One advantage to plug-in electric cars is that they can operate with no carbon footprint if the electricity used to recharge them is generated from renewable sources.

Burning liquid fuels, on the other hand, will always generate carbon emissions.

2014 Audi A3 e-tron plug-in hybrid presentation, Berlin

2014 Audi A3 e-tron plug-in hybrid presentation, Berlin

Now Audi is offering a way for German buyers of its new 2015 Audi A3 e-tron plug-in hybrid model to drive electrically with no carbon footprint at all.

A car running on grid electricity has no carbon tailpipe emissions, of course, but there's carbon associated with generating the electricity to recharge it.

Unless of course, that electricity comes from entirely renewable sources--solar, wind, or hydro.

And that's exactly what Audi's offering to German A3 e-tron buyers, through a deal with LichtBlick SE, one of Germany's largest independent energy providers.

MORE: Audi A3 e-tron: Full Details On Audi's Plug-In Hybrid

LichtBlick will provide electricity generated exclusively at hydroelectric power stations in Austria, Germany, and Switzerland to the A3 e-tron owner's home, for a basic monthly fee of 8.95 ($12.30) plus 29.76 euro cents ($0.41) per kilowatt-hour.

Geothermal Power Plant in Iceland

Geothermal Power Plant in Iceland

Audi says the greenness of the energy provided is certified, and notes that at least one-third of the electricity comes from relatively new hydro plants that are less than six years old. LichtBlick also plants 10 square feet of rainforest trees in Ecuador each month for each of its customers.

There is, incidentally, a carbon footprint associated with the parts and assembly of every car--even electric vehicles that operate with no emissions--but it's a small portion of the carbon associated with driving on liquid fuels, even at very high fuel efficiencies. But that's another story.

Meanwhile, Audi hasn't said anything about whether U.S. buyers of its A3 e-tron--which will be offered for sale in North America within the next 18 months--will be able to purchase carbon-neutral energy for recharging through the company.

MORE: 2015 Volkswagen e-Golf: Drive Report, First U.S. Sale Details

With Volkswagen hinting that it may offer such a capability for buyers of its upcoming 2015 Volkswagen e-Golf battery-electric car, the two VW Group brands might find some economies of scale in offering the same plan.

That all remains to be determined. Meanwhile, Audi e-tron drivers in Germany will now be able to drive with negligibly low carbon emissions even on a "wells-to-wheels basis."


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