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Iso-stoichiometric ternary blends - in which three-component blends of gasoline, ethanol and methanol are configured to the same stoichiometric air-fuel ratio as an equivalent binary ethanol-gasoline blend - can function as invisible "drop-in" fuels suitable for the existing E85/gasoline flex-fuel vehicle fleet. This has been demonstrated for the two principal means of detecting alcohol content in such vehicles, which are considered to be a virtual, or software-based, sensor, and a physical sensor in the fuel line. Furthermore when using such fuels the tailpipe CO₂ emissions are essentially identical to those found when the vehicle is operated on E85. Because of the fact that methanol can be made from a wider range of feed stocks than ethanol and at a cheaper price, these blends then provide opportunities to improve energy security, to reduce greenhouse gas emissions and to produce a fuel blend which could potentially be cheaper on a cost-per-unit-energy basis than gasoline or diesel.

The combination of high crude oil prices, energy security concerns and environmental drivers have resulted in an increased focus on alternative fuels. Gas to liquids (GTL) diesel is considered to be a promising alternative diesel fuel, given that it can be used directly as a diesel fuel or be blended with petroleum-derived diesel or biodiesel. GTL diesel fuels are predominantly paraffinic and possess several excellent inherent properties including virtually zero sulfur, very low aromatics (≺1%) and very high cetane values (typically ≻75). Currently GTL diesel is mostly sold into the European market as a blend stock for the extending and upgrading of petroleum-derived diesel fuels. Given GTL diesel's inherent paraffinic nature, the density of this product is below the European minimum 820 kg/m₃ EN590 specification (at 15°C).

There is a worldwide drive to reduce the dependence on fossil fuels, mainly driven by volatility in the crude oil price, political instability in oil-producing countries and environmental concerns. In several European countries, diesel passenger cars outsell gasoline-powered cars by a significant margin. Common rail diesel injection technology has played a significant role in making diesel engines more acceptable in light-duty applications, given the significantly improved emissions (due to better atomization) and engine noise offered by this technology. These developments have contributed to a renewed interest in alternative diesels like biodiesel and Gas to Liquid (GTL) diesel. Recently, CEN TS 15940:2012 was approved for publication. This specification will enable paraffinic diesel (including GTL diesel) to be sold commercially as a neat fuel or as a blend, containing up to 7% fatty acid methyl ester biodiesel (FAME).