Hydro-Electric Power (HEP) refers to the production of electricity using the force of flowing water. Example of hydroelectric power scheme in Africa can be found in the Zimbabwe/Zambia Border, the Volta project is in Ghana, the Cabora Bassa is in Mozambique, the Owen Falls is in Uganda and the Aswan project is in Egypt.
The following are factors that Influence the Location and Development of Hydro-Electric Power (HEP) Schemes
- Rivers that flow throughout the year – HEP schemes need a constant and large supply of water throughout the year (Perennial River) in order to generate electricity without failure. As a result, a river that flows throughout the year is important for the construction of a dam wall, which will provide a big lake for the supply of water throughout the year. HEP stations, therefore, need to be located on large rivers that flow all year round and where a big dam wall can be constructed to store a lot of water in a reservoir or dam.
- High amounts of rainfall – Since HEP schemes need a lot of water, it means that they are suitable in areas which have high amounts of rainfall throughout the year. The equatorial or tropical climatic regions with average rainfall of over 1500 mm a year are suitable regions for the location of HEP stations. This makes it possible for the river to flow all year round.
- A deep narrow valley with a strong and impermeable rock – Dams constructed for HEP schemes need to be located in a place where a large lake will form without the water flowing away in another direction. As a result, rivers with deep narrow valleys are good sites for the location and construction of dams to be used for HEP schemes. The presence of a strong impermeable rock (hard rock) in the river valley that prevents water from sinking too fast is also considered an important factor for the location of an HEP station.
- Steep and upland gradients – Fast flowing water is needed to generate energy needed for the production of electricity. As a result, steep and upland gradients are important areas where HEP schemes can be located. Steep upland areas make rivers flow very fast providing the necessary force to make the production of electricity very easy.
- Rivers which are free from ice throughout the year and have low sediment load – HEP schemes need to be located on rivers which are free from ice throughout the year. Rivers that have ice for most parts of the year mean that during these periods, water cannot flow, hence making them unsuitable for the production of electricity through HEP schemes. The rivers that are suitable for HEP schemes should also have a low sediment load so that siltation does not occur quickly to reduce the amount of water in a reservoir or dam.