Energy in life and society

Abstract

This chapter is concerned with the use and impact of energy on life and society. All activities of life and society are energy-based and energy-handling processes. The energy for all life on Earth comes from the Sun. Living organisms consume the available high-quality energy and return lower quality energy as specified by thermodynamics. Nonliving entities also consume energy over time, but life processes are more efficient in consuming energy. The three dominant stages of energy domestication in human societies are the survival stage, the stage of increased energy depletion, and the present stage of more efficient use of Earth’s energy resources (exhaustible and non-exhaustible). This chapter starts with a discussion of the three primary biochemical pathways, i.e., full series of energy-handling chemical reactions that take place in living organisms, namely, photosynthesis, respiration, and metabolism (catabolism, anabolism). Then, it examines the energy flow (food chains, food webs) in ecosystems including the efficiency of this flow. This chapter continues with a number of issues of the energy role in human society, namely the evolution of energy resources, the relation of energy with economy, the management of energy such that to achieve energy saving, the demand management which leads to “peak demand” minimization, and the use (consumption) of energy including relevant statistical data for the different parts of the Earth. The above issues and problems show the critical role of energy both for the life and the society, by providing the fuel needed for their existence, activity, and sustainability.