Unit 2 Energy in Transition
The era of cheap and convenient sources of energy is coming to an end. A transition to more expensive but less polluting sources must now be managed.
John P. Holdren Understanding this transition requires a look at the two-sided connection between energy and human well-being. Energy contributes positively to well-being by providing such consumer services as heating and lighting as well as serving as a necessary input to economic production.But the costs of energy － including not only the money and other resources devoted to obtaining and exploiting it but also environmental and sociopolitical impacts － detract from well-being.
For most of human history, the dominant concerns about energy have centered on the benefit side of the energy － well-being equation. Inadequacy of energy resources or (more often) of the technologies and organizations for harvesting, converting, and distributing those resources has meant insufficient energy benefits and hence inconvenience, deprivation and constraints on growth. The 1970’s, then, represented a turning point. After decades of consta
ncy or decline in monetary costs － and of relegation of environmental and sociopolitical costs to secondary status － energy was seen to be getting costlier in all respects. It began to be plausible that excessive energy costs could pose threats on a par with those of insufficient supply. It also became possible to think that expanding some forms of energy supply could create costs exceeding the benefits.
The crucial question at the beginning of the 1990’s is whether the trend that began in the 1970’s will prove to be temporary or permanent. Is the era of cheap energy really over, or will a combination of new resources, new technology and changing geopolitics bring it back? One key determinant of the answer is the staggering scale of energy demand brought forth by 100 years of unprecedented population growth, coupled with an equally remarkable growth in per capita demand of industrial energy forms. It entailed the use of dirty coal as well as clean; undersea oil as well as terrestrial; deep gas as well as shallow; mediocre hydroelectric sites as well as good ones; and deforestation as well as sustainable fuelwood harvesting.
Except for the huge pool of oil underlying the Middle East, the cheapest oil and gas are already gone. Even if a few more giant oil fields are discovered, they will make little difference against consumption on today’s scale. Oil and gas will have to come increasingly, for most countries, from deeper in the earth and from imports whose reliability and affordability cannot be guaranteed.
There are a variety of other energy resources that are more abundant than oil and gas. Coal, solar energy, and fission and fusion fuels are the most important ones. But they all require elaborate and expensive transformation into electricity or liquid fuels in order to meet society’s needs. None has very good prospects for delivering large quantities of electricity at costs comparable to those of the cheap coal-fired and hydropower plants of the 1960’s. It appears, then, that expensive energy is a permanent condition, even without allowing for its environmental costs.
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The capacity of the environment to absorb the effluents and other impacts of energy technologies is itself a finite resource. The finitude is manifested in two basic types of envir
onmental costs. External costs are those imposed by environmental disruptions on society but not reflected in the monetary accounts of the buyers and sellers of the energy. “Internalized costs” are increases in monetary costs imposed by measures, such as pollution-control devices, aimed at reducing the external costs.
Both types of environmental costs have been rising for several reasons. First, the declining quality of fuel deposits and energy-conversion sites to which society must now turn means more material must be moved or processed, bigger facilities must be constructed and longer distances must be traversed. Second, the growing magnitude of effluents from energy systems has led to saturation of the environment’s capacity to absorb such effluents without disruption. Third, the monetary costs of controlling pollution tend to increase with the percentage of pollutants removed.
Despite these expenditures, the remaining uninternalized environmental costs have been substantial and in many cases are growing. Those of greatest concern are the risk of death or disease as a result of emissions or accidents at energy facilities and the impact of energy supplied on the global ecosystem and on international relations.
The impacts of energy technologies on public health and safety are difficult to pin down with much confidence. In the case of air pollution from fossil fuels, in which the dominant threat to public health is thought to be particulates formed from sulfur dioxide emissions, a consensus on the number of deaths caused by exposure has proved impossible. Widely differing estimates result from different assumptions about fuel compositions, air pollution control technology, power-plant sitting in relation to population distribution, meteorological conditions affecting sulfate formation, and, above all, the relation between sulfate concentrations and disease.
Large uncertainties also apply to the health and safety impacts of nuclear fission. In this case, differing estimates result in part from differences among sites and reactor types, in part from uncertainties about emissions from fuel-cycle steps that are not yet fully operational (especially fuel reprocessing and management of uranium-mill tailings) and in part from different assumptions about the effects of exposure to low-dose radiation. The biggest uncertainties, however, relate to the probabilities and consequences of large accidents at reactors, at reprocessing plants and in the transport of wastes.

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