Traditionally, if you wanted a car with a lower carbon footprint, you'd probably have to trade in your gas guzzler for an electric or hybrid vehicle. This is a barrier for even environmentally conscious car owners. But Germany-based startup Sunfire has created a new fuel that works in today's internal combustion engines. In April, the company unveiled its "e-diesel," made using electricity to create hydrogen from water and mixing it with CO2. The resulting fuel--nicknamed "Blue Crude"--is a diesel alternative that produces fewer pollutants. If necessary, the fuel can be combined with conventional diesel. In 2015, Audi partnered with Sunfire on a pilot plant in Germany that produces about 40 gallons of Blue Crude a day. They plan to build a bigger factory and sell the fuel for a very competitive 1 to 1.50 euros per liter.