The argument is that bio ethanol and bio diesel are renewable, and "less bad" than fossil fuels. I'm unconvinced.
According to a major agrochemical producer, Agrii,about 60% of ethanol is produced from maize, 25% from sugar cane, 7% from molasses, 4% from wheat, and the remainder from other grains, cassava or sugar beets.
About 77% of biodiesel is based on vegetable oils (30% soybean oil, 25% palm oil, 18% rapeseed oil) or waste cooking oils (22%).
Rain forest isn't cleared to grow maize, but it is for palm pil used to make bio diesel.
Ethanol is also produced from petrochemical plant derived chemicals where it is manufactured by reacting ethene with steam. The catalyst used is solid silicon dioxide coated with phosphoric(V) acid. The reaction is reversible. ... By removing the ethanol from the equilibrium mixture and recycling the ethene, it is possible to achieve an overall 95% conversion. I have not been able to find out what percentage of ethanol is produced this way.
Higher-ethanol gasoline blends still produce significant levels of air pollution, reduce fuel efficiency, jack up corn and other food prices, and have been treated with skepticism by some car manufacturers for the damage they do to engines. Growing corn to run our cars was a bad idea 20 years ago and is still a bad idea. US is the driver, where maize growing is subsidised by Government to appease the eco. lobby who want cars to run on 50/50 ethanol/gasoline. in my view it is more stupid than battery electric cars.
