A second shale revolution is in prospect, in which cleaner and more efficient ways are being found to squeeze oil and gas out of rocks.
THE cliffs at Kimmeridge, on England’s south coast, have on occasions been known to smoulder or even burst into flames in hot weather. That is because, unlike the famous white chalk cliffs of Dover, they are made of oil shale, a soft rock that has hydrocarbons trapped in its pores. The world’s oil-shale beds may contain the equivalent of up to nine times as much oil as all of its conventional wells.
Confusingly, oil shale has nothing to do with fracking, a technique for extracting oil and gas from a different sort of shale through horizontal drilling and hydraulic fracturing. America is blessed with prodigious quantities of both types of shale. Its fracking pioneers have successfully exploited one type, transforming the country’s energy supply. But hitherto, squeezing the energy out of oil shale has generally proved uneconomic, and even more environmentally unsound than other forms of fossil-fuel extraction.
However, a second shale revolution is in prospect, in which cleaner and more efficient ways are being found to squeeze the oil and gas out of the stone. The Jordanian government said on June 12th that it had reached agreement with Enefit, an Estonian company, and its partners on a $2.1 billion contract to build a 540MW shale-fuelled power station. Frustratingly for Jordan, as it eyes its rich, oil-drenched Gulf neighbours, the country sits on the world’s fifth-largest oil-shale reserves but has to import 97% of its energy needs.
In Australia, Queensland Energy Resources, another oil-shale company, has just applied for permission to upgrade its demonstration plant to a commercial scale. Production is expected to start in 2018. Questerre Energy, a Canadian company, also said recently that it would start work on a commercial demonstration project, in Utah in the United States.
In all these projects, the shale is “cooked” cheaply, cleanly and productively in oxygen-free retorts to separate much of the oil and gas. In Enefit’s process the remaining solid is burned to raise steam, which drives a generator. So the process produces electricity, natural gas (a big plus in Estonia, a country otherwise dependent on Russian supplies) and synthetic crude, which can be used to make diesel and aviation fuel. The leftover ash can be used to make cement. Enefit’s chief executive, Sandor Liive, says his plants, the first of which started production in December 2012, should be profitable so long as oil prices stay above $75 a barrel (North Sea Brent oil was around $113 this week). […]
Some of the world’s biggest energy firms have also experimented with mining and processing oil shale, only to give up, after finding that it took so much energy that the sums did not add up. However, Shell says it is making progress with a new method it is trying, also in Jordan, in which the shale is heated underground with an electric current to extract the oil.