Document(s) 11 of 17

In preindustrial times, energy needs were limited to agrarian activities. Planting, harvesting, and transporting crops to small neighbouring urban centres did not require much energy. Transportation of merchandise and people was slow, and manufacturing (in foundries, potteries, and mills) was limited and consumed only small amounts of energy. Only minor quantities of energy were required to heat and light homes. These needs were satisfied by using animal, wind, and water power and by burning wood, charcoal, and other renewable fuels. Only negligible use of fossil fuels, such as coal, lignite, and peat, took place; and mining operations were limited to open-air quarries and pits.

Almost all preindustrial sources of energy were renewable. Forests could grow again naturally or be replanted, animals could be raised, wind and water were free. Under these circumstances, a steady rate of production and even some growth could be sustained for an unlimited period without exhausting the resource base. The effect on the environment of the use of these sources of energy was limited and, in most cases, only local. The impact of windmills and water mills was minimal, animal wastes contaminated only local areas and were biodegradable. The largest impact was probably a result of cutting trees for firewood:

Before the industrial revolution, energy needs were satisfied through various renewable sources of energy, such as wind power (windmill in La Mancha, Spain).

soil erosion and local decreases in biodiversity. At the global and regional levels, the effects were almost unnoticeable.

The industrial revolution

A dramatic change took place during the industrial revolution. Perhaps the most important element in the technological and social upheaval was the enormous increase in energy consumption. Industrial manufacturing required large amounts of energy to power the various types of engines that had been developed and spread throughout the rapidly expanding industrial world.

At the beginning of this period in Europe, energy needs were met by burning wood obtained from the many forests that covered the continent. Forests gradually disappeared from England, France, and Germany, and rapid deterioration of the environment took place. Soils were eroded, gullies formed on the more vulnerable slopes, and catastrophic floods and alluvial sedimentation became commonplace (see Chapter 4).

Another, more powerful source of energy used from the beginning of the industrial revolution was coal. Large-scale coal mining began in the 18th century and expanded during the 19th century. Coal-producing areas, such as Wales and England, the Ruhr basin in Germany, the Moselle valley in France, and several areas in other European countries, became the main foci of industrial development.

The environmental impact of coal use was intense. Coal mining destroys the soil, and burning coal produces emissions of aerosols, sulphur compounds, and other associated pollutants. The widespread use of coal produced smog over the cities and acid rain downwind of coal-burning factories. Although the industrial revolution allowed phenomenal productive growth, it transformed the main industrial areas into environmental nightmares.

The use of hydroelectricity

Hydroelectric power was one answer to the increasing need for energy and the problems caused by burning wood and coal. Electricity had been discovered by the end of the 19th century and the spread of its use during the first decades of the 20th century allowed a new approach to energy production. The first large hydroelectric dams were built in the 1920s and 1930s. The Hoover Dam — constructed between 1930 and 1936 on the border between Arizona and Nevada, with a capacity of almost 1.4 million kilowatts and a volume of 3.36 million cubic metres — represented the largest single investment in energy production in history. Just 6 years later, the United States constructed a new dam, almost four and a half times more powerful with a capacity of almost 6.2 million kilowatts, at Grand Coulee, and this was only the beginning! The dam-construction spree spread quickly throughout the world. Thousands of dams were built in most industrial and in many nonindustrial countries and, in many cases, their distribution decisively influenced the location of industries and related urbanization.

Hydroelectricity has been considered to be one of the less risky sources of energy. Hydropower is renewable, it does not contaminate the environment, and it does not produce unwanted emissions. At most generating sites, however, there has been considerable environmental degradation:

• River ecosystems have been profoundly disturbed.
• Many biological species have decreased in number or disappeared.
• Large tracts of good land have been flooded.
• Extensive wetland ecosystems have been destroyed.
• Supplies of nutrients to downstream alluvial plains have decreased, harming farmers who depended on these natural fertilizers.
• Newly irrigated areas have become the focus of waterborne diseases.
• Soils have been salinized or have become waterlogged.
• Fishing communities have lost their livelihood.
• Indigenous peoples have been displaced from their traditional lands, with insufficient compensation often improperly awarded.
• Archeological sites have been covered by water.
• Hydrological regimes have been modified.
• Seismic activity has increased in some places.

