Global patterns of energy supply and consumption are unequal, with some countries having a surplus energy and others having a deficit.
Saudi Arabia, Russia and the USA are the top oil producers, accounting for around 50% of known oil reserves.
Around 80 countries have coal reserves, with enough coal left to last for another 130 years.
Russia, Iran and Qatar have the largest natural gas reserves.
Just under half of the UK's natural gas comes from the North Sea, although production has decreased as profits have fallen.
Globally, there is enough natural gas to last for around 50 years.
Kazakhstan, Canada and South Africa have the largest uranium reserves, a non-renewable resource used to generate nuclear power.
Uranium reserves are expected to last for another 80 years.
The top oil producers are Saudi Arabia, Russia, USA, Iran and Mexico.
The energy mix in the UK reflects its strong economy and the variety of energy sources needed for industrial production, electrical production, transport, and domestic use.
Energy consumption in developed countries is high, but stable as populations are steady and new technologies help to conserve energy.
As the UK invests in renewable energy, it will be able to be more self-sufficient in its energy supply.
The growth in energy consumption will largely take place in developing countries.
The National Grid generates the electricity used in the UK, with sources varying from day to day due to variations in demand and the availability of certain types of energy such as wind and solar power.
Countries close to plate boundaries can generate geothermal power.
Global population is increasing and everyone uses energy, leading to a greater consumption of energy.
Global energy consumption is estimated to increase by 27% between 2020 and 2040.
Nuclear power requires uranium which the UK does not have, so this also has to be imported.
Most of the oil and coal the UK uses has to be imported from other countries, however the UK secures some of its gas supply from the North Sea.
The UK uses a mixture of fossil fuels, nuclear energy, and renewable energy.
The development of new technologies means that more people are using energy.
Wet places with steep relief can generate hydroelectric power.
Economic reasons, such as factories and offices being run using energy, contribute to increasing energy consumption.