Cahc 2009

A 1,000 square meter Urban Farming roof top green house can potentially produce 43,000 kilos of tomatoes a year. Since tomatoes are 95% percent water and 4% carbohydrate composition, this results in 1,720 kilos of carbohydrates. The general formula of carbohydrates is Cn(H2O)n or empirical values of CH2O. With Carbon at 12 Atomic units, Hydrogen at 2 atomic units and Oxygen at 16 atomic units for a total 30 atomic units molecular weight. The carbon component is therefore 12/30 or 40%. Thus, of the 1,720 kilos of carbohydrates, carbon is 688 kilos.

All this carbon is taken carbon dioxide in the urban air. Since the chemical formula of carbon dioxide is CO2, the molecular weight is 12 + (16 *2) or 44. Thus, the amount of carbon dioxide removed from the air is (688 kilos / 12) *44 or 2,523 kilograms, 2.5 Tons per year all from just a single building. This is value 2.523 kilograms per square meter and applying this to a 800,000 square meter roof top area of a 1 square kilometer urban area, this totals 2,018,133 kilograms or 2,018 tons of CO2 per year.