能源相关外文翻译

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能源专业外文翻译--来自太阳的能源

外文原文：ENERGY FROM THE SUNThe sun has produced energy for billions of years. Solar energy is the solar radiation that reaches the earth. Solar energy can be converted directly or indirectly into other forms of energy, such as heat and electricity. The major drawbacks (problems, or issues to overcome) of solar energy are: (1) the intermittent and variable manner in which it arrives at the earth's surface and, (2) the large area required to collect it at a useful rate. Solar energy is used for heating water for domestic use, space heating of buildings, drying agricultural products, and generating electrical energy.In the 1830s, the British astronomer John Herschel used a solar collector box to cook food during an expedition to Africa. Now, people are trying to use the sun's energy for lots of things.Electric utilities are trying photovoltaics, a process by which solar energy is converted directly to electricity. Electricity can be produced directly from solar energy using photovoltaic devices or indirectly from steam generators using solar thermal collectors to heat a working fluid. Out of the 14 known solar electric generating units operating in the US at the end of 2004, 10 of these are in California, and 4 in Arizona. No statistics are being collected on solar plants that produce less than 1 megawatt of electricity, so there may be smaller solar plants in a number of other states. PHOTOVOLTAIC ENERGYPhotovoltaic energy is the conversion of sunlight into electricity through a photovoltaic (PVs) cell, commonly called a solar cell. A photovoltaic cell is a nonmechanical device usually made from silicon alloys.Sunlight is composed of photons, or particles of solar energy. These photons contain various amounts of energy corresponding to the different wavelengths of the solar spectrum. When photons strike a photovoltaic cell, they may be reflected, pass right through, or be absorbed. Only the absorbed photons provide energy to generate electricity. When enough sunlight (energy) is absorbed by the material (a semiconductor), electrons are dislodged from the material's atoms. Special treatment of the material surface during manufacturing makes the front surface of the cell more receptive to free electrons, so the electrons naturally migrate to the surface.When the electrons leave their position, holes are formed. When many electrons, each carrying a negative charge, travel toward the front surface of the cell, the resulting imbalance of charge between the cell's front and back surfaces creates a voltage potential like the negative and positive terminals of a battery. When the two surfaces are connected through an external load, electricity flows.The photovoltaic cell is the basic building block of a PV system. Individual cells can vary in size from about 1 cm (1/2 inch) to about 10 cm (4 inches) across. However, one cell only produces 1 or 2 watts, which isn't enough power for most applications. To increase power output, cells are electrically connected into a packaged weather-tight module. Modules can be further connected to form an array. The term array refers to the entire generating plant, whether it is made up of one or several thousand modules. As many modules as needed can be connected to form the array size (power output) needed.The performance of a photovoltaic array is dependent upon sunlight. Climate conditions (e.g., clouds, fog) have a significant effect on the amount of solar energy received by a PV array and, in turn, its performance. Most current technology photovoltaic modules are about 10 percent efficient in converting sunlight with further research being conducted to raise this efficiency to 20 percent.The pv cell was discovered in 1954 by Bell Telephone researchers examining the sensitivity of a properly prepared silicon wafer to sunlight. Beginning in the late 1950s, pvs were used to power U.S. space satellites. The success of PVs in space generated commercial applications for pv technology. The simplest photovoltaic systems power many of the small calculators and wrist watches used everyday. More complicated systems provide electricity to pump water, power communications equipment, and even provide electricity to our homes.Photovoltaic conversion is useful for several reasons. Conversion from sunlight to electricity is direct, so that bulky mechanical generator systems are unnecessary. The modular characteristic of photovoltaic energy allows arrays to be installed quickly and in any size required or allowed.Also, the environmental impact of a photovoltaic system is minimal, requiring no water for system cooling and generating no by-products. Photovoltaic cells, like batteries, generate direct current (DC) which is generally used for small loads (electronic equipment). When DC from photovoltaic cells is used for commercial applications or sold to electric utilities using the electric grid, it must be converted to alternating current (AC) using inverters, solid state devices that convert DC power to AC. Historically, pvs have been used at remote sites to provide electricity. However, a market for distributed generation from PVs may be developing with the unbundling of transmission and distribution costs due to electric deregulation. The siting of numerous small-scale generators in electric distribution feeders could