In a previous article, we discussed how alternative-fuel cars came to be developed and why they are now becoming popular. The next question is: what exactly are the choices available to consumers who are interested in this type of vehicle?

Following are some of the better-known versions of cars that use non-traditional fuel:

* Compressed air cars are emission-free piston engines that use compressed air as a source of energy. They achieve this when cold expanded air from a pressurized carbon-fiber tank is warmed with environmental heat at normal temperature. This air is then delivered to the engine as its energy source.

* Battery electric vehicles use batteries like lead acid, absorbed glass mat, nickel metal hydride, lithium ion, lithium poly and zinc-air as their energy source. These batteries are rechargeable, but they are expensive.

* Solar cars are electric vehicles that run through solar energy. These vehicles have solar panels that trap the energy from the sun and convert it to electric energy. Though it is good that the energy it uses is just free, it is not very practical to use as a form of transportation. Now, it is commonly used in car race competitions in Australia, United States and Canada.

* The ammonia-fueled car has a diesel engine that has been modified for ammonia use. During combustion, it has no emissions but it can be more dangerous compared to petrol or LPG.

* Biofuel cars use one of these three: bio-alcohol called ethanol, biodiesel, or biogas. The use of ethanol as an engine fuel is a renewable resource since it can come from sugar-rich crops. It is very promising due to its environmental and economical advantages.

Biodiesel on the other hand, has lower density than its fossil diesel counterpart. The only advantage for biodiesel is that it produces lower emissions than diesel and gasoline engines. Finally, biogas is the one utilized when unrefined gas has been purified. In the process, water, particles and hydrogen sulfide is removed.

* Hydrogen cars use hydrogen either through combustion or fuel-cell conversion to make motor engines work. The only byproduct of both processes is water and heat so it is not harmful to the environment.

* Liquid nitrogen cars are cars that readily refill nitrogen gas when it runs out. This is attained by storing energy and by using this energy to liquefy air. As air is liquefied, liquid nitrogen is produced through evaporation and is distributed throughout the engine. When heat is exposed to liquid nitrogen, it results into an energy source that can power up the engine.

* A liquefied petroleum gas (LPG) car uses propane and butane as its power source. It undergoes the traditional combustion process just like gasoline, but yields lesser amounts of carbon dioxide.

* Steam engine cars are those that burn wood, coal or ethanol in a broiler. The heat produced converts the water into steam, which in turn creates pressure. This pressure now allows the engine to move. These cars take quite a long time to start up, but once on track, it can reach up to a hundred miles per hour. They’re good for transportation, but are extremely costly.

* Hybrid cars are also known as petrol-electric hybrids or gasoline-electric hybrids. These use a lot of systems to make a car work. Initially they have a petrol engine, and then they also have an electric motor that jolts in at various stages to save petroleum. Currently, Toyota Prius is the first and largest manufactured commercial hybrid car in Japan since its creation in 1997. This was followed by Honda in 1999, when they released their Honda Insight.

Source by Rod Barcelon