The earth's core is very hot! If we can tap into this renewable source of energy, we will be able to satisfy a large chunk of our energy needs while simultaneously cutting down emissions and pollution dramatically.
I didn't realize that there are three types of geothermal power plants. I have heard that this is a very intensive process, and the site even states that this process is not renewable in the traditional sense of the word. Nonetheless, it seems that this could be a very viable power source for many parts of the world.
This is another idea I have never heard of. It seems that using the geothermal energy stored by mine water to heat and cool buildings could be a viable energy source. However, is it safe? And couldn't it be considered a non-renewable resource?