The environment and societies may pay a high price for this “clean” energy. In some cases, the price can be too high.

The age of petroleum

The beginning of the 20th century also witnessed the gradual replacement of solid fossil fuels (coal, peat, and lignite) with liquid fuels (petroleum) and, later, gaseous fuels (natural gas) (see box 7). Until the first oil well was drilled — in 1859 in western Pennsylvania, reaching a depth of 21 metres — petroleum was used only marginally. A few decades later, a hundred wells were active throughout the United States and elsewhere.

The growing availability and use of fluid fuels facilitated the development of more standardized means of transportation. In the early 20th century, the invention of the automobile represented a quantum leap in the use of these fuels, which gradually became the main source of energy in industrial countries. By 1950, daily oil consumption reached 11 million barrels, growing to 46 million in 1970. In the 1970s and 1980s, continuing increases in oil consumption were somewhat curtailed by limited availability and higher prices. In the 1990s, however, daily petroleum consumption is high and still increasing.

The pattern of discovery and development of oil fields reveals that continuing increases in petroleum extraction will not be possible for more than a few decades. Even in the most optimistic scenarios, if growing consumption is not curbed, acute scarcity will be felt between 2030 and 2040.

The effects of petroleum exploitation and use are considerable. First, groundwater injected into geological formations to replace extracted oil depletes usable aquifers, some freshwater reservoirs become brackish, and oil spills contaminate other surface and subsurface geological formations.

Second, emissions from burning oil are often responsible for smog, for increased concentration of pollutant gases and aerosols, and for the increase in CO₂ levels in the atmosphere. Lately, more efficient oil-burning technology is reducing the amounts of obnoxious emissions; however, there will always be artificial emissions that contribute to the stress on the atmosphere.

7.
Alcohol-powered cars in Brazil

In the 1970s, Brazil’s energy strategy was based on the use of alcohol from sugarcane to power automobiles instead of gasoline. The experience was only partially successful. About half of the country’s automobile fleet was converted to alcohol, but the early growth based on subsidies and support did not continue at the same rate when subsidies were discontinued. Currently, alcohol-fuel consumption is decreasing in Brazil, and nowhere else has alcohol been used for cars in a significant fashion.

The use of alcohol as fuel is not without problems. Although sugarcane is a renewable resource, its cultivation requires large areas of land, soil fertility is affected, erosion increases, and huge volumes of waste are produced. However, although the Brazilian government is abandoning open support for this alternative fuel, alcohol remains a major fuel for automobiles in Brazil.

 

Third, handling oil remains a hazardous enterprise. Currently, most petroleum is obtained offshore and transported by sea in large tankers. Accidents can produce environmental catastrophes in oceans, coastal areas, rivers, and lakes. Some oil spills from out-of-control wells may last for weeks and even months; in Kuwait, after the recent Gulf War, over 70 million tonnes of oil poured into the Persian Gulf. Tankers can break or sink, releasing huge volumes of crude oil. In the last 30 years, there have been more than 10 large oil spills in various coastal areas, several of which involved the release of more than 100 thousand tonnes of oil each into the sea: 300 thousand tonnes spilled as a result of the collision of the Atlantic Empress and the Aegean Captain off Trinidad and Tobago in 1979 (Funk & Wagnalls 1994); more than 200 thousand tonnes from the Amoco Cádiz on the coast of Brittany, France, in 1978; 250 thousand tonnes from the Castillo de Beliver in South Africa in 1983; and enough oil from the Exxon Valdez to contaminate 250 square kilometres of Alaskan coastal waters in 1989. As a result of these and other accidents and leakage, floating hydrocarbons have become a common feature of the world’s oceans, affecting the flora and fauna.

