Bio-CNG is an Improvement on Gasoline and Diesel Compressed natural gas (CNG) is cleaner than gasoline, both in smog-forming emissions and in CO2, but CNG from bio-sources (as opposed to fossil fuels) is even cleaner and closer to carbon neutral, depending how it is made and compressed. That’s why Volkswagen has been

looking into bio-CNG for a while. Their latest showcase of this technology will take the form of a single-make racing cup where Scirocco running on bio-CNG will compete. … Read the full story on TreeHugger

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VW Showcases Bio-CNG with Scirocco Racing Cup, Claims 80% CO2 Reduction