by Andrew_S » Sun 02 Dec 2007, 23:18:20
$this->bbcode_second_pass_quote('Pops', 'B')ut wait, if N can be made from air why is it so expensive and the main input cost for corn and most any other crop aside from fuel and seed?
The cost is mainly energy to make N gas react with hydrogen.
$this->bbcode_second_pass_quote('', 'T')he Haber process now produces 100 million tons of nitrogen fertilizer per year, mostly in the form of anhydrous ammonia, ammonium nitrate, and urea. 0.75% of the world's annual energy supply is consumed in the Haber process (3.35% of world natural gas production is used for ammonia production[8][9][1], and natural gas represents 22% of world energy production. [10] See also [11] for rough estimate of 1% of energy production.) That fertilizer is responsible for sustaining one-third of the Earth's population, as well as various deleterious environmental consequences. [12] Generation of hydrogen using electrolysis of water, using renewable energy, is not currently competitive cost-wise with hydrogen from fossil fuels, such as natural gas, and is responsible for only 4% of current hydrogen production. Notably, the rise of this industrial process lead to the "Nitrate Crisis" in Chile, when the British industrials left the country (since the natural nitrate mines were no longer profitable), closing the mines and leaving a large unemployed Chilean population behind.