Advantages and Disadvantages of Hydroelectric power - Facts

What is hydroelectric power (facts) ? 

Let’s start with the hydroelectric power definition:

In hydroelectric power plants, the potential energy of water is converted into mechanical energy which runs a generator.

  • Hydraulic power is a naturally available renewable energy source. 
  • Power of a hydroelectric power station is given as: P = gρQH watts 
  • Where g = 9.81 m/s2, p = 1000 kg/m3, Q is the flow or discharge in m3/s, and H is the height of fall of water or head in m. 
  • The efficiency of the turbine-generator assembly in a hydroelectric power plant usually varies between 50% and 90%.
  • Almost 20% of the total power requirement of the world comes from hydro power

  • Countries like Norway and Switzerland are almost totally dependent on hydropower.

Advantages and disadvantages of hydroelectric power

Advantages of Hydro power plants : 

Hydro power has a number of advantages:

  • Water source is always available – no extra fuel is needed to be used to produce electricity
  • The running costs of hydro power installations are very low.
  •  Hydro power is environmentally benign.

  •  The operation of Hydraulic turbine can be started or stopped in very short time.

  • The hydraulic power plant is comparatively simple in concept and design.
  • The operation of hydroelectric power plant is self-reliant.
  • Hydro power stations are much more reliable in comparison with other power plants. 

  • Modern hydro power equipment has a life of nearly 50 years.  With extraordinary maintenance the life can be increased to more than 50 years. 

  • Hydroelectric plant can handle the load very easily and thus they can be used as the ideal spinning reserve in an electrical system. 

  • Modern hydro-generators give high efficiency as well as handle a considerable range of load which helps improving the overall system efficiency. 

  •  Manpower requirement is low; also the manpower need not be highly skilled
  • The extra or bonus advantages of hydroelectric power are - they provide the means of irrigation and also contributes in flood control etc.
hydroelectric power

Disadvantages of Hydro power plants

The disadvantages are:

  • Cost of hydroelectric power is a matter of great concern. Hydropower projects are capital intensive with a low rate of return

  • Annual cost of hydropower installations takes a big part of the annual interest of the capital.
  • The growth period of hydroelectric power projects s quite large

  • The foundation and completion of a hydro power project is very hefty.  Ten to fifteen years may be needed to complete the project.

  • Power generation is totally dependent on the quantity of water available, which may vary from season to season and year to year.

  • These plants are often far away from the load center (most of the time in remote areas) and require long power transmission lines to deliver power — thus the cost of transmission lines are very high as well as losses in them are very significant.  


  1. Nice post! Thanks for the post, I will look forward to see more posts from your blog. Tube Sheet



Copyright © Mechanical Engineering Design by Free CSS Templates | Blogger Theme by BTDesigner | Powered by Blogger