Natural Gas (CNG) vehicles are a great way to decrease your carbon footprint. Natural gas cars run off of natural gas that is used in our homes. There are a variety of models out there that are available for natural gas vehicles. Natural gas vehicles are more efficient than petroluem based cars. Natural gas is also produced locally in the United States which decreases the transport costs and emissions.
Natural gas is also a lot cheaper than petroleum based gasoline. With the efficiency and price of natural gas, a gallon of gas equivalent costs about 1 dollar a gallon.
Here is one natural gas vehicle that you can purchase now.
Honda Civic Natural Gas Vehicle (NGV): The Civic GX NGV looks like a conventional Civic but is powered by compressed natural gas. It's a very efficient vehicle and boasts near zero emissions. You can fill the tank at one of the many natural gas locations, or install a conversion kit to your home so you can fill up from your natural gas provider. The Civic starts at a base price of $25,090. See http://automobiles.honda.com/civic-gx/ for more information.
There are other cars that offer CNG solutions such as the Ford Crown Royal CNG, but not in new models. You can find natural gas cars for sale on sites such as Craigslist.com or specific natural gas car retailers. The Civic NGV is the best choice for a natural gas car. There are also conversion options for your current car to become a natural gas vehicle. However, these often times require certification from the state in which you live and can become costly.
reference link:
http://automobiles.honda.com/civic-gx/