Hydropower

Hydroelectric power can offer a dependable energy source, replacing fossil fuel plants in areas with sufficient stream flows, like the Pacific Northwest where it supplies 50% of its electricity.

In North America, hydroelectric power generates nearly carbon-free electricity. However, in some locations, it can produce more greenhouse gases than coal power plants.  

Although North America has mostly utilized its prime hydropower sites, Africa possesses substantial untapped potential, presenting an opportunity to significantly increase the continent’s energy. Droughts, however, can dramatically cut power production making hydropower less dependable over longer periods.

Fast Facts

• Hydroelectric power (hydropower) generated with dams provides water storage and reliable power to meet baseline and peak loads given adequate river flows.
• Dams can provide flood control, water storage, and recreational opportunities during their 50, 100-year, or longer lifespan.
• Africa has the largest undeveloped hydropower potential of all continents
• Hydroelectric power can generate greenhouse gas (GHG) levels slightly higher than nuclear, the cleanest energy source, to much more than coal power plants, depending on their vegetation and stream flow patterns.

Background

Hydroelectric power, also called hydropower, is a form of renewable energy that uses the water stored in dams, as well as flowing in rivers, to create electricity in hydropower plants. The falling water rotates the blades of a turbine, which then spins a generator that converts the mechanical energy of the spinning turbine into electrical energy. Hydroelectric power is a significant component of electricity production worldwide.

Dams

Most hydroelectric power is generated with dams that provide water storage, which makes the power particularly useful for meeting baseline and peak demand variation  (unlike unreliable renewable energy, wind, or solar). Hydroelectric power is, however, less reliable than nuclear, gas, and coal generated due to dependence on the hydrological cycle.  The most visible example of this in the US is Hoover Dam located outside Las Vegas, Nevada, which has curtailed and may eventually stop producing power due to a multi-decade drought (and overconsumption).  

Hydropower Distribution

Hydropower plants generate electricity in more than 150 countries, although most of the power is generated in 4 countries, China, Canada, Brazil, and the US..  

While most of the best hydropower dam sites are already in use in North America, Africa has a large undeveloped potential that promises to dramatically increase the continent’s electricity supply.  Unfortunately, the World Bank has been pushing for funding of wind and solar projects instead of reliable hydropower or coal. Leaders of rich countries that have never dealt with unreliable power, due to fossil fuel use to guarantee 24/7 power, hypocritically push unreliable wind and solar power projects on poorer countries.  African leaders, however, are too smart to fall for this scam, having already suffered from incredibly low levels of reliable power.

Environmental Impact

Hydropower dams can flood huge areas of land to create storage reservoirs, eliminating towns,  cities,  and natural areas.  Dams also can destroy fish runs, by preventing their return to spawning. Less well known than the loss of habitat and the effect on fish runs are climate impacts that can exceed the dirtiest coal power plant.

Africa has the world’s highest potential for untapped hydropower, which includes large areas where vegetative growth patterns could increase emissions beyond equivalent fossil fuel electrical plants.