Well, one major component is Natural Gas or Coal: http://en.wikipedia.org/wiki/Haber_process http://en.wikipedia.org/wiki/Haber_process > The Haber process no

Well, one major component is Natural Gas or Coal: http://en.wikipedia.org/wiki/Haber_process http://en.wikipedia.org/wiki/Haber_process > The Haber process now produces 100 million tons of nitrogen fertilizer per year, mostly in the form of anhydrous ammonia, ammonium nitrate, and urea. 3-5% of world natural gas production is consumed in the Haber process (~1-2% of the world's annual energy supply). That fertilizer is responsible for sustaining one-third of the Earth's population... This actually doesn't take into account the energy to bring the components to the high temperatures required, either, usually supplied by electricity. The output: http://en.wikipedia.org/wiki/UAN http://en.wikipedia.org/wiki/UAN