Are renewable energy resources large enough to replace non-renewable energy?

Abstract

While the very large potential of renewable energy has been known to some scholars at least since the end of the 19th century, the potential is still today commonly underrated in public debate. To get the physical proportions right is a necessary first step in a sensible discussion on possible and desirable development paths. The primary purpose of this chapter is to answer the question if the resources of renewable energy flows are large enough to completely replace fossil fuels and nuclear energy, and to indefinitely support a world population of 9-10 billion people at a living standard equivalent to present day industrialised societies. A second purpose is to outline what expectations we may have on each of the different renewable flow resources. The potential of the conversion route via bioenergy is excluded from this discussion but is treated more extensively in in another book in this e-book series.1 Our scope is limited to potentials of electricity production, but since electricity is an energy form of high quality (see Chapter 2) its use is versatile. It is not unlikely that many applications that today are powered by the chemical energy in fuels will switch to electricity in the coming decades2. Electricity can also, at a cost, be converted to chemical energy stored in hydrogen or even hydrocarbons (see Chapter 12). Hence, a comparison makes sense not only to the global electricity demand, but also to the total energy demand.