There is several orders of magnitude more solar energy falling on the earth's surface each day than we use as a species so far. Energy availability is not the issue. Capture and conversion to useful forms is the issue. Furthermore, while I know that some people here diss the space program, serious studies have been done about increasing the captured solar energy from earth orbiting power stations and beaming that energy back to the ground as low intensity microwaves. None of thid involves creating energy, just capturing it. So go figure - we already have more energy hitting the earth's surface than we use from fossil fuels. And we already have the know-how to even expand upon that to capture more solar energy in the near earth region.

So what's the problem? The problem we have is not in capturing available renewable energy. The problem we have is one of mindset, of psychology, and of deliberately choosing to begin going down a road towards a renewable sustainable lifestyle. This problem is not only about energy. It's also about the myth of endless growth (which must stop) and that includes the endless growth of human population.

Even at 6 billion people, we have the knowledge to make the world a sustainable place. It would be very very different from the culture in which we live today but it doesn't have to be medieval serfdom or mad max. We just have to choose to do it. The sad thing is that so far we have actively refused to deal with these issues, especially the myth of endless growth being sustainable.

We will NOT be able to fuel the cars of the people that will feed the people also using their car in order to build those space solar panel.

Maybe you havent understand that Oil is the energy subside of everything NASA scientist could come up with.

I'm certainly aware of our planet receiving more solar energy than what is used as fossil fuels.  The problem reside in getting it concentrated enough.  

Even if we could (for very not any good reason) power some kind of car, the problem would then reside in getting enough nat gas or coal to keep on manufacturing fertilizers.

The problem is NOT a supply problem, it's a DEMAND problem.  Until the system is working, you will be able to use your car.  Once the system break, you wont need your car.

Actually, the demand problem will be solved rather easily (at least in the USA). Most people won't be buying gasoline because they won't be able to afford it. A trip in the car will be an important journey done for a purpose, because it will be too expensive to waste on anything trivial. There is a giant gap opening in the USA between the haves (top 10%) and everybody else. Rising oil prices are going to put the nail in the coffin.
Using satellites to convert solar energy to microwaves has an extremely low EROEI. Its not that the technology is impossible, its just impractical. Remember 1/R^2 losses.