Our Environment: Part 19 – Hydroelectric Power

This form of renewable energy has been used for decades.  Water at higher elevations flows towards the sea.  Placing a hydroelectric dam on such a waterway the flowing water can turn the turbines and generate electricity.  It is the number one source of renewable energy around the world, and – when including environmental costs – one of the least expensive way to generate electricity.

In 2011 much of the world was looking towards increasing hydroelectric power.  Today it is the number one form of renewable energy around the world and growth is predicted to remain stable through 2030.  One issue of hydropower is droughts generated by climate change.  The are other concerns as well – such as the production of methane from anaerobic decomposition from submerged plants on the bottom of the reservoirs, and the build up of silt within the turbines coming from the rivers flowing through them.

Advantages	Disadvantages
Moderate to high net energy	High construction costs
High efficiency (80%)	High environmental impact from flooding due to the reservoir
Low-cost electricity	High CO2 emissions from rapid biomass decay in shallow tropical reservoirs
Long life span	Danger of collapse
No CO2 emissions during operation in temperate areas	Uproots people
Provides irrigation water	Decreases fish harvest below dam
Reservoir useful for recreation	Decreases need silt below dam

 

References

Projected Costs of Generating Electricity by 2020. International Energy Agency. https://www.iea.org/reports/projected-costs-of-generating-electricity-2020.

Hydroelectricity. International Energy Agency. https://www.iea.org/energy-system/renewables/hydroelectricity.

Miller, G.T., Spoolman, S.E. 2011. Living in the Environment. Brooks/Cole Cengage Learning. Belmont CA. pp. 674.