Business guys look at line graphs and think that trends continue forever. The reality is, everything has a limit. No technology can improve indefinitely as technology is bounded by the limits of the physical world (see Moore's law). Only an industry scientist has the perspective to make an accurate prediction. Will solar technology improve to a point where it can beat the energy density of fossil fueles? Or is it physically impossible? Any qualified people willing to supply an opinion?

Personally my intuition says that we will go to solar, but at great cost. We will be forced to switch due to rising oil costs and even after the switch the energy supply will be so diminished that we will no longer be treating energy as frivolously as we do today.