On December 13, Audi celebrated its synthetic methane (e-gas) vehicle fuel plant, which is under construction in Werlte, Germany. Audi says that it is the world's first industrial plant for generating e-gas from CO2 and renewable electricity. Its end product will be hydrogen and synthetic Audi e-gas, which will be used as climate-friendly fuel for vehicles such as the new Audi A3 Sportback TCNG. E-gas production will begin in the spring of 2013.

The Audi e-gas plant will utilize renewable energy for electrolysis. The electrolysis process splits water molecules into oxygen and hydrogen, or Audi e-hydrogen, which at some point can be used to power fuel-cell vehicles. Since there's not much of a hydrogen fueling infrastructure in place yet, Audi can react the hydrogen with CO2 in a methane-processing unit to generate renewable synthetic methane, or Audi e-gas. The e-gas can be delivered to fueling stations through the local natural-gas network, since chemically speaking, the e-gas is nearly identical to fossil-based natural gas.

Audi unveiled the 2013 A3 Sportback in Munich, right before the 2012 Paris Motor Show in September. The five-door hatchback features a bi-fuel powertrain as part of the Audi e-gas project. Since compressed natural gas fueling stations are hard to find, the A3 also makes use of a 13-gallon gasoline tank to help give the car an effective range of around 745 miles.

The e-gas initiative is part of Audi's strategy of bringing cleaner, carbon-neutral fuel to internal combustion engines. The Werlte plant will generate enough CO2-neutral e-gas to power 1,500 new Audi A3 Sportback TCNG vehicles 15,000 kilometers (9,320 miles) each year. This compact five-door hatchback is scheduled to arrive at dealerships in late 2013.

Audi gets the CO2 to power the e-gas plant from a nearby biogas plant, operated by energy company EWE. The CO2 is made climate neutral by being chemically bonded into the fuel at the Audi e-gas plant, so that it won't pollute the atmosphere. Audi's new e-gas plant will be able to annually produce about 1,000 metric tons (1,102 US tons) of e-gas, and will chemically bind about 2,800 metric tons of CO2. That's roughly the equivalent to the amount of CO2 that can be absorbed by about 224,000 beech trees in a year.

Audi was given an award for its e-gas project in November. The Working Group for Efficient and Environmentally Friendly Energy Use honored Audi with an award and 15,000 euros.