[QUOTE=sweeteviljesus]
Has anyone heard of using old oil wells for geothermal energy extraction? Is this the same as “hot rocks”? I read an article about it, but I don’t remember where.
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I suspect you may be conflating two things here; in general places where oil is are not geo-thermally active, for obvious reasons. If you see the two articles I links a few posts ago, you have to drill down a long way (~4km) to get to hot rocks (except the huge one found in South Australia recently, that’s unusually shallow), deeper than most oil wells. Most of the cost is in the drilling.
[QUOTE=Balthisar]
the price of tequila would skyrocket again like back in 2001.
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DEAR GOD…NO!!! :eek: :eek: 
[QUOTE=Hypno-Toad]
One approach to improve the system is genetically altering the plants so that every part of the plant is usable. This really helps but I have not heard if it has been successful or not.
Martin, you seem to have hit the nail on the head on the confusing nature of the issue. The straight dope on bio-fuels seems to depend on who you want to believe. And yes, it is highly debated topic that gets spun very heavily.
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I can’t post on it because I’ve signed an NDA, but my company is right now designing an ethanol production plant which appears to be substantially energy positive. However, the capital cost does not appear to me that it will have a payback any time soon unless gasoline stays near $4 a gallon or higher. Nonetheless, it’s serious enough that folks are thinking to break ground in less than 3 months.
When I was in Europe last week, I met with a large company which is betting the farm on biodiesel production from rapeseed, and their calculations are showing a very large net energy production from the process. Thanks to the regulatory environment they’re in, they feel like they themselves can eventually supply 15% of their entire country’s motor fuel, although they will need to import rapeseed from other countries, such as the US…and if the US is busy making its own biodiesel, then it may be a case of too much demand for too little raw material. I wasn’t there to talk about biofuels, so I didn’t get any details of their process, although I did get to tour their laboratory and see and smell biodiesel in different levels of production. No souvenirs, though. Damn.
[QUOTE=DrDeth]
Chernobyl will never happen again just like the Hindenburg disaster will never happen again. They no longer use either technology.
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But to say Chernobyl will never happen again is not to say a nuclear accident can never happen again.
[QUOTE=Askance]
T
The scalable source of geo-thermal I was thinking of is what they are calling “hot rocks”; here in Australia for instance it has turned out that a large part of the state of South Australia (50% larger than Texas) is underlain by vast areas of hot rock, and pretty much all you need to do is pump water down to it and pipe the steam up.
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sorry the greens would never let you use geothermal as the earths core is heated by nuclear energy. 
[QUOTE=Una Persson]
When I was in Europe last week, I met with a large company which is betting the farm on biodiesel production from rapeseed, and their calculations are showing a very large net energy production from the process. Thanks to the regulatory environment they’re in, they feel like they themselves can eventually supply 15% of their entire country’s motor fuel, although they will need to import rapeseed from other countries, such as the US…and if the US is busy making its own biodiesel, then it may be a case of too much demand for too little raw material. I wasn’t there to talk about biofuels, so I didn’t get any details of their process, although I did get to tour their laboratory and see and smell biodiesel in different levels of production. No souvenirs, though. Damn.
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I’ve heard that soybeans give a much greater return than corn in terms of bio-diesal (or ethanol. Damn memory).