Introduction: The Essential Resource

Energy in the form of heat and work has always been crucial for human beings. Wood usage as a source of heat goes as far back as the control of fire. Wind and water have been used for millennia, but the most important source of mechanical energy until a few centuries ago was the labour of domestic animals and human beings (peasants and slaves). This all changed with the discovery of fossil fuels as a source of high-density chemically stored energy.

Coal was already known as a fuel in early dynastic China and ancient Rome. It was used for heating in medieval Europe but was considered inferior to wood because of its foul smoke. Moreover, it was harder to obtain in most places. Under the pressure of wood shortage in 17th-century England, coal became a more common fuel. Chimneys protected people from the immediate effects of smoke. By 1700, the fraction of coal in energy use in the United Kingdom exceeded already 50 percent (Figure 7.1). With the invention of the steam engine, its use got another boost. Like the use of coal, the principle of the steam engine had been discovered long before, in both the Chinese and Roman empires. At those early stages, no practical uses were found for it. In 18th-century England, however, circumstances were highly propitious. Initially, the steam engine was developed as a device for pumping water from the coal mine shafts, which made the coal more easily accessible. In turn, the cheaper coal was used to power other steam engines, some of them propelling the ships and locomotives that transported coal to the growing number of users. This further lowered the cost and expanded the market. In 1850, coal supplied over 90 percent of energy use in the United Kingdom. It was one of those positive reinforcing feedback processes that ignited the industrial revolution. But more was to come.