by Richard Douthwaite. In a widely-circulated article in September 2011, Chris Skrebowski, who runs a peak oil consulting firm and was editor of the Petroleum Review for eleven years until 2008, argued that there are two forms of oil peak. One is, or will be, caused directly by depletion – the oil is no longer in the ground in sufficient quantities for producers to be able to maintain production. The other is the economic oil peak, which he says is the “price at which oil becomes unaffordable to consume and therefore to produce.” Is this assessment realistic?