Compare and contrast bio-mass and hydro-electricity as source of energy. The production cost of hydro-electricity is cheaper than the electricity produced in a thermal power station. Explain why?
| Biomass | Hydroelectricity |
|---|---|
| Energy supplied by the burning of biomass causes pollution. | It does not cause any pollution. |
| Energy can be obtained by burning it directly or by a gobar gas plant. | Hydroelectricity can be obtained by constructing dams. |
In a thermal power station, coal is burnt to produce electricity whereas, hydroelectricity is produced by allowing the water to fall on turbines. Water in rivers is available free of cost but the cost of extracting and transporting coal is very high.