A micro-hydroelectric power station. Image credit abc.net.au

ZIMSEC O Level Geography Notes: Natural Resources: Energy: Advantages and Disadvantages of Hydroelectricity


  • Renewable energy source.
  • Cheap to maintain as water-transports itself to plants.
  • Very clean energy source.
  • Easy to use.
  • Very versatile, that is many uses.
  • Large lakes are multi-purpose can also be used for tourism, recreation, sport, irrigation, fishing water supply among others.
  • Urbanization is enhanced as industrial towns grow at or close to HEP stations.
  • Cools and provides moisture to local environment.


  • The world’s best sites are already used only a few good remaining good sites.
  • Expensive to build, for example the James Bay scheme in Canada cost US$50 billion.
  • Large lakes cause crustal instability for example Lake Kariba.
  • Downstream from the lake, aquatic life is destroyed as little water gets there.
  • Silt supply downstream is cut off, affecting agriculture negatively.
  • Siltation’s cuts short the lifespan of an HEP plant.
  • Settlements are destroyed by flooding of lakes as well as roads, rails and other infrastructure, therefore resettlement must occur.
  • Large areas of land suitable of agriculture and settlement are taken up.
  • Water-borne diseases such as bilharzia, malaria and river blindness multiply from the stagnant water.
  • Tension between nations increase due to trapping of water and silt by one country.
  • Cannot power motor vehicles.

To access more topics go to the O Level Geography Notes page