Clean energy is a kind of energy which does not produce pollutants in the use procedure. It includes nuclear energy and 'renewable energy'. Renewable energy refers to a kind of inexhaustible energy such as hydropower, wind power, solar energy, biomass energy (biogas), water energy, and tidal energy and so on.
Renewable energy doesn’t have the possibility of energy depletion, and that’s why scientists and especially countries short of energy pay attention to it. Traditionally, clean energy refers to a kind of energy that is friendly to the environment, whose features include fewer emissions, environmental protection, and little pollution, etc. But this concept is not accurate enough. People are likely to consider that it is the classification of energy. Forming of such a concept that energy includes clean energy and dirty energy makes people misunderstand the clean energy itself.
Solar energy refers to solar radiation energy from the sun. Since the formation of the earth, organisms have long been living on the light and heat provided by the sun. But the application of solar energy is widely concerned only till recent decades. As the oil resource is increasingly consumed, more people begin to turn their eyes to the solar energy for its inexhaustible characteristics. Most of the useful energy comes from the sun both directly and indirectly. Early in human history, variety of plants stored solar energy into the plants themselves with photosynthesis by converting solar energy into chemical energy. The formation of coal, oil, natural gas and other fossil fuels has taken a long time with the wreckages of all kinds of animals and plants underground. It is the energy indirectly coming from the sun.
Wind energy is a kind of kinetic energy which comes from the air flow on the surface of the earth. Because air temperature and water vapor content will change after irradiation by the sun, causing different pressure in different places. The air flows to the low pressure area from the high pressure area in horizontal direction, so formed the wind. Wind energy resource depends on the availability of wind energy density and the cumulative number of hours. It is estimated that the total wind energy all over the world is about 130,000,000,000 kW (kilowatt). Wind energy resources is mainly affected by the terrain, the wind energy resources are more concentrated in the coastal and open continent or the contraction zone of our earth. Natural wind is a kind of energy that is renewable, nonpolluting and inexhaustible. With the advent of global warming and energy crisis, many countries are stepping up the investment to develop wind energy, so as to reduce the emission of carbon dioxide and other greenhouse gas to protect our environment. There are two methods to make use of the wind energy. The first is to take wind as the direct power. The second is to produce electricity indirectly with wind. The major advantages of wind engines are of less investment, highly efficient and economical.
Ocean energy refers to the energy kind that is the attachment of the sea, through a variety of physical processes for receiving, storing and distributing energy. The energy is stored in the tides, waves, temperature, salinity gradient, currents and other forms in the sea. The accurate definition of clean energy is that the clean energy is the technology system which is clean, efficiently, and systematization for using. It has three important points. Firstly, clean energy is not a kind of energy but a technology system. Secondly, clean energy not only emphasizes cleanness but also economy. Thirdly, the features of clean energy refer to certain standards.
Water energy is another renewable energy which is the pressure energy and kinetic energy of water. Water resources generally include river water, tidal energy, wave energy, ocean energy and other flowing water resources. But in a narrow sense, water energy only refers to the river water resources that could be drunk by people. Water not only can be used by man, it is the energy carrier. The water on the earth runs circularly with the solar energy. The surface water is very important and the resource is rich in hydropower resources. With the dwindling of fossil fuels, water is a kind of energy that is very important and promising energy resources. Rivers, tidal, wave and swell and other water sports can be used for power generation. The heating value of hydrogen fuel is as four times as the equivalent weight of carbon, fuel product is water, no pollution to the environment, is the ideal clean energy in the future.
In general, the development of clean energy is still at the primary stage, we still have a long way to go.
Written by Greenshine New Energy, solar street lights manufacturer. More info here