| There are essentially four types of alternate energies | | | | convert it to electrical energy. Of course a dam is not |
| that we are currently focusing on. They are solar, wind, | | | | always a necessity when you are thinking of producing |
| hydroelectric and geothermal. Massive amounts of | | | | electricity to light a city or a densely populated area. |
| research and development are taking place in the | | | | Today there are smaller run-of-river hydroelectric |
| developed nations of the world towards getting | | | | energy converters which produce adequate electricity |
| self-reliant in terns of energy requirements for the | | | | to light homes as well as offices. |
| future. This article discusses briefly about two such | | | | - One of the most under-appreciated and untapped |
| types, hydroelectric and geothermal energies: | | | | sources of alternate energy is geothermal energy, |
| - Over and above the sun and the wind, water too | | | | which lay dormant as heat energy under the surface |
| yields immense of power which can be harnessed to | | | | of the earth. This heat forms steam which then comes |
| generate electricity to light and heat our homes. Today | | | | out of vents on the surface of the earth. Geothermal |
| we know how to harness its force, in response to | | | | energy plants draw out this hot steam, called 'dry |
| gravity, meaning the force of water as it flows downhill | | | | steam'. The plants are also called 'flash' power plants |
| and put them in turbines which then produce electricity. | | | | or 'binary' power plants. The reason why the hot |
| Though forceful water is not difficult to find, producing | | | | water from below the surface of the earth is drawn |
| hydroelectric energy is both expensive and | | | | up is to gather the steam power. On of the best |
| complicated. We can only control water energy if we | | | | known geothermal sites is The Geysers, located 100 |
| construct dams, which again is an expensive | | | | miles north of San Francisco, which is an ideal example |
| proposition. We need to store as well as control the | | | | of a dry steam plant. |
| kinetic energy produced by flowing water and then | | | | |