THIS is about a back page report published by a local English daily on September 21 about China's frantic attempt at setting up wind power generation. Compared to generating wind power, producing methane gas from free raw material (human stool) would be a cheaper and much easier option needing ordinary mild steel tanks, pipelines and pumps for production of unlimited volume of methane gas, with perpetual supply of free raw material.
In Bangladesh we should go all out for this source of never ending supply of methane gas, from free plentiful availability of the raw material needed. This is what we should go for rather than setting up tall wing turning generators that need specialised electrical facility storage and conversion facilities for required voltage for use, since generated voltage will be related to the wind speed, that naturally changes randomly depending on the weather.
The first disadvantage of the wind generator will be the large space needed for each installation to enable the generator driving fans to move facing the incoming wind flow direction that can change from time to time. For this each wind generator may need around 30,000 to 40,000 sq. ft of free area, with no trees obstructing and damaging the large wind blades. Also, the generating voltage will vary depending on the wind speed, and the variable speed generator will generate different voltages at different wind speeds that need specialized electrical setup to transform it to the required voltage for distribution.
In contrast, human stool is free. It only needs mild steel tanks for anaerobic decomposition of stool and pumps to blow out the methane gas generated, and standard compressors to store this gas in mild steel tanks at the pressure needed for distribution. Except for pumping the methane gas, all the other work needed can be handled by unskilled rural labour or latrine cleaners of many cities and towns. Also the solid odourless residue, left behind, after methane is extracted can be mixed with used lubricant oils and greases and ash from cooking or coal and wood dust (from furniture makers) mixed together and compressed into fuel cakes that can be used in rural and other 'chulas' and by blacksmiths for heating their materials. We can also use the raw sewage that is often being pumped out from the sewage treatment plant in Dhaka and other towns, liberating germs and other biologically dangerous materials that adversely affect public health about which we are seemingly unaware or ignore it today. Given these realities, we should go all out for recovering methane gas from human stool, rather than treating it and spreading potential diseases into our rivers that rural people use for washing and bathing!
Engr.S.A.Mansoor
Dhaka.
