The search for less-toxic alternative fuels is leading in many promising directions, one of which is bio-gas. Effectively a form of natural gas made from plants, the fuel was used this week to speed a modified B7 Audi A4 quattro to a new bio-gas world speed record of 226.6mph (364.6km/h).
Despite running on a mixture of methane and other gases generated by the controlled decomposition of grass clippings and sawdust, the Audi A4 used for the speed record generates a massive 700hp (522kW) from its overbored twin-turbocharged 3.0L V6 engine. What’s more impressive is that the powerplant is capable of producing upwards of 800hp (597kW), but output was limited this time ‘round to keep the transmission intact.
Source: Motor Authority