Getting past the Ethanol powerful lobby group is the problem. Biobutanol Would be great for 2 cycle equipment: https://www.biofuelsdigest.com/bdigest/2017/04/05/butanol-vs-ethanol-as-a-fuel-component/ http://www.reuk.co.uk/wordpress/biomass/butanol-vs-ethanol-fuel-of-the-future/ "Butanol can be made from crop waste or from ethanol made from crop waste, sugar beet, corn, wheat etc, it carries the same amount of energy as petrol and so does not reduce mileage, it is not corrosive to engines and does not separate from petrol in the presence of water and so it can be used in much higher concentrations without engine modification. Butanol is made by fermentation and distillation of biomaterial, as is ethanol, but the process is a bit different. As making butanol directly is more expensive and complex than making ethanol (which is made using existing beverage alcohol making technology), and since there is already of lot of ethanol manufacturing infrastructure in place, research has been focussed on finding ways to convert ethanol into butanol. This will enable existing ethanol plants to be very cheaply converted into butanol plants, and for the butanol output to be commercially viable as a fuel..........." https://www.afdc.energy.gov/fuels/emerging_biobutanol.html Benefits Biobutanol is an alternative to conventional transportation fuels. The benefits of biobutanol include: Higher energy content—Biobutanol's energy content is relatively high among gasoline alternatives. However, biobutanol's energy density is 10%–20% lower than gasoline's energy density. Lower Reid vapor pressure—When compared with ethanol, biobutanol has a lower vapor pressure, which means lower volatility and evaporative emissions. Increased energy security—Biobutanol can be produced domestically from a variety of feedstocks, while creating U.S. jobs. Fewer emissions—Carbon dioxide captured by growing feedstocks reduces overall greenhouse gas emissions by balancing carbon dioxide released from burning biobutanol.