Synthetic fuel the fuel, and the fuel is less dense than conventional jet fuel allowing aircraft to fly further on the same load of fuel. The "cleanness" of these FT synthetic fuels is further demonstrated by the fact that they are sufficiently non-toxic and environmentally benign as to be considered biodegradable. This owes primarily to the near-absence of sulfur and extremely low level of aromatics present in the fuel. One concern commonly raised about the development of synthetic fuels plants is sustainability. Fundamentally, transitioning from oil to coal or natural gas for transportation fuels production is a transition from one inherently depletable
Ethanol fuel by country The first flex motorcycle was launched to the market by Honda in March 2009, and a second model in September 2009. By the end of 2009, both Honda flexible-fuel motorcycles had sold a total of 183,375 units, representing an 11.4% market share of the Brazilian new motorcycle sales in that year. Two other flex-fuel motorcycles manufactured by Honda were launched in October 2010 and January 2011. During 2011 a total of 956,117 flex-fuel motorcycles were produced, raising its market share to 56.7%. Cumulative production of the four available flex fuel models since 2009 reached 1.48 million units in December 2011.