by Flow » Wed 23 Nov 2005, 01:12:39
$this->bbcode_second_pass_quote('oilmangonegreen', 'W')hy has everyone suddenly started thinking in terms of dollars? All I was trying to say is that there is no point in exploiting tar sands/shales (or anything else) if the energy required for extraction is equal to or more than the energy obtained by extraction. And it doesn't matter whether the energy required for extraction is from oil, gas, nuclear, wind, solar, whatever. It's mad to continue if energy input > energy output ... we'd be better off using that energy directly for other purposes. Whether the value of oil is 10 dollars/barrel (sorry, no dollar sign on my Norwegian computer) or 100 dollars/barrel is irrelevant. But then, I'm an engineer, not an economist.
I think the discussion has turned to price because to leave it to a pure EROEI is deceiving to say the least. For example, if something that produces a good amount of oil by using an energy source that is more abundant and cheaper than that oil, the energy required could be high but the end result is a product that is not only more profitable but in shorter supply.
For example, if a lot of the “energy” to extract and produce oil from say Tar Sands or Oil Shale comes from natural gas, coal or electricity (which is considerably cheaper than oil/gas as a source of energy), the EROEI ratio could be very close to 1:1 but the end product (oil) could still be sold for a profit and still be considerably higher than the total amount of oil that went into the process. I only use Tar Sands and Oil Shale as an example so please, do not focus on that part of the argument. I guess a better example would be coal to oil liquefaction where electricity is the major energy source in getting the coal out of the ground and natural gas is the major energy source in heating the coal. These energy sources are considerably less expensive that the resulting product – synthetic oil yet the EROEI on this process is not the best out there. But when talking about how much fossil fuel is required vs. how much you get out, the ratio is much, much larger.