Volvo Cars’ Bi-Fuel technology for methane made its debut in 1995 in a Volvo 850, and the technology has undergone steady refinement during its ten years on the market. Since production of the latest generation of Bi-Fuel engines got under way in 2001, sales have met with considerable success and more than 12 000 cars (7 500 powered by methane and 4 500 by LPG) have been sold in Europe. Volvo has...