Sit in a darkened room and light a wooden match. Watch it burn. You may not feel the heat. The light it emits may not create more than a glow around your hand. You may or may not smell the slight sulphur tang, and the trail of smoke will surely be tiny. When it burns out, you have consumed a unit of energy called a British Thermal Unit, or a BTU.
Technically, a btu is the amount of energy required to heat a pint of water from 39 to 40 degrees Fahrenheit. But a wooden match burning in a darkened room provides a more concrete image.
Much of the discussion here on Quads will be about how many BTUs per capita people consume in different countries. The U.S. consumed 330 million BTUs per person in 2008, down from a peak of 346 mbtus per capita in 1989, but still an impressive figure.
By contrast, Denmark consumed 152 mbtus per person in 2008, also down from their peak of 186 mbtus in 1996. And China, despite being the largest consumer of energy in the world, spreads that consumption across a larger population–their per capita consumption has grown steadily for decades but only amounted to 65 mbtus per person in 2008.
As you will no doubt tire of reading if you spend much time on this weblog, one of the central questions of this century will be how China develops–if they aim for an American level of energy consumption, they will consume 459 quads per year when they have developed to America’s current levels. If they instead target a Danish lifestyle (which in many ways is materially better than that of America’s), it will be 211.