Despite all the hopes of sun and wind enthusiasts, the real revolution in the energy world has been driven by old-style fossil fuels. Shale gas now dominates global energy policy.
Despite all the hopes of sun and wind enthusiasts, the real revolution in the energy world has been driven by old-style fossil fuels, not by renewables. Shale gas changed power relations in the fossil fuel world, and its impact is going to affect economies and geopolitics. Unlike traditional natural gas, shale gas is not trapped in large reservoirs but in smaller rock formations that have to be penetrated through hydraulic “fracking.” The drilling technology has been refined in the last twenty years and has allowed for extensive gas production in North America.
The price difference between (lower) American oil prices and (higher) European oil prices can be explained by the presence of shale gas in the US. The American WTI blend is some twenty dollars cheaper than the old continent's Brent blend.
Gas is no direct substitute for oil: it takes time and money to switch energy sources. You might want to get a good run out of your old car before switching to a new (and possibly gas-powered) model with better mileage. Or you might wait before switching your heating system at home from oil to gas.