Oil consists mainly of a mixture of hydrocarbons, resulting from the decomposition and transformation of plant and animal organic matter over millions of years. This process takes place deep underground and requires a specific environment. Because of their low density, a large part of the hydrocarbons thus formed escaped from their source rock and migrated towards the surface of the earth. Where there were watertight layers on top of suitable geological formations called anticlines, this migration was halted, leading to the accumulation of hydrocarbons in reservoir rocks and thus to the creation of conventional oil and gas deposits as we know them today. However, certain source rocks are not porous enough to allow hydrocarbons to escape from them. In this case one speaks of oil shale, recovery of which requires particularly costly, unconventional methods. Where hydrocarbons have reached the earth's surface, the light elements have evaporated, leading to the formation of layers of natural bitumen and asphalt, which already in ancient times were extracted and used, for example, as construction mortar or to make the hulls of boats waterproof. Recovery of the deposits located at great depths requires the boring of oil wells – on land or at sea (on oil rigs) – to extract the oil. This hydrocarbon is transported by tankers, pipelines, tank cars or tank trucks. It is processed into different finished products in refineries. The products used as energy sources can be divided roughly into two main categories: heating fuels (heating oils, petroleum coke) and fuels (gasoline, diesel, kerosene). Oil is also used in the chemical industry, particularly for the production of plastics.
It was not until the mid-19th century that recovery of oil began to boom. After the Second World War, it very soon replaced coal in many areas (transport, heating) because it is easier to extract, transport, store and use and because it pollutes less. Moreover, between 1945 and 1973 – before the 1st oil crisis – this hydrocarbon was very cheap. Since 2005, the price of a barrel of crude oil has remained constantly above the 50 dollar mark (US$/bbl). In the USA and Canada, this high price level has encouraged large-scale use of hydraulic fracturing – a complex and expensive production technique – to recover shale oil and gas deposits. Recovery of these unconventional reserves has delayed the onset of peak oil, that is, the time when global oil production will reach its maximum. Assuming that this production remains at the current level, proven oil reserves (two thirds of which are in the Middle East) would be sufficient to meet global requirements for more than 52 years according to BP's Statistical Review of World Energy. These statistics show that with a share of 19.9% of world consumption, it is the USA that consumed the most oil in 2014, ahead of the EU (EU-28: 14.1%), China (12.4%), Japan (4.7%) and India (4.3%). The OECD countries' share fell to 48.3%. The largest oil producers were Saudi Arabia (12.9%), Russia (12.7%), USA (12.3%), China (5.0%) and Canada (5.0%). As for the OPEC countries, again according to BP, they met 41% of the world's oil requirements (taking into account natural gas liquids or condensates produced by the cartel).
Over the past 10 years, the oil market has been marked by significant price fluctuations. In response to the surge in demand from China and Southeast Asia in particular, crude oil prices soared to the record level of US$ 147/bbl in early July 2008, before the global economic crisis – one of the worst ever recorded – pushed them down to below the US$ 35/bbl mark six months later. After a two-year recovery phase, the oil market experienced a period of relative stability from January 2011 to June 2014, with crude oil prices slightly above US$ 100/bbl. Prices fell again sharply during the second half of 2014 and in 2015, in an environment of over-abundance on the world oil market. There were three main reasons for this: the weakness of global demand, the shale oil boom in the USA and OPEC's refusal to cut its production ceiling. In mid-January 2016, crude oil prices fell below the US$ 30/bbl mark, for the first time since early 2004.
In Switzerland, as in most of the OECD countries, the two oil crises in the 1970s highlighted the risks of a unilateral energy supply. Since then, the share of petroleum products in our country's energy consumption has fallen from 80% in 1973 to 51.5% in 2014 (heating fuels: 15.4%; fuels: 36.1% and the oil intensity of the Swiss economy decreased by almost half – as in the other industrialized countries – due mainly to the growing importance of the tertiary sector. This trend is likely to continue. However, in absolute terms, Swiss oil consumption dropped by only 11% to about 10 million tons/year between 1975 and 2014 (0.3% of world requirements). That is why the Federal Council is envisaging more vigorous measures to reduce consumption.