ABSTRACT
Global oil production will peak in the coming decades, followed by natural gas and coal. These turning points constitute an unprecedented watershed in human history. This chapter focuses on some of the critical challenges we face in the transition from conventional fossil fuels to alternative sources, particularly solar energy. Foremost is the capacity for renewable fuels to develop into the functional equivalent of fossil fuels, i.e. to have a similar capacity to generate goods and services per unit of energy input. The cost of many renewable energy systems has declined in the past two decades, but significant challenges remain. This chapter describes the nature of some of those challenges, especially with regard to the prospects for overcoming the spatially diffuse nature of many renewable energy systems. It also explores the relationship between energy use and economic growth, and the factors that determine the strength of that relationship.
