Most car companies seem to be focussing on plug-in vehicles off late, however, a new report from Pike Research reveals that consumers might be seeing a lot more natural gas vehicles in the market.

Though only a handful of automakers currently offer natural gas vehicles in the U.S. (with Honda being the notable exception), Pike Research predicts that the market will expand to 19.9 million NGVs by 2016 worldwide — with most of the growth occurring in places like India, Pakistan and Iran. According to the study, global sales will rise from the 1.9 million vehicles per year to more than 3.2 million units by 2016.

India’s sales itself will hit 612,389 units by 2016. On a much smaller scale, the study also claims that sales in the U.S. market will increase by 25.4 percent annually, and will sell 32,619 CNG-fueled vehicles by 2016 (the highest growth rate of any country).

Unfortunately, fueling infrastructure may not be sufficient the study reports. Pike Research predicts that there will only be 26,000 natural gas refueling stations worldwide by 2016, up from the 18,000 stations in use today. As of 2008 the U.S. only had about 1,500 natural gas fueling stations.

As we’ve argued before CNG (compressed natural gas) is less expensive than gasoline and burns cleaner, resulting in 30 to 40 percent less greenhouse gas emissions, according to the U.S. Environmental Protection Agency. It is also helps us wean off our dependence on foreign oil since 90 percent of it is produced in the U.S. If we can get enough infrastructure set up in time, it may be a great alternative to petroleum cars.

“Corporate and government fleets are the strongest adopters of natural gas vehicles,” says senior analyst Dave Hurst. “Not only will this trend continue, but in fact fleet sales will increase as a percentage of all NGV sales, representing two-thirds of the total market by 2013. More and more fleet managers are attracted to the lower fuel costs of natural gas, in addition to the opportunity to reduce their vehicles’ carbon footprint.”

In that vein, a taxicab company in Chicago announced last week that it will be using natural gas-powered Ford Transit Connect vans as part of its fleet.

The company, Taxi Medallion Management, which is affiliated with Yellow Cab Chicago, said it bought the vans as an effort to cut its total emissions by 25 percent.

Several other cab companies are also looking into the option, so Pike may be right about its numbers.