At least partially because it’s not actually that good or sustainable. Studies have shown that in many cases, when accounting for land use etc, it’s actually quite a bit worse for the environment to use than normal gasoline. The main reason that it’s so ubiquitous in some places is that it’s subsidized as an indirect way to support farmers (this is why in the Midwest it’s the cheapest option at every pump).
Ethanol is renewable because it can be made from any sugar source, and plants the produce sugar can be regrown, but it’s not sustainable as a large-scale fuel source because the amount of land necessary to produce enough corn/sugarcane/etc. to fuel all of our vehicles would be insane. Not to mention the chemical, labor, and energy inputs to produce that much ethanol would also be massive. It’s only economically viable to use ethanol for fuel in the US currently because of massive government subsidies given to corn farmers.
Ethanol absorbs water from the atmosphere, and is hard to separate. Ethanol and water form a homogenous mixture; the water doesn’t settle to the top or bottom. This means you can’t design tanks to avoid small water buildup (if you don’t pull from the very bottom of the tank, you’ll avoid water that’s settled there). Water will just accumulate in your fuel, and will do so faster than gas/diesel.
It also increases the energy required to produce it; you can’t distill ethanol past ~95% (meaning there’s still 5% water) conventionally (this is why Everclear is ‘only’ 190 proof and not 200). Getting that last 5% out requires a bunch more work.
Just generally the answer is “water is more of an issue for ethanol than for oil”.
Another disadvantage is that ethanol soaks up water easily, so that its storage and transport are more difficult than with other fuels. And anything difficult = more expensive/resource intensive.
Whilst ethanol produced 4% less CO2 compared to gasoline when burnt, it also produces 15 to 20% more during fermentation. So it is not so environmently friendly
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“can be made” and “can be made easily on an industrial scale” are two VERY different things.
At least partially because it’s not actually that good or sustainable. Studies have shown that in many cases, when accounting for land use etc, it’s actually quite a bit worse for the environment to use than normal gasoline. The main reason that it’s so ubiquitous in some places is that it’s subsidized as an indirect way to support farmers (this is why in the Midwest it’s the cheapest option at every pump).
Ethanol contains roughly one-third less energy per gallon than gasoline meaning you get less miles per gallon
It has to be farmed, which takes a lot of fuel. It has to be distilled, which takes a lot of energy.
Ethanol is renewable because it can be made from any sugar source, and plants the produce sugar can be regrown, but it’s not sustainable as a large-scale fuel source because the amount of land necessary to produce enough corn/sugarcane/etc. to fuel all of our vehicles would be insane. Not to mention the chemical, labor, and energy inputs to produce that much ethanol would also be massive. It’s only economically viable to use ethanol for fuel in the US currently because of massive government subsidies given to corn farmers.
Ethanol absorbs water from the atmosphere, and is hard to separate. Ethanol and water form a homogenous mixture; the water doesn’t settle to the top or bottom. This means you can’t design tanks to avoid small water buildup (if you don’t pull from the very bottom of the tank, you’ll avoid water that’s settled there). Water will just accumulate in your fuel, and will do so faster than gas/diesel.
It also increases the energy required to produce it; you can’t distill ethanol past ~95% (meaning there’s still 5% water) conventionally (this is why Everclear is ‘only’ 190 proof and not 200). Getting that last 5% out requires a bunch more work.
Just generally the answer is “water is more of an issue for ethanol than for oil”.
It’s also less energy dense.
Another disadvantage is that ethanol soaks up water easily, so that its storage and transport are more difficult than with other fuels. And anything difficult = more expensive/resource intensive.
Whilst ethanol produced 4% less CO2 compared to gasoline when burnt, it also produces 15 to 20% more during fermentation. So it is not so environmently friendly