The Economic Competitiveness of Renewable Energy: Pathways to 100% Global Coverage

Chapter 3

The Importance of Energy Efficiency Measures

3.1 Traditional Extrapolation of Future Energy Demands or Alternatively “The Same or with Renewables Even Better Quality of Life with Much Less Energy”

There is a very simple calculation which is easy to remember and which demonstrates the false but often heard assumption that renewables are not able to power the future world energy demands. Using approximate numbers this goes as follows: Only one quarter of today’s global population – about 1.5 billion in OECD countries – is using three quarters of today’s primary energy – which is about 105 PWh. That also implies that today, three quarters of our global population only have one quarter of the primary energy left – clearly an unfair situation which has to change! As we would like to allow everyone in a future world to live in an environment with the same quality of life as we have, there is this simple calculation: At today’s quality of life, 70 PWh of primary energy is needed per one billion people. If we assume that the global population will have risen to 10 billion people at the end of this century, this would quite simply mean that we would have a primary energy need of 700 PWh! This 5 fold increase in 90 years is often described in terms of a small annual increase, in this case only 1.8% per year, which seems little but underestimates the real challenges in the long term. It is often argued that such a huge energy content of 700 PWh cannot be delivered by renewable sources. ...