United States, the world's largest oil producer

The world oil supply also grew as never before in 2014 (2.1 million barrels per day), according to statistics on energy BP. This increase was mainly due to growth of 1.6 million barrels per day of US production.

According to the report, this is the first time a country to extending their supply by more than 1 million barrels a day for three consecutive years.

"The United States has surpassed Saudi Arabia and Russia as the world's largest oil producer for the first time since 1975," said Bob Dudley, CEO of BP.

"The implications of the US shale revolution are profound," he said. For example, the United States has significantly reduced its imports, to the point of giving China the largest importer place.

And that despite the economic slowdown caused the increase in Chinese demand was only 2.6% in 2014, far less than the average annual progress of 6.6% in the previous 10 years.

Oil shale is an unconventional technique that involves injecting water at high pressure to fracture rocks located at depths of between 1,500 and 2,400 meters oil extracted by "fracking," or hydraulic fracturing.

This technique has expanded the possibilities of extracting oil to many other countries and is a threat to the dominance of the traditional producers.