pogo wrote:
Dusty wrote:
Most people do not realise that an oil well goes "Dry" with as much as 60% of the reserve still in the ground! the point is that it becomes an energetic nonsence to continue to extract the oil. Indeed many wells spend the last 10% or so of their production operating at an energy defecit
Did you read the comment made by the chairman of BP a couple of days ago? He's of the opinion that recent rapid developments in extraction technology will return large number of these moribund wells to profitable production - and he was basing that profitability on a fall in price to $30 - $40 per barrel over the next 5 years caused by it... I hope he's right!

I have no doubt that this is correct, However, I would be interested in knowing what the "Energy Ratio" for these advanced process are (Past sugestions for advanced extraction include use of detergents/solvants, Steam, Electrical heating (!) and even setting underground fires!)
Note, I am not saying at any point that Oil is going to become "Unavailable" any time soon, simply that it will cease to be an energy "Source" and that to extract the remaining opil reserves will require a substantial energy input in the form of, (say), Nuclear derived heat or electricity!
This does not nececarrily mean that Oil fuels willl become massivly expensive either. But it *does* mean that we will have to find an alternative "Source" of energy to replace that which we currently get from oil (and gas). To give you an idea as to what this is going to mean, For the UK it would take arround 200 Sizewell B's to replace the energy we currently get from fossil fuels!
PLEASE dont try to tell me this is going to all come from a scattering of remotely sited wind farms!
The big problem is that we really must "Plan ahead" for this and not wait for the shortages before we take action otherwise things are going to get really very hard (Remember the drop in oil production that triggererd the "Oil Crisis" of the early 70's was really quite small! and was political, and therefore sudden. I imagine that the "Crisis" in the future will be similar in nature and simmilarly disruptive! w
We really should be building our alternatives now while it is easy)