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Sweet smell can also be from running ethanol-rich fuels.

by pitaj 5y ago

rbanffy 5y ago
Which is kind of interesting in this regard. Brazil converted a large portion of its passenger car fleet to ethanol and it seemed a better overall fuel, to the point some sportier models had only ethanol versions. Wouldn’t ethanol be an adequate substitute for avgas with property adapted engines?
- bityard 5y ago
  Ethanol is a terrible substitute for gasoline. It has something like 70% the energy density of gas, it readily absorbs water from the air, which means it also corrosive. The main reason it works in Brazil is because they can make it cheaply from sugar cane. In the U.S., ethanol is just a highly inefficient subsidy for corn farmers.
  - GekkePrutser 5y ago
    The moisture thing alone would be a deal-breaker for avgas. You really don't want to have engine trouble mid-flight and avgas has special anti corrosion compounds afaik. We always topped up the aircraft tanks every time to minimise condensation.
  - rbanffy 5y ago
    > It has something like 70% the energy density of gas That's true - when running on ethanol, range is shorter. OTOH, it allows higher compression than gasoline - which is why some cars came with ethanol-only engines. When disassembling engines, we also note there is much less, if any, deposits. > also corrosive. This was solved (in cars) in the late 1970's. > In the U.S., ethanol is just a highly inefficient subsidy for corn farmers. Maybe not worth it for cars (especially now that we have viable batteries for EVs) but these are different markets.
  - lathiat 5y ago
    This video was crazy, making ethanol from Corn provides something like 1% of the power of the sun hitting the square meter of farm used for it. Meanwhile using tonnes of water, space, and other things. It's basically a terrible idea over-all given alternatives like electricity and solar power. And it mostly only works because its government subsidised. But watch the video for the full story: Real Engineering - Why Biofuels Are Terrible https://www.youtube.com/watch?v=OpEB6hCpIGM https://www.youtube.com/watch?v=OpEB6hCpIGM
    - ReactiveJelly 5y ago
      Ag subsidies in the US are pretty wild. One study said that 75% of the price of dairy was subsidized. The fact that I haven't heard of any other studies (or that you even need a study to determine such a number) is a bizarre red flag by itself.

Sweet smell can also be from running ethanol-rich fuels.

by pitaj 5y ago

Sweet smell can also be from running ethanol-rich fuels.

Which is kind of interesting in this regard. Brazil converted a large portion of its passenger car fleet to ethanol and it seemed a better overall fuel, to the point some sportier models had only ethanol versions. Wouldn’t ethanol be an adequate substitute for avgas with property adapted engines?

bityard 5y ago
Ethanol is a terrible substitute for gasoline. It has something like 70% the energy density of gas, it readily absorbs water from the air, which means it also corrosive. The main reason it works in Brazil is because they can make it cheaply from sugar cane. In the U.S., ethanol is just a highly inefficient subsidy for corn farmers.
- GekkePrutser 5y ago
  The moisture thing alone would be a deal-breaker for avgas. You really don't want to have engine trouble mid-flight and avgas has special anti corrosion compounds afaik. We always topped up the aircraft tanks every time to minimise condensation.
- rbanffy 5y ago
  > It has something like 70% the energy density of gas That's true - when running on ethanol, range is shorter. OTOH, it allows higher compression than gasoline - which is why some cars came with ethanol-only engines. When disassembling engines, we also note there is much less, if any, deposits. > also corrosive. This was solved (in cars) in the late 1970's. > In the U.S., ethanol is just a highly inefficient subsidy for corn farmers. Maybe not worth it for cars (especially now that we have viable batteries for EVs) but these are different markets.
- lathiat 5y ago
  This video was crazy, making ethanol from Corn provides something like 1% of the power of the sun hitting the square meter of farm used for it. Meanwhile using tonnes of water, space, and other things. It's basically a terrible idea over-all given alternatives like electricity and solar power. And it mostly only works because its government subsidised. But watch the video for the full story: Real Engineering - Why Biofuels Are Terrible https://www.youtube.com/watch?v=OpEB6hCpIGM https://www.youtube.com/watch?v=OpEB6hCpIGM
  - ReactiveJelly 5y ago
    Ag subsidies in the US are pretty wild. One study said that 75% of the price of dairy was subsidized. The fact that I haven't heard of any other studies (or that you even need a study to determine such a number) is a bizarre red flag by itself.