The UK's indigenous oil supplies are declining. Consequently, the UK imports most of the oil it needs. In 2009, 66.5% of the UK's oil supply was imported. One kilogram of oil contains between 42 and 44 megajoules of energy (an energy density of 42–44MJ/kg). This means that the quantities required to generate electricity on a national scale take up a lot of space, which makes it problematic to transport and to stockpile to guard against supply disruptions.
Relying on imports to supply a large proportion of the country's oil exposes the UK to potential security of supply issues, including fluctuating market prices and disruptions to fuel supplies caused by geopolitical disturbances (such as damage to pipelines).
These are the security of supply challenges facing oil. Read about the possible solutions.