Modern concepts on Running vehicles on alternative fuels

Alternative fuel vehicles are basically those that run on fuels other than petroleum and are are aimed at increasing the mileage and also to conserve the natural reservoir of the precious fuel in the long run. Some of the common fuels available at present include.

Alcohols - ethanol and methanol.

Compressed natural gas (CNG) - natural gas under high pressure.

Electricity - stored in batteries.

Hydrogen - a very special type of gas.

Liquefied natural gas (LNG) - natural gas that is very, very cold.

Liquefied petroleum gas (LPG) (also called propane) - hydrocarbon gases under low pressure.

Liquids made from coal - gasoline and diesel fuel that doesn't come from petroleum.

Biodiesel - a lot like diesel fuel, but made from plant, oil or animal fat.

The basic concern for using these alternative fuels stems also from the fact that the pollution from the traditional fuels has been very high and hence these alternative fuels are also deemed to be more environmental friendly. Also increasing the alternative fuel usage gives a broad variety of choices to the consumers thus broadening the supply base and reducing the environmental impacts.

The futuristic Fuel (Hydrogen):

Since Hydrogen burns nearly pollution free it has been touted as very good alternative. It is also very abundantly available in the environment. As of now only a few experimental vehicles are used so as to test the potential of hydrogen. Hydrogen is the lightest element on the earth as seen on the periodic table. A simple electrolysis procedure releases hydrogen from water components (H2O). But nowadays most of the hydrogen is produced from natural gas. In an internal combustion engine, the burning of hydrogen produces a small amount of other gases which are mostly oxides of Nitrogen because the combustion takes place place in an environment of air.

Though hydrogen could be compressed and stored in cylinders, it contains less energy per volume as compared to traditional fuels like gasoline or ethanol. Liquid Hydrogen by way of cooling of hydrogen could also be used as a fuel but is much more costly. Hydrogen has also been used in fuel cells which could be utilized for many other purposes. Hydrogen Vehicles have almost zero Green house gas emissions thus making it environmental friendly.

Hybrid Vehicles:

Hybrid means something that is mixed together with 2 things. Avery new innovative vehicle that has hit our roads are the hybrid vehicles. Two cars worth a mention is the Toyota Plus and Honda Insight. The Honda Insight can go up to 68 miles per gallon on a freeway. The primary power comes from the gasoline engine, but uses the electric motor to climb hills and while accelerating and climbing hills. The electric motor batteries are charged by regenerative breaking i.e energy from forward momentum is captured during breaking. Ford Escape is another hybrid utility vehicle that has been under production since 2003. It gives 40 miles per gallon. To own these these vehicles is a little expensive in the beginning, but incentives if given by the government can very well promote the cause of development of these vehicles.

Fuel Cell Vehicle (Zero Emission Vehicles):

Fuel cells though it looks like a new concept is not so. It has been used in spacecrafts for many years to power the electric equipment. These electric equipments are fueled with hydrogen from the rockets fuel tanks. Fuel cell vehicles turn hydrogen fuel and oxygen into electricity. This generated energy powers an electric motor of the vehicle. Fuel cells combine oxygen from the air with hydrogen from the vehicles fuel tank to produce electricity. When oxygen and hydrogen are combined they give off energy and water(H2O). There is no combustion or burning in this case.
A simple animation below would help to understand the working of the cell.

There are number of ways by which hydrogen could be supplied to the fuel cell. One way is to put hydrogen gas into the fuel cell along with air. Hydrogen gas can come from gaseous or liquid hydrogen stored on the vehicle. In order to carry gaseous hydrogen on a vehicle it must be compressed up to a pressure of about 3000 pounds per square inch and needs to be stored in high pressure containers.

The hydrogen could also be stored in liquid form in the vehicle, which is very cold indeed i.e 423.2 degree Fahrenheit below zero. The containers are able to hold pressure and are also insulated to keep the hydrogen from warming up. Warming the liquid or lowering the pressure can releases gas which can go to the fuel cell.

A 'reformer' is a type of device that removes hydrogen from hydrocarbon fuels like methanol or gasoline. But it changes from a zero emission vehicle to a low emission vehicle because a fuel other than hydrogen has been used.

A "Direct Methanol fuel cell" can be fueled from methanol directly. This does not require a reformer. The fuel cell removes the hydrogen from the methanol. Many people into manufacturing cars believe that fuel cell vehicles may be the technology of the future. As of now only prototype vehicles have been developed and research is underway to build more cost efficient vehicles.