Air pollution solution calculations : Many people do not realise that there is a sufficient amount of solar energy to heat massive volumes of air every day. The problem is getting air to come into intimate contact with hot surfaces. The ground heats air immediately above it, but there is not intimate contact with large volumes of air. Solar air heaters provide large hot surface areas and intimate contact. See http://www.builditsolar.com/Experimental/PopCanVsScreen/PopCanVsScreen.htm
Often about 7 kWh of solar energy fall on every square metre of surface in a day. This is 7x3600 kJ, which is 25200 kJ of energy. Air has a volumetric heat capacity of about 1.2 kJ/(deg C.cubic metre) and we might ask how many cubic metres of air we could heat by 5 deg C every day with the 25200 kJ? The answer is we can heat 25200/(5x1.2) cubic metres by 5 deg C in a day. We divided by 1.2 (volumetric heat capacity) and by 5 (the number of degrees the air is heated.). This is 4200 cubic metres that can be heated 5 deg C in a day by a 1 square metre solar air heater.This has great implications for diluting air pollution, for enhancing chances of convectional rain and for cooling cities. If we place a large number of solar air heaters above each other on a tall pole we could have massive heating of air.
2) Decide on the area of your solar air heater and multiply (eg 100 sq metres and 6 kWh per sq metre per day. kWh=6x100=600 kWh. This is 600x3600 kJ (1 kWh=3600 kJ) ie this is 2160000kJ).
3) If you heat the air 5 deg C, then number of cubic metres heated in a day by 5 deg C = 2160000/(5xvolumetric heat capacity). You can get the volumetric heat capacity from the chart.
4) If the system is only 70% efficient, then multiply by 70/100=0.7.