Higher Mixed Alcohol Fuel
Ethanol
Feedstocks
All types of gaseous, solid or liquid carbonaceous materials (garbage, trash, biomass, sludges, old tires, etc.) Cultivated (food) crops
Cost of production Under $1 per gallon, profitable without subsidies due to reliance on abundant waste/fossil carbons Over $1 per gallon, questionable profitability due to end of subsidy, cost of corn due to drought
Quantity for production Unlimited volumes using diverse feedstocks Determined by agri-produced feedstock sources
Time for production 24×7 continuous thermal technology processes 4 to 7 day batch fermentation utilizing acidic enzymes, genetically-engineered biobugs or yeasts
Transport considerations Uses existing oil and fueling infrastructure including pipelines where higher mixed alcohols can be mixed with crude oil or refined derivatives Separate tanker shipments between distillery, refinery or blending ports
Blending characteristics Midrange 4.61 RVP, closer to gasoline which is 7.8 to 9.4 RVP Lower 2.0 RVP
BTU value 92,000-96,000 BTU per gallon depending on catalyst/fuel blend 75,500 BTU per gallon
Octane value 109-138* Depending on catalyst/fuel blend 107
Oxygen content 34% 33%
Biodegradable yes yes
Emissions/CO 37-69% reductions 13-33% reductions
Emissions/VOC 18% reduction 5% reduction
Global applications yes specific to agricultural regions
Commercial scalability yes – unlimited limited by feedstock availability
Process byproducts
Co-generated electricity, distilled water, inert slags when solids are gasified CO2 fermentative emissions, Distillers grains sold as animal feed
Miles per gallon when blended with gasoline Increases mileage and engine torque because of increased combustion efficiencies Typically slightly reduced mileage
Considerations when blending with diesel Blends into diesel from 5% to 10% by volume. Eliminates black sooty exhaust. Can provide 20%+ greater fuel economy in non-adjusted diesel engines. No phase separation in cold conditions. Ethanol not utilized for blending with petroleum-derived diesel fuel. Ethanol has lower RVP and BTU values and may phase separate in cold conditions.
Considerations in cold weather Stays blended into petroleum fuels without phase separation. As a neat fuel, higher mixed alcohols integrates about 5% gasoline volume for increased vapor pressure for cold starts. As a neat fuel, ethanol has cold start problems with only 2.0 RVP of vapor pressure. Ethanol/gasoline blends work better with fuel injection systems versus carburetors.