|Global supply of liquid hydrocarbons from all fossil resources and associated costs in dollars (top) and GHG emissions (bottom). Click to enlarge.|
The increasing use of substitute fossil-based liquid hydrocarbons—either unconventional crude oils or synthetic liquid fuels (synfuels)—will dramatically increase global greenhouse gas emissions unless mitigating steps are taken, according to a new study by researchers at UC Berkeley.
The authors argue that the global energy system is in the early stages of a transition from conventionally produced oil to a variety of substitutes, bringing economic, strategic, and environmental risks. They further argue that without appropriate policies, tradeoffs between these risks are likely to be made so as to allow increased environmental disruption in return for increased economic and energy security.
Their work is reported in the paper “Risks of the Oil Transition,” published in the new Institute of Physics open-access electronic-only journal, Environmental Research Letters (ERL).
Liquid fuels for transportation are increasingly coming from a wide range of sources other than conventional petroleum. We call this the oil transition and we conclude that the environmental risks associated with this transition are much bigger than the risk to a country’s economy or the security of their fuel supply.—Alex Farrell, lead author
Under the category of substitutes for conventional petroleum (SCP), the authors consider synthetic crude produced from oil sands and oil shale, heavy oil production, and Fischer-Tropsch synthetic fuel production.
We have calculated that production of fuels from low-quality and synthetic petroleum, such as tar sands, could have greenhouse gas emissions 30%-70% greater than the emissions from conventional gasoline. Tar sands are already being used as a source for gasoline, with over one million barrels refined each day in Alberta, Canada. With oil selling for $60/barrel on the international market, the $30/barrel production cost for tar sands is no longer an obstacle to production as it used to be.—Alex Farrell
The authors suggest approaches that can mitigate all three risks, beginning with the diversification of energy supply and including demand reduction and better transportation planning.
Fossil-based SCP technologies with CCS [carbon capture and storage] could provide supply diversity in the near term if adequate investments were made. Because of the fuel-related GHG emissions, fossil SCPs might be appropriate only as a short-term response, although the path dependence of energy system investments suggests there may be no such thing as a purely short-term response.
The true challenge of the oil transition is to develop and deploy environmentally acceptable energy technologies (both supply and demand) rapidly enough to replace dwindling conventional oil production and meet growing demand for transportation energy.
Because of the large environmental and security externalities involved, markets alone will not respond to this problem, so government policies to manage the all three risks of the oil transition are needed now.
“Risks of the oil transition”; A E Farrell and A R Brandt; Environmental Research Letters, Volume 1, Number 1, October-December 2006