Hydropower has important environmental benefits, but it can also have negative environmental affects as well.
Advantages of hydroelectric dams:
- Hydropower is renewable.
- Greenhouse gas emissions are very low under normal conditions, particularly in non-tropical regions of the world.
- Dam reservoirs cause large loss of land.
- There is significant damage to ecological systems, both upstream and downstream of the power plant.
- In tropical regions, substantial amounts of methane, a powerful greenhouse gas, can be released, as submerged flora decay under anaerobic conditions.