Nuclear power

Nuclear power as a source of energy was developed in the 1950s and 1960s. The first nuclear power plant was built in 1954; by the end of the decade, there were six; 20 years later, there were several hundred. Nuclear energy became a pillar in the energy strategies of many developed countries. However, it took two accidents (Three Mile Island and Chernobyl) to raise widespread awareness of the risks and initiate a reassessment of the use of nuclear power. There is growing opposition from communities and municipalities to the installation of new nuclear power plants in their proximity. Few reactors have been built in recent years and the future role of nuclear power is in doubt.

The clean options

The increase in energy consumption during the 20th century has been rapid. Between 1900 and 1989, energy use grew from 21 to 318 exajoules.¹⁰ Of this energy, about 88% comes from burning fossil fuels (Gibbons et al. 1989); the rest is obtained principally from nuclear and hydroelectric power. This distribution is the result of a general strategy based on fluid fuels, which was considerably shaken by the oil crisis of the early 1970s.

Today, well into the 1990s, the energy future of the planet is being looked at in a different light. Oil is becoming more difficult to find but, because it is easy to extract, transport, and use, it remains the main source of energy. Coal is easier to find, but “messy” to extract. In the long term, the main problem is that neither of these fuels is renewable and their volume is limited locally, regionally, and globally. In addition, their manipulation and use are environmentally “unfriendly” and risky.

Nuclear power is expensive and hazardous, as the problem of nuclear waste has not yet been solved. Hydropower has allowed growth of energy production in some areas, but has been identified as the cause of degradation of many river ecosystems, social dislocation of local communities, altered geological dynamics, and increased seismicity. The Brazilian alternative of alcohol from sugarcane is a renewable, easy-to-use energy source; however, its sustainability is doubtful.

A different approach altogether may be necessary. The world’s “hard-path” supply policies are leading to a dead end. According to Bott et al. (1983):

The desirable energy path is surely one of least risk (as distinct from least cost) for any given benefit . . .you will “never freeze in the dark” if you live in a super-insulated house and keep a few candles handy; you certainly run that risk if you live in a leaky house totally dependent on a distant nuclear power station.

¹⁰ One exajoule is 10¹⁸ joules and is equivalent to the heat generated by burning 170 million barrels of crude oil.

It appears now that a different, softer strategy is possible. This new strategy can and must be based in large measure on renewable and cleaner sources of energy. Inexpensive solar energy can satisfy the energy needs of large numbers of homes and small industrial plants throughout the planet. Although insufficiently used, its potential is widely recognized. Wind energy is being harnessed locally, but its utilization could be expanded. Currently, a few wind farms represent an interesting attempt to explore the feasibility of using this energy source on a larger scale. There have also been attempts to tap the energy of tides, waves, and geothermal sources. There are many other potential clean sources of energy that could be further explored and developed (for a discussion of sustainable energy strategies, see Goldenberg et al. 1988). If new strategies consider these alternatives, it will be possible to reduce considerably the need for environmentally unfriendly energy resources.

One of the easiest ways to deal with the energy problem is to develop policies aimed at reducing consumption. In most countries, energy consumption is too high and wasteful, houses are not insulated, heating water takes much more energy that it should, urban transportation by cars instead of public transportation is inefficient, large volumes of water are released unused from some hydroelectric dams while other unnecessary hydroelectric projects are being built nearby, and pricing policies often promote wasteful behaviour rather than conservation.

Appropriate changes in technology and associated policies could radically alter the current situation: cars are becoming more economical, houses are better insulated, the use of solar energy is slowly increasing in some areas of the world, and pricing policies are being based on more conservationist principles.

Finally, there is growing awareness that energy cannot be isolated from the general model of societies. Social organization and energy strategies are two aspects of a whole. Development models must be sustainable, both in the short term and in the long term, and deal concurrently with socioeconomic and energy issues. A sustainable model must include not only energy production, adequate pricing policies, and well-conceived energy-producing systems, but also appropriate urban planning, sustainable basin management, and a holistic socioeconomic vision in the formulation and implementation of policies. Potential sources of clean energy are plentiful; if imagination and political will are applied systematically, there will be no reason to fear the future.

Document(s) 11 of 17