Understanding the volatility of ethanol/gasoline blends

The EU’s Renewable Energy Directive (RED, 2009/28/EC) mandates that 10% of transport fuels on an energy basis must be derived from sustainably produced, renewable sources by 2020. As also required by the RED, each Member State must evaluate how they intend to reach their individual mandate based on their unique combination of energy resources and transport demands.

The results of these evaluations have been published in each country’s National Renewable Energy Action Plan (NREAP). In general, the NREAPs anticipate that conventional bio-components, such as ethanol from sugar fermentation and fatty acid methyl esters (FAME) esterified from natural oils, will largely be used to meet the 2020 mandates because of the slower pace of development of more advanced bio-components.

Although today’s EU-wide specifications allow up to 5% v/v ethanol in gasoline (E5) and up to 7% v/v FAME in diesel fuel (B7), work is progressing in the European Committee for Standardization (CEN) to increase these blending limits.