One truck driver that services the fuel depot at the Luton Airport, the scene of the explosions and fire reported earlier today told the BBC, in a story titled Massive explosions hit fuel depot that the depot has twenty tanks each containing 3 million gallons of fuel.
I want you to think about the implication of that information.
Each gallon of petroleum contains approximately 40 Kilowatt-hours of heat energy. Therefore each of the 20 tanks contains approximately 120 Million kilowatt-hours of energy. There are approximately 1162 kilowatt hours of energy in a ton of TNT.
Therefore, each of the 20 fuel tanks contains the equivalent of 103 Kilotons of TNT. That energy equivalent is equal to about 5 times the explosive power of the Hiroshima bomb.
Of course, a tank full of liquid cannot explode all at one time, it will burn as the surface gets exposed to oxygen, the other necessary chemical component of combustion, the comparison with the Hiroshima bomb was simply for perspective on the amount of power potentially stored in fuel depots all around the world.
Residents of the area near the fuel depot are being warned to stay indoors and close their doors against the fumes from the raging fire. There is no word yet on the potential long term damage that breathing the toxic fumes will do to the people that are exposed to the hazard.