improve the economics and reliability of the distribution system.SOLAR THERMAL HEATThe major applications of solar thermal energy at present are heating swimming pools, heating water for domestic use, and space heating of buildings. For these purposes, the general practice is to use flat-plate solar-energy collectors with a fixed orientation (position).Where space heating is the main consideration, the highest efficiency with a fixed flat-plate collector is obtained if it faces approximately south and slopes at an angle to the horizon equal to the latitude plus about 15 degrees. Solar collectors fall into two general categories: nonconcentrating and concentrating.In the nonconcentrating type, the collector area (i.e. the area that intercepts the solar radiation) is the same as the absorber area (i.e., the area absorbing the radiation).In concentrating collectors, the area intercepting the solar radiation is greater, sometimes hundreds of times greater, than the absorber area. Where temperatures below about 200o F are sufficient, such as for space heating, flat-plate collectors of the nonconcentrating type are generally used.There are many flat-plate collector designs but generally all consist of (1) a flat-plate absorber, which intercepts and absorbs the solar energy, (2) a transparent cover(s) that allows solar energy to pass through but reduces heat loss from the absorber, (3) a heat-transport fluid (air or water) flowing through tubes to remove heat from the absorber, and (4) a heat insulating backing.Solar space heating systems can be classified as passive or active. In passive heating systems, the air is circulated past a solar heat surface(s) and through the building by convection (i.e. less dense warm air tends to rise while more dense cooler air moves downward) without the use of mechanical equipment. In active heating systems, fans and pumps are used to circulate the air or the heat absorbing fluid.SOLAR THERMAL POWER PLANTSSolar thermal power plants use the sun's rays to heat a fluid, from which heat transfer systems may be used to produce steam. The steam, in turn, is converted into mechanical energy in a turbine and into electricity from a conventional generator coupled to the turbine. Solar thermal power generation is essentially the same as conventional technologies except that in conventional technologies the energy source is from the stored energy in fossil fuels released by combustion. Solar thermal technologies use concentrator systems due to the high temperatures needed for the working fluid.PARABOLIC TROUGHThe parabolic trough is used in the largest solar power facility in the world located in the Mojave Desert at Kramer Junction, California. This facility has operated since the 1980 and accounted for the majority of solar electricity produced by the electric power sector in 2004.A parabolic trough collector has a linear parabolic-shaped reflector that focuses the sun's radiation on a linear receiver located at the focus of the parabola. The collector tracks the sun along one axis from east to west during the day to ensure that the sun is continuously focused on the receiver. Because of its parabolic shape, a trough can focus the sun at 30 to 100 times its normal intensity (concentration ratio) on a receiver pipe located along the focal line of the trough, achieving operating temperatures over 400 degrees Celcius.A collector field consists of a large field of single-axis tracking parabolic trough collectors. The solar field is modular in nature and is composed of many parallel rows of solar collectors aligned on a north-south horizontal axis. A working (heat transfer) fluid is heated as it circulates through the receivers and returns to a series of heat exchangers at a central location where the fluid is used to generate high-pressure superheated steam. The steam is then fed to a conventional steam turbine/generator to produce electricity. After the working fluid passes through the heat exchangers, the cooled fluid is recirculated through the solar field. The plant is usually designed to operate at full rated power using solar energy alone, given sufficient solar energy. However, all plants are hybrid solar/fossil plants that have a fossil-fired capability that can be used to supplement the solar output during periods of low solar energy. The Luz plant is a natural gas hybrid.SOLAR DISHA solar dish/engine system utilizes concentrating solar collectors that track the sun on two axes, concentrating the energy at the focal point of the dish because it is always pointed at the sun. The solar dish's concentration ratio is much higher that the solar trough, typically over 2,000, with a working fluid temperature over 750o C. The power-generating equipment used with a solar dish can be mounted at the focal point of the dish, making it well suited for remote operations or, as with the solar trough, the energy may be collected from a number of installations and converted to electricity at a central point. The engine in a solar dish/engine system converts heat to mechanical power by compressing the working fluid when it is cold, heating the compressed working fluid, and then expanding the fluid through a turbine or with a piston to produce work. The engine is coupled to an electric generator to convert the mechanical power to electric power.SOLAR POWER TOWERA solar power tower or central receiver