k (kilo) | 1,000 |
(thousand), or 10^{3} |

M (mega) | 1,000,000 |
(million), or 10^{6} |

G (giga) | 1,000,000,000 |
(billion), or 10^{9} |

T (tera) | 1,000,000,000,000 |
(trillion), or 10^{12} |

P (peta) | 1,000,000,000,000,000 |
(quadrillion), or 10^{15} |

E (exa) | 1,000,000,000,000,000,000 |
(quintillion), or 10^{18} |

bbl | barrel – standard quantity of oil equaling 159 liters |

bcm | billion cubic meters or billion m^{3} |

bpd | barrels per day |

BOE | Barrels of Oil Equivalent. 1 BOE = 41.868 GJ |

°C | degree Celsius |

cm | centimeter |

EJ | exajoule = 10^{18} joules |

GJ | gigajoule = 10^{9} joules |

Gt | gigatonne = 10^{9} metric ton |

Gtpa | ‘gigatonne per annum’, gigatonne per year |

GW | gigawatt = 10^{9} watts (see watt) |

GWh | gigawatt hour = 10^{9} watt hour |

ha | hectare – 10,000 m^{2} |

hr | hour |

J | joule = 1 kg x 1 m^{2}/s^{2}, 1 J is the amount of energy spent when a force of one newton is applied over a displacement of one meter |

kg | kilogram = 1,000 gram |

km | kilometer = 1,000 meter |

kt | kilotonne = 1,000 metric tonnes |

kW | kilowatt = 1,000 watts (see watt) |

kWh | kilowatt hour |

L | 1 liter = 1,000 cc (cm^{3}), 1 L of pure water has a mass of 1 kg at 25°C |

m | meter |

m^{2} |
square meter |

m^{3} |
cubic meter |

mbd | million barrels per day |

Mio | million, mega |

MJ | megajoule = 10^{6} joules |

Mt | megatonne = 10^{6} metric tonnes |

Mtpa | megatonne per year |

Mtoe | million tonne oil equivalent |

MW | megawatt = 10^{6} watt (see watt) |

N | newton, 1 N is the force required to accelerate 1 kg at rate of 1 m/s^{2} |

Nm^{3 } |
normal cubic meter. At 0°C and pressure of 1.013 bar. |

pa | ‘per annum’, per year |

PJ | petajoule = 10^{15} joules |

ppm | parts per million |

t | tonne = 1,000 kilogram |

tpa | ‘tonne per annum’, tonne per year |

TW | terawatt = 10^{12} watt (see watt) |

TWh | terawatt hour = 10^{12} watt hour |

W | watt = 1 J/s. 1 joule per second |