STUTTGART, Germany- Fiat’s 900cc TwinAir Turbo methane-powered engine has been named ‘Best Green Engine of the Year” at a 2013 Engine Expo in Stuttgart, Germany.Launched in 2012 on the new Fiat Panda, the compressed natural gas (CNG) two-cylinder engine combines the environmental benefits of methane with turbo power to produce 59kW at 5500rpm and 140Nm at 2500rpm. Powering the 2012 Panda TwinAir Turbo, the engine produces 86g/km of CO2 and uses 3.1kg of methane/100km.NATURAL POWERCompared to the petrol version, the TwinAir bi-fuel includes specific fuel system components, including the intake manifold, injectors, electronic engine control system and valve seats with specific geometry made of low-wear material.Currently the new 900cc TwinAir Turbo Natural Power 59kW is available in some markets on the Fiat Panda and 500L Natural Power models.WHICH IS BETTER - CNG or LPG?Propane provides 2.5 times more energy per unit of volume than natural gas but, in some markets, natural gas (methane) costs one-sixth the price of LPG. You do the math...CNG must be kept at much higher pressure than liquefied petroleum gas (LPG), so fuel tanks are often larger and heavier, which can negatively affect vehicle range. CNG used as fuel, depending on the country, can costs less and could be a better choice for buses and taxis.To turn natural gas into a liquid (LNG) it must be cooled to -162°C. At such a low temperature, it takes up less space than CNG, so larger amounts can be put into tanks and transported.ECOBOOST WINS AGAINEarlier in June 2013, Wheels24 reported that Ford's one-litre EcoBoost petrol engine had been chosen as 2013 International Engine of the Year, the second year in a row the three-cylinder has earned the award.It's used in South Africa in the Fiesta and EcoSport and received the highest score yet in for any engine winning the “Best Engine Under 1.0” category at the annual awards in Germany.