Even oilfields aren’t immune to the ravages of time: A new study finds that as some of the world’s largest oilfields age, the energy required to keep them operating can rise dramatically even as the amount of petroleum they produce drops.
Failing to take the changing energy requirements of oilfields into account can cause oilfield managers or policymakers to underestimate the true climate impacts, Stanford scientists warn.
The new findings, published in the journal Nature Climate Change, have implications for long-term emissions and climate modeling, as well as climate policy. “Current climate and energy system models typically don’t explore the impacts of oil reservoir depletion in any detail,” said study co-author Adam Brandt, an assistant professor of energy resources engineering at Stanford’s School of Earth, Energy and Environmental Sciences. “As oilfields run low, emissions per unit of oil increase. This should be accounted for in future modeling efforts.”
An accurate estimate
In the new study, Stanford postdoctoral researcher Mohammad Masnadi worked with Brandt to apply a new software tool developed at Stanford for calculating greenhouse gas emissions to oilfields around the world that have produced more than 1 billion barrels of oil over their lifetimes, sometimes called “super-giant” oilfields.
Conventional greenhouse gas estimates calculate emissions through a kind of economic reverse engineering, whereby an economic index is used to convert the monetary value of an oilfield’s final products – whether it be processed oil, natural gas or petroleum-based products – into greenhouse gas emissions. “This top-down approach for converting economic values into environmental and energetic costs misses a lot of underlying…