Solar energy refers to thermal radiation energy from the sun (see the three modes of thermal energy propagation). Its main manifestation is often called solar rays. Nowadays, it is typically used to generate electricity or provide energy for water heaters. Since the birth of life on earth, it has relied primarily on 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 crafting. salt and dry the salted fish. With the decline of fossil fuels, solar energy has become a significant part of human energy consumption and continues to grow. There are two ways to use solar energy: photothermal conversion and photoelectric conversion. Solar power generation is a pennyemerging renewable energy rce. Solar energy in a broad sense also includes wind energy, chemical energy, hydropower, etc. on earth.
Features
Advantages
(1) Universal: The sun shines on the earth, without geographical restrictions, whether on land or sea,
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no matter Mountains or islands are everywhere and can be directly developed and used, easy to collect, and do not require mining or transportation.
(2) Harmless: The development and use of solar energy will not pollute the environment. It is one of the cleanest sources of energy, which is extremely valuable today as environmental pollution becomes more and more serious.
(3) Huge: The energy of solar radiation that reaches the Earth's surface each year is approximately equivalent to 130,000 billion tons of coal, and its total amount constitutese the greatest energy that can be developed in the world today.
(4) Long term: Based on estimates of the rate of nuclear energy produced by the sun, hydrogen storage is sufficient to last tens of billions of years, and the duration life of the Earth is also about billions of years. In this sense, we can say that the energy of the sun is inexhaustible.
Disadvantages
(1) Dispersion: Although the total amount of solar radiation reaching the Earth's surface is large, the density of the energy flux is very low. On average, near the Tropic of Cancer, when the weather is relatively clear in summer, the irradiance of solar radiation is greatest at noon, and the average solar energy received over an area of 1 square meter perpendicular to the direction of light solar is about 1000 W if the day and night average throughout the year is only about 200 W. In winter it is only about thehalf, and on cloudy days it is usually only about 1/5. This energy flow density is very low. Therefore, when using solar energy, if we want to obtain a certain conversion power, we often need a set of collection and conversion equipment with a considerable area, which is expensive.
(2) Instability: due to the limitations of natural conditions such as day and night, season, geographic latitude and altitude, as well as the influence of random factors such as clear , cloudy, cloudy, rain, etc., reaching a certain ground Solar irradiation is both intermittent and extremely unstable, which makes the large-scale application of solar energy more difficult. In order to make solar energy a continuous and stable source of energy and, ultimately, to become an alternative energy source that can compete with conventional energy sources,the problem of energy storage should be well solved, that is, the energy from solar radiation during clear days should be stored as much as possible for use at night or when it rains. It is used for everyday use, but energy storage is also one of the weakest links in solar energy use.
(3) Low efficiency and high cost: solar energyAt the level of utilization development, some aspects are theoretically feasible and technically mature. However, some solar energy utilization devices have low efficiency and high cost, and the current laboratory use efficiency does not exceed 30%. In general, the economy cannot compete with conventional energy. For a considerable period, the future development of the use of solar energy will be limited mainly by economic reasons.
Uses
ToCurrently, solar energy has the following nine main uses in production and life:
1. It mainly collects energy from the sun and heats it to drive the steam turbine to produce electricity;
2. Photovoltaic solar energy production. Combine solar cells of any size;
3. It replaces thermal solar water pumps;
4. Solar Buildings; There are three main forms: the passive building, the active building and the "zero energy building";
6. Used to dry many agricultural and secondary products;
7. It can be divided into two types: hot box type and condensing type;
8. Solar refrigeration and air conditioning. This is an energy-saving, noise-free and pollution-free green air conditioner. 9. Seawater desalination, environmental management and other uses;
Is solar energy a primary energy source ora secondary energy source?
Solar energy refers to the energy of thermal radiation from the sun (see the three modes of thermal energy transmission: radiation). Its main manifestations are: We often say the rays of the sun. Nowadays, it is typically used to generate electricity or provide energy for water heaters.
Since the birth of life on earth, it has mainly relied on the energy of thermal radiation provided by the sun. Since ancient times, humans have also known how to use sunlight to dry objects and use it as a method. to prepare food, such as making salt and drying salted fish. With the decline of fossil fuels, solar energy has become a significant part of human energy consumption and continues to grow. There are two ways to use solar energy: photothermal conversion and converphotoelectric sion. Solar power generation is an emerging renewable energy source. Solar energy in a broad sense also includes wind energy, chemical energy, hydropower, etc. on earth.
The use of solar energy is not yet very popular. There are still problems with using solar energy to generate electricity, such as its high cost and low conversion efficiency. However, solar cells have been used to provide power. artificial satellites.
Humans depend on this energy to survive, including all other forms of renewable energy (except geothermal energy resources), although the total amount of solar energy resources is equivalent to more than 10,000 times the energy used by humans. , solar energy The energy density of solar energy is low and varies from location to location and fromfrom time to time. This is the main problem facing the development and use of solar energy. These characteristics of solar energy will limit its role in the entire integrated energy system.
Solar energy is both a primary energy source and a renewable energy source. It is resource-rich, free to use, requires no transportation, and does not pollute the environment. Created a new way of life for human beings, making societyAnd humanity has entered an era of energy saving and pollution reduction.
The idea of building a space solar power plant was proposed as early as 1968, but only recently have humans started to actually implement it. Japan is one of the pioneers of this project. The project is expected to cost $21 billion and have an electricity production capacity of one billion watts, which can be used by 294,000 homes.s. Building a solar power plant in space can use solar energy to generate electricity regardless of climate, which is different from building a solar power plant on earth.
Primary energy.
Solar energy is a primary energy source. It is a renewable energy source and an essential element for human life.
Solar energy is a renewable energy source, which refers to the energy of thermal radiation from the sun. Its main manifestation is often called solar rays. In modern times, it is generally used to generate or supply electricity. Energy for water heaters. Since the birth of life on earth, we have relied primarily on thermal radiation energy provided by the sun to survive. Since ancient times, humans have also known how to use sunlight to dry objects and use it as mdrying method. preparing food, such as preparing salt and drying salted fish.
As for primary energy, it refers to energy obtained from nature and used directly without modification or transformation, such as raw coal, crude oil, natural gas, hydraulic energy , wind energy, solar energy, ocean energy, tidal energy and geothermal energy. Natural uranium ore, etc.
Disposable energy is divided into renewable energy and non-renewable energy. The first refers to natural energy that can be produced repeatedly, including solar energy, wind energy, tidal energy, geothermal energy, etc. a little less, mainly All types of fossil and nuclear fuels are an indispensable part of life.