America is exploring numerous alternatives to gasoline in the quest for a cheaper, more “American” energy source. One of the most promising alternatives is natural gas, which despite concerns about fracking is one of the most readily-available and affordable fuels out there. Could America ditch refined gasoline for its organic cousin?

Green Car Reports shares the story of vehicle consultant Carlab, which converted four vehicles, including a 2014 Ford Mustang GT, into bi-fuel cars capable of running both gas and CNG. Might Ford one day add this as an option?

It might happen sooner than you think, though it will take a little getting used to at first. That is where bi-fuel cars come in. Able to operate on both gasoline and compressed natural gas (CNG), bi-fuel vehicles allow you to use CNG when it is available, and gasoline when it isn’t. The engines are converted to use both fuels seamlessly, and the tanks have enough range for between 55 and 77 miles of driving, depending on the vehicle.

In addition to the Mustang, Carlabs also converted a BMW X3 crossover, a GMC Acadia SUV, and a Hyundai Sonata to show the versatility of these systems. Priced at $2 a gallon, these small CNG conversions could offer a gas-guzzling SUV a cheaper alternative to $4 a gallon gasoline for getting around town. Need to go farther? The vehicles switch seamlessly from CNG to gasoline, allowing you to continue your journey with peace of mind.

The bi-fuel system doesn’t even take up any cargo space, given the small 4.0 gallon-equivalent size of the tanks, though spare tires were removed. Projected cost of installing these systems at an annual rate of 20,000 units per year? Between $2,600 and $2,900 per car. For that extra few bucks, it wouldn’t take that long to make up the price premium in fuel savings, as long as you live near a CNG filling station, or install one in your home. So we wonder would you do it?