Coal and Oil: Energy Sources and Industrial Impact

Coal: Formation and Industrial History

Coal is a black, stratified sedimentary rock formed from the decomposition of plant remains. Its quality and calorific value depend on the duration of the formation process, ranging from hard coal (primary era) to brown coal.

During the First Industrial Revolution, coal production played a hegemonic role due to increased protectionism against cheaper foreign alternatives. The isolation following the Spanish Civil War and the subsequent period of autarky hampered the incorporation of new technologies. Eventually, the massive substitution of coal with oil led to a decline in consumption and the closure of many mines. The 1975 energy crisis briefly pushed consumption back up, but since 1984, production has declined due to:

• Resource Depletion: Some rich deposits have been exhausted, while others are of poor quality, limiting their utility.
• Operational Challenges: One-third of the mines are underground, making it difficult to utilize large-scale extraction machinery.
• Processing Costs: The coal extracted requires cleaning and washing, which significantly increases production costs.

Production is concentrated in thirteen major watersheds, including the Asturian, Leon, and Palencia areas, though this does not achieve national self-sufficiency. The primary use of coal is for electricity generation in power stations, often coupled with hydropower plants.

Environmental Impact of Coal Plants

Power plants are geographically dispersed, influenced by the proximity to coal deposits and water sources for cooling. A significant disadvantage is the use of high-sulfur coal, which contributes to acid rain.

Oil: Composition and Economic Role

Oil is a dark mineral oil composed of a mixture of hydrocarbons. It is formed by the decomposition of marine organisms, plants, and animals over millions of years, accumulated in sedimentary layers.

Oil ranks first in energy consumption, experiencing a boom during the 1960s industrial development due to its low cost. While the 1975 price hike did not immediately reduce consumption, the 1979 crisis prompted efforts to lower dependency. Between 1985 and 1995, oil costs trended downward following price liberalization. Since then, prices have fluctuated based on OPEC production levels.

Domestic Production and Industrial Utility

Domestic oil production remains scarce, located primarily along the Mediterranean coast and select inland enclaves. Petroleum derivatives are essential for various sectors, particularly:

• Transportation: Diesel and gasoline.
• Petrochemical Industry: Gasoline and kerosene for fertilizers, plastics, and electricity generation.