Clean energy includes tidal energy, wave energy, solar energy, wind energy, hydrogen energy, bioenergy, and geothermal energy.
1. Tidal energy
Tidal energy is the energy contained in the periodic rise and fall of sea water. The water level difference is expressed as potential energy, and the speed of the current is expressed as kinetic energy. Both types of energy can be utilized and are a form of renewable energy. Because tides are the most reliable and regular among the various movements of sea water, and they rise and fall on the shore, they were also the first to be recognized and utilized by people. Among the various uses of ocean energy, the use of tidal energy is the most mature. .
2. Wave energy
Wave energy is a specific form of ocean energy and one of the most important energy sources in ocean energy. Its development and utilization are important for alleviating the energy crisis and It is very important to reduce environmental pollution. The movement of turbulent waves produces huge, eternal and environmentally friendly energy. If the kinetic energy of waves and the wave energy of other water surfaces can be fully utilized, the future of world energy will be quite broad and bright.
3. Solar energy
Solar energy refers to the thermal radiant energy of the sun (see the three ways of heat energy transmission: radiation). Its main manifestation is often referred to as solar rays. . In modern times, it is generally used to generate electricity or provide energy for water heaters.
Since the birth of life on earth, it has mainly relied on the thermal radiation energy provided by the sun. Since ancient times, humans have also known how to use sunlight to dry objects and use it as a method of making food, such as making salt and drying salted fish. wait.
As fossil fuels dwindle, solar energy has become an important part of human energy use and continues to develop. There are two ways to utilize solar energy: photothermal conversion and photoelectric conversion. Solar power generation is an emerging renewable energy source. Solar energy in a broad sense also includes wind energy, chemical energy, water energy, etc. on the earth.
IV. Wind energy
Wind energy is mainly used in two forms: wind energy as power and wind power generation, of which wind power generation is the main one. Using wind energy as power means using wind to directly drive various mechanical devices, such as driving water pumps to lift water. The advantages of wind engines are: low investment, high efficiency, economy and durability.
5. Hydrogen energy
Hydrogen energy is the energy released by hydrogen during physical and chemical changes. Hydrogen energy is the chemical energy of hydrogen. Hydrogen mainly appears in the form of chemical compounds on the earth. It is the most widely distributed substance in the universe. It constitutes 75% of the mass of the universe and is a secondary energy source. There are many ways to produce hydrogen industrially.
Common ones include water electrolysis to produce hydrogen, coal gasification to produce hydrogen, heavy oil and natural gas steam catalytic conversion to produce hydrogen, etc. However, the energy consumed by these reactions is greater than the energy produced.
Baidu Encyclopedia—Clean Energy