I. Overview. Introduction. Commercial and noncommercial energy. Energy for subsistence and development. Human energy capacity. Supplemental energy needs. Energy balance. World energy outlook. Economic considerations. Environmental considerations. Solutions to difficult problems. II. Energy Use. Introduction. Agriculture's share of commercial energy. Commercial energy use for agricultural inputs. Commercial energy use and cereal output. Commercial energy for fertilizer production and use. Commercial energy for farm machinery manufacture and use. Energy from human labor. Energy from draft animals. Commercial energy for pump irrigation equipment manufacture and operation. Commercial energy for pesticide production and application. III. Energy Flow. Introduction. Energy surveys and analyses. Regional and national examples. Small-scale hydroelectric power plants. The need for systems approach. IV. Energy Management. Introduction. Germ plasm and its impact on energy use. Fertilizer and biological nitrogen fixation. Pest control. Irrigation. Mechanization of agricultural production. Energy management in the post-harvest system. Food processing. Energy and the food consumption system. Efficient energy management in agricultural is good business. V. Energy from Biomass. Introduction. Photosynthesis. Wood for fuel. Sources and availability of biomass feedstocks. Freshwater and saltwater plants. Classification of biomass fuels. Energy profiles. Biogas. Hydrogen. Ethanol. Methanol. Vegetable oil. Biomass feedstock. Solid fuels. Summary. VI. Solar Energy. Fundamentals of solar energy. Collection and storage. Agricultural applications. Future potential of solar energy. VII. Wind Energy. Introduction. Fundamentals of wind power. Wind energy conversion systems. Wind system applications. Wind characteristics. Feasibility studies. Economics. VIII. Hydropower.