What are disadvantages of hydroelectric energy?

Question

i also need disadvantages of solar, wind power, geothermal, tidal, biomass, and hydrogen energy

Answer 1

Hydroelectric: Dams on rivers impact aquatic life

Solar: Not cost effective compared to fossil fuels yet, needs sun to function

Wind power: Blades kill birds, needs wind to function

Geothermal: No known drawbacks.  Limited locations of high geothermal heat.

Tidal: Technology still in infancy. Cost effectness not proven yet.

Biomass:  Technology new. Disadvantages unknown

Hydrogen: Need energy to create hydrogen.

Answer 2

Tsk, tsk, tsk....I *think* i know who you are...(if i do) you're using Yahoo Answers for the science debate thing....instead of doing it [research] YOURSELF

OR, if it's not "you"...than oh well.

Oh, and if you use Yahoo Answers, you won't know if the person's info is true...you don't know the bibliography

Answer 3

Living in the Pacific NW, we hear a lot of the salmon go "smack" when they hit the dam wall.

Answer 4

You are basically talking about summarizing several entire branches of research which thus far energy utilities and research bodies have already spent millions of man hours.

So.  Start reading!

Here's a head-start:  Hydroelectric energy is generally based on dams.  Dams seem great, but they actually have huge environmental impact.  Even the most carefully-planned dam will create a lake above it and reduce water flow below it.  Read about what is happening in China with their big dam.

The water coming out of the dam is "thirsty" - depleted of sediment by the dam, now it is extra-erosive.  The river eats away at the river bank, washing soil into the ocean and depleting farmland.

Wind and solar power - still expensive capital investment.

Geothermal - you have to be near a source... like in Iceland

Hydrogen is not an energy source.  Where does the hydrogen come from?  You can't mine it... you have to get it from water.  But that costs more energy than you get from burning it.  So really, we should see hydrogen more like a "battery" than an energy source.  Also note that water is a greenhouse gas.

I can't think of a disadvantage to biomass energy.  Maybe because there is so much mass involved, you'd have to move it all?  Also, if you are generating biomass for the explicit purpose of making energy, you are no longer carbon-neutral.  Also methane is not very good for the envronment.

DO NOT copy and paste what I wrote into a paper.  Each of these things are hints at more research and reading.  Please make sure you understand what I said and why I said it, because that is why I help people.