In this case the model just assumes wind is the last energy type to enter the mix and is not replaced by anything else down the line. Also, nothing is said about total energy consumption, only market share. Even optimists admit that Oil and gas will be rather scarce by 2040 and too precious to burn for energy.
The problem with nuclear fission is that (as Luis' chart shows) it seems to have peaked at 10% (possibly for political reasons), and oil at 50%.
Extrapolation is always unreliable but in this case. due to the logistic assumption, you can't have 150% of energy from wind. Can the last politician to go out the revolving door please turn the lights off?
