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Re: Oil....Gold prices Will Go Up This Week!
If you look at a human body then the food you eat (according to a doctor I asked a while ago) is about 10 (megajoules) each day give or take a bit depending on size, gender, occupation etc.
Now, if people ran on petrol then we would each need about 100 litres per year to supply this energy. So, all the food we eat in a year supplies enough energy to fill the tank of a six cylinder car one and a half times each YEAR. Enough to drive a Falcon about 700km or about one fortnight's typical use.
So, we double the food production and use that to run our cars for 2 weeks a year. Of course, converting that food to ethanol would lose some of this energy and then there's all the (oil) energy that goes into growing and transporting the food. And natural gas to produce the nitrogen fertilizers etc.
And then we need fuel for buses, trucks, aeroplanes...
It makes good sense to make ethanol from agricultural and forestry wastes. Very good sense indeed. But we're just not going to be able to make anywhere near enough to use it as a mass replacement for petrol.
The problem is one of scale.loakglen said:Thanks for the info Han.
Ethanol can be used as a complete replacement for diesel IMO. I don't know what the numbers would look like though. New engines would be needed for tractors and trucks but given the amount of compression you can apply to ethanol the torque output should be sufficient to power a truck easily. That said, with new engines designed for ethanol the lifespan of a massive low revving high-torque engine shouldn't be much different.
If you look at a human body then the food you eat (according to a doctor I asked a while ago) is about 10 (megajoules) each day give or take a bit depending on size, gender, occupation etc.
Now, if people ran on petrol then we would each need about 100 litres per year to supply this energy. So, all the food we eat in a year supplies enough energy to fill the tank of a six cylinder car one and a half times each YEAR. Enough to drive a Falcon about 700km or about one fortnight's typical use.
So, we double the food production and use that to run our cars for 2 weeks a year. Of course, converting that food to ethanol would lose some of this energy and then there's all the (oil) energy that goes into growing and transporting the food. And natural gas to produce the nitrogen fertilizers etc.
And then we need fuel for buses, trucks, aeroplanes...
It makes good sense to make ethanol from agricultural and forestry wastes. Very good sense indeed. But we're just not going to be able to make anywhere near enough to use it as a mass replacement for petrol.