Hydroelectric

Give two reasons why Hydroelectric power is useful to us:

1. Using water, wind, solar and geothermal resources is better than using resources like coal, oil, and gas because they are renewable, unlike the coal, oil, and gas.
2. Water is provided free by nature so we don't have to go digging everywhere in order to find coal and risk endangering human society or the animal society.

Disadvantages of Hydroelectric power:

Disturbs aquatic life: Hydropower plants are constructed across rivers, and this can interfere with aquatic life. There is a huge chance of aquatic life finding their way into the penstock and eventually into turbines where they will get killed. Building dams in a few certain places can also interfere with mating patterns, seasons and breeding areas of the aquatic animals.

Construction needs large area: In order to build a dam, people have to install power production units, plus transformers, and fasten them onto the main grid requires a big piece of land. People may need to clear out forests or places where people live in order to achieve getting a piece of land. If we were to keep clearing out forests or places where people live then where would the animals go? Where would the humans go? If we put the human houses with the other human houses then it will get crowded. People will use more fossil fuel, and we could get more pollution. 

Hydroelectric dam:

Clyde Dam in Central Otago