Renewable energy sources
Sunday, 13 June 2010
In his article titled 'Efficient utilisation of renewable energy resources', published in the June 6, 2010 issue of the Financial Express, Mr. Shahiduzzaman Khan has made the issue unnecessarily complex. Why should we need research on the already established matter of using biogas as a fuel for generating power by power plants? This could be done by steam power plants or gas turbines. What is needed is wide publicity and government encouragement and support, in the form of financing on easier terms and tax rebates for imported components.
The writer has wrongly described "natural gas" as biogas which is not the correct technical nomenclature. Natural gas is extracted from geological sources, very much like coal and oil, by digging gas wells. Both natural gas and biogas have methane as the combustible substance in the gas phase at normal temperature and pressure.
Biomass is treated in digesters and its biological decomposition produces methane. This can be used for cooking or as a fuel in thermal power plants for generating electric power from steam or gas turbines or from internal combustion gas engines.
Among the sources of biomass which can produce methane, the writer has not mentioned the most readily available and common refuse that can generate methane -- human 'solid excreta'. This large potential fuel source is totally wasted in Bangladesh.
Thailand, which has no fuel source and imports practically all fuel, has already set up many biogas plants from "human solid refuse" in large public accommodations like armed forces and police barracks.
The methane gas produced is used for cooking and the residue is periodically recovered and the odourless mass is compressed and sold as fertilizer.
For Bangladesh, aside from photo voltaic power already established, we can also harness wind power from residential wind turbines installed in high-rises and multi-storied public buildings. We should also go for generating methane and producing fertilizer from human solid waste.
Regarding hydro-power, apart from recovering power from the potential energy of "head of water" (Kaptai Dam), we should go for utilising water current in our rivers to generate electric power from "water-wheel generators". These can be mounted on fixed moored barges, or on river banks, and we can get electricity from this source also. However, as far as we know, we do not have high tidal surges to generate tidal power which is done in some coastal areas in Europe. May be, our government should set up a small river current-driven power plant for demonstration and as an encouragement for private sector investment on it, as they have done for wind power in Cox's Bazar.
Engr. S.A. Mansoor
Dhaka.
The writer has wrongly described "natural gas" as biogas which is not the correct technical nomenclature. Natural gas is extracted from geological sources, very much like coal and oil, by digging gas wells. Both natural gas and biogas have methane as the combustible substance in the gas phase at normal temperature and pressure.
Biomass is treated in digesters and its biological decomposition produces methane. This can be used for cooking or as a fuel in thermal power plants for generating electric power from steam or gas turbines or from internal combustion gas engines.
Among the sources of biomass which can produce methane, the writer has not mentioned the most readily available and common refuse that can generate methane -- human 'solid excreta'. This large potential fuel source is totally wasted in Bangladesh.
Thailand, which has no fuel source and imports practically all fuel, has already set up many biogas plants from "human solid refuse" in large public accommodations like armed forces and police barracks.
The methane gas produced is used for cooking and the residue is periodically recovered and the odourless mass is compressed and sold as fertilizer.
For Bangladesh, aside from photo voltaic power already established, we can also harness wind power from residential wind turbines installed in high-rises and multi-storied public buildings. We should also go for generating methane and producing fertilizer from human solid waste.
Regarding hydro-power, apart from recovering power from the potential energy of "head of water" (Kaptai Dam), we should go for utilising water current in our rivers to generate electric power from "water-wheel generators". These can be mounted on fixed moored barges, or on river banks, and we can get electricity from this source also. However, as far as we know, we do not have high tidal surges to generate tidal power which is done in some coastal areas in Europe. May be, our government should set up a small river current-driven power plant for demonstration and as an encouragement for private sector investment on it, as they have done for wind power in Cox's Bazar.
Engr. S.A. Mansoor
Dhaka.