Energy from the sea:
- Tidal energy:
- Tidal energy is the natural renewable source of energy which is due to the rise and fall of water level in the sea.
- As we know that gravitation force exist between every objects. Earth provides necessary centripetal force for circular revolution of moon around the earth it produces rise and fall of water level in sea.
- Tidal energy is the pure source of energy which does not produces any type of pollution and it has great future as source of energy.
- There are so many tides occurred in sea during a day. This tides has greater energy. We can also utilise this energy for generation of electricity.
- The tidal energy is used for converting it into the electrical energy for many purposes.
- Tidal energy is the pure and clean renewable source of energy than other renewable energy sources because it does not affect to marine life and environment.
- Wave energy:
- Wave energy is produced due the waves gkoenerated on the surface of ocean because of the wind action on the surface of water.
- This is also a renewable source of energy which is converted into electric energy and used for many purposes, water desalination also.
- The wave energy is produced only at the sea surfaces where wind blowing action is strong.
- Wave energy is also the sustainable renewable source of energy which has no disadvantages other than their location.
- Ocean thermal energy:
- Due to the high temperature of sunlight the upper surface of sea water gets heated while the layers below remains cold.
- As we know that temperature difference creates heat energy similar to night difference creates gravitational potential energy.
- The difference in temperature of this layers is used to generate ocean thermal energy.
- The plants are developed if this temperature difference corresponds upto 20k at a distance of 2km.
- This temperature difference is used to vaporise the liquid or fluid having low boiling point like ammonia.
- After vaporisation of that liquid, the vapours are used to expand and to rotate the turbines by which energy electrical energy is generated.
- Ocean thermal energy is also a renewable source of energy but in some extent it affects the environment.
Geothermal energy:
- Big Bang theory explains the origin of universe. Earth is also a part of sun like other planets.The temperature of earth was about 6000 degreecelsius same as core of sun. Rain fell on earths surface from millions of years so outer layer of Earth cool down but interior does not. This inner core has temperature about 4000 to 4500 degree Celsius. All solid materials are melt due to such high temperature in a core. At this temperature some nuclear reaction takes place like core of the Sun.
- As we go towards earth’s crust the temperature is increasing more and more and due to this geological changes occurs.
- This geological changes leads to formation in molten rocks in deeper part of earth’s crust they get trapped at some surfaces which are known as hot spots.
- This hotspots sometimes come in contact with underground hot water forms steam. In some reasons this hot water comes out from the earth’s surface which are known as hot springs.
- The steam generated is used in producing electrical energy for various purposes.
- Geothermal energy is not completely pollution free source of energy because in mining lot of poisonous gases are evolved which are very harmful.
Answer the following questions
- State advantages of geothermal energy.