Rushed Lifestyle

The only reason that we need fast cars is because we’re always in a hurry, and need to get to a job or somewhere fast. If we ever, one day, had no need for watches, and keeping time, and were never in a hurry, then there would be no need for fast cars except in ambulances. And anyway I enjoy the journey to places more than the actual destination, because you have to actually find things to do at the destination, and some times there’s nothing to do when you get there, so your better off enjoying the ride. But we would always still need to have fast ambulances. And if we somehow didn’t want to live rushed lives, we could, with today’s technology, have solar powered cars that go just as fast as horses did in the old days. But it would be free to drive, less maintenance, and not cost as much as a horse. And when they come out with 70% efficient multijunction solar panels eventually, then you will have vehicles just as powerful as today’s, that run off of solar power.
A car called "Eclectic" has already been made that is 100% solar powered.
But in the far distant future, in the best utopia possible, we would all have personal helicopters that wouldn’t break down and were easy to pilot. And we’d need infinite energy for them, so that they’d have enough power to take off with any weight and go any distance. This I believe will one day be possible with new energy technologies.
There might also be a market for a new invention of solar paneled motorized modules that pulled a chariot or a carriage behind them and the more power you needed the more horsepower worth of drive modules you would attach to your vehicle.