Disadvantages of hydro power plant: i) Due to high cost of civil engineering works, the capital cost per kW of hydro plants is considerably higher than that of steam plants. ii) Hydro power generation is dependent on availability of water. In dry year, the power generation is very small. iii) The firm capacity of hydro plants is low and needs to be backed up by steam plants. iv) Since hydro plants entail huge civil engineering works, they take a considerably long time for completion. v) Hydro plant reservoir submerges huge areas, uproots large population and creates social and other problems.