In theory, water can be used as a source of energy. Water can be broken down into hydrogen and oxygen, both of which are clean, non-polluting fuels. However, with current technology, electrolyzing water to reduce it to hydrogen and oxygen is consuming. a huge amount of energy. The time is too long and the cost is too high, so it cannot be used. Only after the invention of a quick and cheap method of electrolysis of water could water be used as an energy source.
River water can produce electricity, and sea water can also produce electricity.
Use the tides to produce electricity. Tidal power plants and hydroelectric power plants on rivers are based on the same principle. People build a dam in an estuary or bay near the sea and install a hydroelectric generator in the middle of the dam. At high tide, the tideflows from the ocean through the dam to the estuary or bay, driving the turbogenerator to produce electricity; At low tide, when seawater returns to the ocean, it drives the turbine in the opposite direction again. produce electricity. This type of tidal power plant generates more stable energy than hydroelectric plants built on rivers because it is not affected by floods and droughts.
There are three-foot waves on the windless sea. Waves are also a kind of energy, but converting wave energy into electrical energy is much more difficult than generating hydroelectricity. In the 1970s, Japan developed the first wave power generation device. There is also a generator of this type installed on a barge in the United Kingdom.
Using the temperature difference between the surface and deep layers of water mer, electricity can also be generated. This type of power generation device is similar to a thermal power plant: water vapor drives a steam turbine, and the steam turbine drives a generator to produce electricity. The high temperature of the surface seawater serves as a heat source for the steam engine, while the low-temperature deep seawater serves as a cold source to cool the waste steam. The United States has built an experimental seawater temperature difference power plant near Hawaii. Using a temperature difference of 20°C, 50 kilowatts of electricity are generated.