I think $2.50 would do it. The problem with this technology is it costs $35/bbl, while the middle east can produce for $4 (yes, they ARE raping us right now). I'm sure Shell's reluctant to pursue this because they could be drowned in Saudi oil at cheap prices at any time.
We need to find a way to stabilize prices and supply, then drain middle east oil until it's scarce enough that it costs them $35/bbl.
I'd go for invading the middle east, taking their oil, and putting their population on food stamps and required birth control. If the left is going to accuse us of such a thing, we may as well really do it.
This is a VERY important point. It isn't demand pressure (China) that is pushing oilprices up, it is OPEC and aholes like Sorros dicking around with futures. The Soddies got the ball going, and seem to have lost control of it, Sorros is cheerleading it for political power. I just hope the bubble pops before sorros gets out, and when the Soddies have the spiggets wide open.