1、外文资料翻译 Fossil energy and nuclear energy are considered nonrenewable energy types. Nonrenewable energy is obtained from sources at a rate that exceeds the rate at which the sources are replenished. For example, if the biogenic origin of fossil fuels is correct, we could consider fossil fuels renewabl
2、e over a period of millions of years, but the existing store of fossil fuels is being consumed over a period of centuries. Because we are consuming fossil fuels at a rate that exceeds the rate of replenishment, we consider fossil fuels nonrenewable. Similar comments apply to nuclear fuels such as ur
3、anium, as we observe in later chapters. Solar energy is considered a renewable energy for the following reasons.1 Renewable energy is energy obtained from sources at a rate that is less than or equal to the rate at which the source is replenished. In the case of solar energy, we can use only the amo
4、unt of energy provided by the sun. Because the remaining lifetime of the sun is measured in millions of years, many people consider solar energy an inexhaustible supply of energy. In fact, solar energy from the sun is finite, but should be available for use by many generations of people. Solar energ
5、y is therefore considered renewable. Energy sources that are associated with solar energy, such as wind and biomass, are also considered renewable. Solar radiation may be converted to other forms of energy by several conversion processes. Thermal conversion relies on the absorption of solar energy t
6、o heat a cool surface. Biological conversion of solar energy relies on photosynthesis. Photovoltaic conversion generates electrical power by the generation of an electrical current as a result of a quantum mechanical process. Wind power and ocean energy conversion rely on atmospheric pressure gradie
7、nts and oceanic temperature gradients to generate electrical power. In this chapter we focus on thermal conversion.We first discuss the source of available solar energy, and then consider solar energy technology in two of its three forms: passive solar, and active solar. The third form of solar ener
8、gy, solar electric, is discussed in the next chapter. We end this chapter with a discussion of solar power plants. Fossil fuels in the petroleum and natural gas is the worlds major one-time energy World Energy Council, according to statistics, has proven oil and gas recoverable reserves, according t
9、o the output of countries in 1992 terms, respectively, only the exploitation of 44 years and 60 years； although they may be recoverable reserves there will be new discoveries, but also the growth needs of the community, especially taking into account the economic development of Third World countries
10、, the exploitation of oil and gas fuel for a long time. In fossil fuels, although the most abundant coal reserves, but the serious pollution caused by coal-fired so that it can not become large the major source of energy worldwide. On the other hand, nuclear fusion reactions can provide clean energy
11、, in the ocean contains about 42 trillion tons of the major nuclear fusion of deuterium-reactive substances； fusion reactor but it is very difficult to study, it is estimated that the next century to the late nuclear poly substation be possible to achieve widespread commercialization. Therefore, in
12、the 21st century, the prospects for energy, you may have to face the depletion of oil and gas resources, the commercialization of fusion power failure during the period of temporary shortage of such people. During this period in order to ensure sufficient human clean energy supply, use of solar ener
13、gy for power generation is an inevitable choice. Solar energy is the most important renewable sources of energy, the planet with all kinds of energy are closely related. In fact, the sun in Earths evolution, biological reproduction and human development, plays a very important role, but also provide
14、s a human inexhaustible source of energy. Solar interior ongoing response to the release of a high-temperature nuclear fusion power of about 3. 8 1026 watts of huge radiation, of which only arrived in regard to the atmospheric level 二十亿分之一 ； through the atmosphere, about 30% reflected, 23% be absorb
15、ed, only half (approximately 8 1016 watts) of energy reaching the earths surface. Even so, as long as they can make use of the very few, will be able to meet all the needs of humanity today. However, due to its low energy density, but also by the day and night, seasons, climate, location and other f
16、actors, on the ground by the use of solar energy to power a lot of constraints. In order to avoid these shortcomings, natural to consider the use of solar power in space of the feasibility of the possibility. Power generation in 2010 is expected to the practical use of space Space Solar Power is the
