2 Responses to “explain why energy sources such as wind power,geothermal,tidal and solar power contribute to our energy needs?”

1. Richard B says:

   October 27, 2011 at 8:11 am

   all sources of energy contribute to our energy needs.

   the most plentiful and cheapest forms are fossile fuels like oil and coal. They produce carbon dioxide gas when burned and too much of that in the air can change the climate.
   That is what the argument about “Global Warming” is about.
2. Ron R says:

   October 27, 2011 at 9:05 am

   Your answer is as follows:

   Wind power is gaining popularity and market share, but it requires the wind to blow within a predictable speed range.

   Geothermal is currently expensive to produce. Some parts of the world are involved in “Hot Rocks” technology, but it requires deep bore holes to be drilled, and that type of drilling is expensive.

   Harnessing tidal energy is still (largely) in the development stage.

   Solar power is viewed as only supplemental power due to the fact that (as it is currently done) it cannot generate power twenty-four hours a day.

   None of these technologies produce much (if any) greenhouse gas emissions.