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Ethanol from hemp?


MDJH

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One major criticism of the use of ethanol as a fuel source is that it's "made from corn" and that switching to ethanol would raise corn prices.

 

But what about hemp? According to

, ethanol could be made from hemp as well. If that's true, then shouldn't they be using that instead?
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ethanol can be made from any plant material. high sugary crops such as sugar cane are best. starchy and cellulosic crops are not as good as the starch and cellulose needs to be broken down before it can be metabolised to ethanol.

 

BUT the big arguement people have is that crops for fuel compete withcrops for food. some people misinterpret this to mean its okay to make fuel from crops we don't eat(like above).

 

The real downfall is that the fuel crops compete with the food crops for arable land area. you cannot get round this when using crops for fuel and food, if it needs to be grown then it needs lots of fertile land to do so. as fuel consumption is generally greater than food consumption, the fuel crops would require more area. enough so it would eat up fertile land that could be used for food crops. and as the worlds population is ever expanding, we need to keep expanding our food farms(and fuel farms if we get them).

 

it just means you run out of arable land a few times quicker.

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I recall reading that one further issue with corn-based ethanol is that only a small portion of the plant -- the edible part -- is used to create ethanol, as processing the rest of the plant into ethanol takes a significant amount of energy and isn't very efficient or cost-effective. However, if someone comes up with clever ways to use the non-edible parts of the corn plant, it could be possible to eat corn and have your ethanol too.

 

Dunno if the chemists have gotten anywhere in that goal. Last I read it was still a challenge.

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oh you can utilise the stalks of corn, but you don't get anywhere near the yeild and they are already used for a wide variety of things, they are not simply discarded.

 

the only thing is to get the ethanol from them, you need more time and hence a bigger conversion plant.

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Good points insane_alien. The land area required to meet the US demand for liquid fuels (ethanol and biodiesel) is about 284 thousand square miles, an area 1.2 times the area of Texas. This is using the most efficient plant sources which as you say are sugar beets, sugar cane and palm Oil plants high in sugar or oil content.

 

The size of this required crop area would be a serious contender competing with food production and it puts it completely out of reach in the near term.

 

Hemp is a poor starter material for renewable energy that would only make the situation worse.

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The real downfall is that the fuel crops compete with the food crops for arable land area. you cannot get round this when using crops for fuel and food, if it needs to be grown then it needs lots of fertile land to do so.

What about trees? Would it be worthwhile to make ethanol from them?

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same problem, you need massive amounts of fertile land area in order to grow them meaning it competes with land area for food crops.

 

fertile land is limited. adding more demands to it means something else has to go, whether it be old growth forests or farmland.

 

if we switch to electric cars then we do not need excessive land area. and definitely not arable land either. you can build a nuclear plant pretty much anywaere and it'll supply far more cars for the same area.

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...the big arguement people have is that crops for fuel compete with crops for food. ... The real downfall is that the fuel crops compete with the food crops for arable land area.

Both these reasons is why I like algae farms built in sunny desert lands. Algae is not a food source, and virtually nothing else can grow in deserts. Algae grown "wild" in relatively infertile ocean areas presents problems such as: 1) containing the algae in those areas, 2) protecting the algae from disease and predators, 3) the loss of biodiesel through evaporation and convection, and 4) environmental impact. OTOH, algae farms provide a controlled, artificial environment, and it is easier to separate the biodiesel from algal "broth" of known constitution.

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One major criticism of the use of ethanol as a fuel source is that it's "made from corn" and that switching to ethanol would raise corn prices.

 

But what about hemp? According to

, ethanol could be made from hemp as well. If that's true, then shouldn't they be using that instead?

 

http://www.oilgae.com/energy/sou/ae/re/be/bd/po/hem/hem.html

 

"Hemp plants can produce about half a ton of seeds per Acre but such production is currently relatively expensive. Hemp seeds contain 30% oil, compared to 18% for soybeans, 30% for canola, and 40% for flax. Thus hemp’s Oil content is comparable to that of any other common oil crop. But hemp oil has its problems—the oil degrades even more quickly than other vegetable oils and it is much more expensive than current oil crops. Hemp Biodiesel theoretically can a source of energy. However, it does not appear to offer any significant advantages over other biodiesel sources"

 

Also, here in Canada, there is a huge regulatory aspect. Only certain (Low THC)varieties can be grown, and then only under Govt license, Moving viable seed requires bot shipper and receiver to be licensed. If you are processing it you need a license.

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Both these reasons is why I like algae farms built in sunny desert lands. Algae is not a food source, and virtually nothing else can grow in deserts. Algae grown "wild" in relatively infertile ocean areas presents problems such as: 1) containing the algae in those areas, 2) protecting the algae from disease and predators, 3) the loss of biodiesel through evaporation and convection, and 4) environmental impact. OTOH, algae farms provide a controlled, artificial environment, and it is easier to separate the biodiesel from algal "broth" of known constitution.

So if the algae is grown in deserts... that means it's getting its energy from the sun, right? Why is that more practical than direct solar power?

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  • 4 months later...

So if the algae is grown in deserts... that means it's getting its energy from the sun, right? Why is that more practical than direct solar power?

 

Only because a liquid fuel is produced, easier to intergate into our present transportation options.

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