17、 first way of Engineers first proposed by P. Glaser. The basic idea is in the earths outer space or the moon to establish a base of solar power satellites, and then through the microwave energy transmitted to the scene to the receiving device, and then beam microwave energy into electrical energy fo
18、r human use. Advantage of this program is to make full use of solar energy outside the atmosphere, the elimination of solar energy in the ground, changes in the density of small and large shortcomings, without a huge energy storage device, not only to reduce the square, but also save a lot of equipm
19、ent investment. It can be expected, with the photoelectric conversion materials and delivery areas such as technology, space solar power generation costs will be greatly reduced. The idea is proposed, subject to national attention. 1977 -1980 in the United States Department of Energy and NASA organi
20、zations to the concept of space solar power study, believe that its implementation does not exist insurmountable technical difficulties. At that time, a design known as the reference system of power generation systems； from 60 to solar panels, each block 10 kilometers long, five kilometers wide, gen
21、erating 5,000,000 kilowatts, with a total capacity of 300 million kilowatts. With such a power generation satellites, the United States will be able to replace all of the ground station. As the system is too large, about 3,000 of the money to invest 100 billion U.S. dollars, at that time under the c
22、onditions of the Cold War can hardly be supported. With the energy of all the outstanding progress in space technology in 1995, NASA set up a study group to re-examine this issue, a more comprehensive analysis of space solar power generation technical and economic feasibility of the program also are
23、 very different: adopted a progressive self-development model, that is, the first 100-150 to launch a 100 million U.S. dollars investment for 250,000 kilowatts of power satellites, the sale of electricity in order to recover their investment and profit, and then expand the scale of power generation
24、satellites. The research group estimates that after 2010, space power will be practical. At present, a number of other countries and international organizations, space solar power generation is also carried out work. Solar Solar (Solar) generally refers to the suns radiation energy. Carried out in t
25、he solar interior from H together into a helium the nuclear reaction, kept a huge release of energy, and continue to the space radiation energy, which is solar energy. This solar nuclear fusion reaction inside the can to maintain the hundreds of millions of 百亿年first time. Solar radiation to space la
26、unch 3.8x10 23kW power of the radiation, of which 20 billionth of the Earths atmosphere to reach. Solar energy reaching the Earths atmosphere, 30% of the atmosphere reflectance, 23% of atmospheric absorption, and the rest to reach the Earths surface, Its power of 80 trillion kW, that is to say a sec
27、ond exposure to the suns energy on Earth is equivalent to five million tons of coal combustion heat release. The average per square meter in the atmosphere outside the area of energy per minute to receive about 1367w. A broad sense of the solar energy on earth many sources, such as wind energy, chem
28、ical energy, potential energy of water and so on. The narrow sense is limited to solar radiation of solar light thermal, photovoltaic and photochemical conversion of the directly. At this stage, the worlds solar energy is still the focus of the study of solar energy power plant, but the diversificat
29、ion of the use of the condenser, and the introduction of flat-plate collector and a low boiling point working fluid, the device gradually expanded up to maximum output power 73.64kW, Objective To compare the clear and practical, cost remains high. The construction of a typical device are as follows:
30、 1901, California built a solar-powered pumping devices, the use of truncated cone condenser power: 7.36kW； 1902 1908 years, built in the United States five sets of double-cycle solar-powered engines, the use of flat-panel collector and a low boiling point working fluid； in 1913, Human use of solar
31、energy has a long history. China more than 2000 years ago, back in the Warring States period, one will find that the use of four steel mirror to focus sunlight ignition； use of solar energy to dry agricultural products. The development of modern, solar energy has become increasingly widespread use,
32、it includes the use of solar energy solar thermal, solar photovoltaic and solar energy use, such as the photochemical use. The use of solar photochemical reaction, a passive use (photo-thermal conversion) and the photoelectric conversion in two ways.A new solar power and renewable sources of energy use. Silicon photovoltaic cells mainly in the absorption of solar light energy emitted by silicon photocell is mainly extracted from the sand by the development of Bell Labs. Solar energy is the internal or the surface of the sun sunspot continuous process of
