The North Sea is a good example of recoverable reserves exceeding first estimates.When BP opened the Forties field,they reckoned in 20 years it would be dry.That was in 1975,but it's still going strong 33years later and there's about another 30 years left.This because new methods of extracting oil,and perhaps the estimates were a little conservative.Also a large number of North sea fields were plugged just after they were discovered because they were uneconomic to develop.However will Brent crude at $100 a barrell,it's a different story now.
The days of cheap oil are long gone.Consumption is going up with China and India using a lot more than a decaded ago.We should be looking at different energy forms of powering cars,fuel cells for example.We should be saving oil instead of wasting it.Perhaps the bus drivers in DB could switch off their engines when standing still.To save fuel,and never mind the a/c.