M85 is a fuel consisting of 85% methanol and 15% gasoline (petrol).^[1] It is a potential alternative to traditional gasoline and ethanol. M85 is similar to E85, but cannot be used in vehicles designed for E85. Although it is similar in composition, M85 is not as well known as its ethanol counterpart. Despite these issues, methanol is considered a viable alternative fuel as it contains high levels of hydrogen.^[2]

Background

Methanol, the primary component of M85 fuel, is primarily derived from natural gas, offering a liquid alternative for transporting gas to distant markets. Efforts are being made to convert "waste" natural gas into methanol, providing an efficient means of utilizing excess resources. While some methanol is produced by fermenting biomass, it is not yet economically competitive. Notably, M85 has the potential to be a preferred means of storing hydrogen for fuel-cell electric vehicles in the future.

Efforts to introduce M85 into fuel markets, particularly in California, have been made. However, there is no nationwide transportation network for bulk M85 fuel. The industry's recent focus on methyl tert-butyl ether (MTBE) as a derivative compound in oxygenated gasoline has faced challenges because of environmental concerns. Although there are limited M85 stations in the United States, adapting existing gasoline fueling stations for M85 requires minimal modifications. This flexibility makes it a feasible option compared to alternative fuels like compressed or liquefied natural gas. If local governments, consumers, and retailers decide to develop the market, M85 capability can be added swiftly.

To address the colorless flame of a methanol fire and to avoid cold-start issues in extreme temperatures, M85 is often blended with 15% unleaded premium gasoline. This ensures flame visibility in case of a fire and prevents cold-start problems.

Advantages and disadvantages

• User Transparency: M85, being an alcohol-based fuel, is considered one of the most user-friendly alternative fuels, closely resembling gasoline in purchase and usage. Vehicles running on M85 require only slight modifications to their fuel systems, making them easily adaptable.
• Cost and Flexibility: Modern M85 vehicles have often been offered at no extra cost compared to their gasoline counterparts. The cost per mile is comparable to mid-grade gasoline, and M85 vehicles are designed as flex-fuel vehicles. This means they can run on any mixture of M85 and gasoline, providing a seamless transition based on fuel availability.
• Corrosiveness: Methanol's corrosive nature necessitates changes to the materials in both vehicle and refueling station fuel-handling systems. Special oil additives are required to protect the engine from corrosion.
• Reduced Fuel Efficiency: The richer fuel/air mixture required by methanol means that a given volume of gasoline will provide approximately 70% more distance than the same volume of M85. Manufacturers can compensate for this by installing larger fuel tanks in M85 vehicles.

References