Continuing with our clean energy theme this week, we’d like to introduce you to E-Gas.
It begins with green electricity, water, and carbon dioxide. The end products are hydrogen and a synthetic methane Audi calls “e-gas.” It is virtually identical to fossil natural gas and is climate neutral. Audi opened an e-gas plant in Germany this month, making it the first automobile manufacturer to develop its own sustainable energy chain.
Audi anticipates that the E-gas from the new plant will power 1,500 new Audi A3 Sportback G-Tron vehicles for 15,000 kilometers (approximately 9,320 miles) of CO₂-neutral driving every year. The lightweight aluminum 110-horsepower/1.4-liter turbocharged engine in the five-door model can burn natural gas, biomethane, and Audi E-gas; with its bivalent design it can also use gasoline. This gives it a total range of some 1,300 kilometers (807 miles) from each refueling.
The Audi A3 Sportback G-Tron, which is scheduled for launch in Germany later this year, consumes on average less than 3.5 kilograms (7.72 pounds) e-gas per 100 kilometers (62.14 miles). Greenies will appreciate that its CO₂ tailpipe emissions are less than 95 grams per km (152.89 g/mile). Even in a comprehensive wheel-to-well analysis that includes the construction and operation of the e-gas plant and the wind turbines used to power it, CO₂ emissions are just 20 grams per kilometer (32.19 g/mile).
“But how is E-gas made and distributed?” We’re glad you asked. The E-gas plant works in two process steps: electrolysis and methanation. In the first step, the plant uses surplus green electricity to break water down into oxygen and hydrogen. One day, the hydrogen byproduct could power fuel-cell vehicles. For the time being, however, in the absence of an area-wide infrastructure, a second process step is carried out directly: methanation. The hydrogen is reacted with CO₂ to produce synthetic methane, or Audi e-gas. It is virtually identical to fossil natural gas and will be distributed via an existing infrastructure, the German natural gas network, to local CNG filling stations. The plant is scheduled to begin feeding Audi E-gas to the grid in Fall 2013.
Customers can order a quota of E-gas when they purchase the car. This enables them to take part in an accounting process that ensures the amount of gas they put in their vehicle at the natural gas filling station is supplied to the grid by the Audi E-gas plant. Payment and billing is handled via the Audi e-gas refueling card.
So what does this mean for you? While the vehicle and its sustainable fuel source haven’t made it to the United States yet, Audi has demonstrated an alternative fuel creation and distribution chain that can be implemented in other areas and used in other natural-gas-powered vehicles as well. Let’s watch to see how this progresses stateside!