy; (d) analyzing the social costs and benefits of nuclear power and deciding on the best nuclear path to follow.

The principal policy issues related to these problems appear to be: (a) Should environmental controls on energy exploitation be relaxed in order to allow the use of domestic instead of foreign fuels, or of more abundant in place of scarcer fuels?

(b) Should emphasis be placed more on maintaining or increas ing energy supply rather than on conserving energy through improved technical and social efficiencies?

(c) If we assume that energy imports will continue to be needed. how can the nation move toward greater assurance of foreign supply at sufferable prices, at the same time developing some form of insurance against interdiction of this supply? Is it wise to offer the Soviet Union both capital and technologic knowhow in exchange for promises of oil and natural gas, when the new Soviet productive capacity will give that nation grater leverage in a world where energy control is so important?

(d) Should the development of new supplies of energy resources remain in the private sector, encouraged by government through cost-sharing, tax incentives, and price guarantees, or should government companies be organized to take over one or more of the functions of private enterprise related to energy supply?

(e) How forcefully should government encourage energy conservation? To the point of end-use controls and rationing? Short of that, to the level of a Btu tax on all nonrenewable energy forms and enforced efficiency standards in buildings and automotive vehicles? Or merely to the position of a truth-in-energy information campaign, leaving the market as the conservation agent?

(f) Should development of nuclear power be carried forward and, if so. should emphasis be on the fast breeder reactor, or on reactors of intermediate fuel-use efficiencies (but greater safety) such as the high-temperature gas-cooled reactor (HTGR) or the heavy-water reactor (CANDU)?

These are difficult questions to answer, not so much because of the conflicting interests involved, but because of a lack of critical information. We don't know what the world price of crude oil will be five years from now. We don't know how much oil and gas remains to be found and recovered from beneath U.S. soil. We don't know how effective energy-use restrictions or taxes will be. We can't be certain about public reaction to controls on the individual's freedom to use energy. We can't quantify the social and environmental hazards of nuclear power. But decisions will need to be made.

PROBLEMS OF THE COMING CENTURY AND RELATED POLICY ISSUES

WORLDWIDE SCARCITY OF OIL AND GAS

By the turn of the 21st century, a worldwide shortage of crude oil and natural gas is anticipated. The largest remaining reserves probably will be in the Soviet Union and the Persian Gulf region. The oil and gas resources of the United States and Canada will be, for practical purposes, exhausted, and oil and gas production from the North Sea probably will be declining. For its energy supply, the United States will be relying on coal, on nuclear-fission power, and on imports of oil and gas, and will be trying hard to replace these sources with