Renewable Transportation

There are several easily renewable technologies today that enable transportation today to run without the need to ever refuel using gasoline and some do not even require a battery to operate.

Solar Energy
http://en.wikipedia.org/wiki/Solar_car
A solar vehicle is an electric vehicle powered by a type of renewable energy, by solar energy obtained from solar panels on the surface (generally, the roof) of the vehicle. Photovoltaic (PV) cells convert the Sun's energy directly into electrical energy. Solar vehicles are not practical day-to-day transportation devices at present, but are primarily demonstration vehicles and engineering exercises, often sponsored by government agencies.

Wind Power
Here's one possibility:
http://www.wisegeek.com/contest/how-does-a-wind-powered-car-work.htm
The wind powered car that I have in mind is such that it converts wind power to electric energy which in turn moves the vehicle.
This concept is conceived from the fact that as you drive down your street and you put your hand out of the windows, you feel the enormous force of the wind, which in my view will do the world so much good especially in these troubling times of global warming.
In my minds eye, the vehicle will be such that there’s an intake valve seated on the roof to amass all the wind needed to power the car. An alternator connects to the to the intake valve which converts the kinetic energy to electrical energy. This electrical energy is connected to a DC battery pack which is the source of power to a controller. This controller converts the DC voltage to AC three phase voltage with the help of power diodes.
The accelerator is connected to the controller with cable through a pair of potentiometers which act as variable resistors to regulate the speed of the vehicle. The vehicle is very efficient because it has relatively few revolving parts and thus making it very fast. When the accelerator is floored, the full voltage is given out by the controller and when the pressure on the accelerator is taken off no power(zero power) is given off by the controller.
This vehicle uses a direct motor to wheel configuration which increases power. Multiple motors are connected to the wheels to increase both propulsion and braking system.
It also has a single gear system which is identical to the automatic gear system. This system utilizes the torque of the motor being a function of the current to improve upon the overall efficiency of the car.
The brake system relies on vacuum braking system which derives its braking force from atmospheric pressure on the lower side of the piston of the vacuum brake cylinder while a vacuum is maintained.
The aircondition can also be maintained and operated with a motor as well.
The wind taken in by the intake of the car is enough to cool the motors and prevent them from overheating and thus increasing efficiency of the vehicle.
Wind power continually charges the battery bank which is the main feature of this vehicle and there is no stipulated time for charging because as you drive, your battery bank is continually charged. There is a volt meter that tracks the flow of current to and from the battery bank.

Brake Regeneration
http://en.wikipedia.org/wiki/Energy_Regeneration_Brake
The Energy Regeneration Brake was the name for a system designed to automatically switch an electric motor into a generator as the vehicle slowed. Braking energy is captured so that batteries can be recharged, thus increasing the range of the automobile.
The system was first developed in 1967 by American Motors Corporation (AMC) in cooperation with Gulton Industries[1] for an experimental battery powered city car.[2] This concept car was called Amitron and its later iteration, the Electron. To achieve longer battery life between charges, the Amitron would have a "regenerative braking system" to generate battery-charging power as the car is slowed.[3]

Biofuel
http://en.wikipedia.org/wiki/Biofuel
Biofuel is defined as solid, liquid or gas fuel derived from recently dead biological material and is distinguished from fossil fuels, which are derived from long dead biological material. Theoretically, biofuels can be produced from any (biological) carbon source; although, the most common sources are photosynthetic plants. Various plants and plant-derived materials are used for biofuel manufacturing. Globally, biofuels are most commonly used to power vehicles, heating homes cornstoves and cooking stoves.

Magnetic Levitation
http://en.wikipedia.org/wiki/Maglev_train
MAGLEV, or magnetic levitation, is a system of transportation that suspends, guides and (usually) propels vehicles, predominantly trains, using magnetic forces. This method has the potential to be faster, quieter and smoother than wheeled mass transit systems, potentially reaching velocities comparable to turboprop and jet aircraft (900 km/h, 600 mph).