ABSTRACT

Energy is fundamental to economic systems and, indeed, to all life. Energy from the earth's interior drives their metabolic processes. Traditional agriculture is essentially a method of capturing solar energy for human use. Each stage of economic development has been accompanied by a characteristic energy transition from one major fuel source to another. The International Energy Agency estimates that governments spent about 500 billion dollar in 2015 to subsidize fossil fuels. The fossil-fuel age has brought significant economic progress to much of the world, but this particular route to development cannot be followed universally. This chapter discusses price, availability, and environmental impacts of energy in more detail. Energy statistics normally divide energy use among four sectors in an economy: transportation, industrial, residential and commercial (excluding electricity), and electricity. Projections of future global energy demand depend on assumptions regarding prices, technology, and economic growth. Developed (OECD) countries have historically been responsible for most of global energy demand, but this is changing.