generates electricity from sunlight by focusing concentrated solar energy on a tower-mounted heat exchanger (receiver). This system uses hundreds to thousands of flat sun-tracking mirrors called heliostats to reflect and concentrate the sun's energy onto a central receiver tower. The energy can be concentrated as much as 1,500times that of the energy coming in from the sun. Energy losses from thermal-energy transport are minimized as solar energy is being directly transferred by reflection from the heliostats to a single receiver, rather than being moved through a transfer medium to one central location, as with parabolic troughs. Power towers must be large to be economical. This is a promising technology for large-scale grid-connected power plants. Though power towers are in the early stages of development compared with parabolic trough technology, a number of test facilities have been constructed around the world.Last Revised: July 2008Sources: Energy Information Administration, Electric Power Annual,Form EIA-860, Annual Electric Generator Report database.中文译文：来自太阳的能源太阳产生能量已有数十亿年，太阳能是太阳辐射到地球的能量。

新能源经济【外文翻译】

（2011届）本科毕业设计（论文）外文翻译原文：THE NEW ENERGY ECONOMYEveryone agrees it's time, but the obstacles go well beyond matters of technology. Why real change will take nothing less than a new American revolutionTo describe what's needed to wean the country off fossil fuels, people often use the word transition. But transition is too smooth. It suggests steadiness, even inevitability, as if the endpoint is predetermined.The outcome of the tremendous push that's now underway to change how the United States and other countries obtain and consume energy is anything but predetermined. There are no definite answers to questions about the role one source of energy or another will play 15 or 20 years from now, no clear sense about the type of fuel (if any) people will put in their cars, no consensus on how quickly any of this can happen or at what cost.Nor is the change likely to be smooth and quiet. Instead, it will probably be disruptive, breaking down existing ways of thinking and acting. Not that disruption is bad: Joseph Schumpeter, the famous Austro-Hungarian economist, once spoke of "creative destruction," whereby new technologies and ideas replace old ones, which themselves are overthrown by newer, more progressive ones.Already, 2009 has been a year of visions, of prophecies. President Barack Obama's inaugural address offered one such vision: doubling alternative energy production in the next three years, updating and expanding the nation's energy infrastructure, saving billions of dollars in energy costs through improved energy efficiency. Think tanks, businesses, industry groups, and environmentalists have laid out their own plans, some more aggressive and some less so.The sheer number of these plans, not to mention the interest percolating up from nearly all corners of American life, suggests, as Energy Secretary Steven Chu puts it, that "the landscape is changing."Clean energy is, of course, a narrative that has been slowly developing in the UnitedStates over the past four decades or so, at least since President Jimmy Carter's administration. In the past, its visibility and its urgency have ebbed and flowed with the price of oil. Today, however, it's not just the wild fluctuation in oil prices that is driving the discussion. There is the economic crisis. There is the burgeoning climate crisis, with its implicit call for global cooperation. And there are fresh concerns about national security in an age of emboldened oil cartels and nuclear ambitions. Addressing each of these priorities raises its own set of questions. At the moment, there is no consensus on how aggressively the United States should reduce greenhouse gas emissions over the few next decades or, more broadly still, the proper role of fossil fuels and renewable energy.Meanw hile, almost every potential contributor to a “green energy economy"--wind and solar power, befouls, nuclear power, energy efficiency--faces hurdles well beyond the technology of each system. Regulatory policies or economic issues stand in the way of massive, quick deployment of any of these.And so, today, a new mentality is emerging among almost all the major energy players, from wind developers in the Dakotas to coal-plant operators in North Carolina: Energy issues can no longer be treated as piecemeal policy items left up to states and hodgepodge federal legislation to decide but instead must be addressed nationally, in a sweeping manner.Want the country running on flex-fuel vehicles? "It's just a few hundred dollars more per vehicles," says retired Gen. Wesley Clark, the 2004 presidential candidate and now cochairman of Growth Energy, a group representing several of the nation's largest ethanol producers. "What would encourage an automobile manufacturer to believe he should do it would be a government policy that says we are moving in that direction."Want more wind power? "The critical thing we are talking about here is national policy and the signals it sends to people," says Denise Bode, CEO of the American Wind Energy Association. "There is tremendous demand for wind power, but there is not enough transmission."The idea that a nation should have a clear-cut national energy policy sounds obvious enough. In the United States, however, the truth is that energy has not always beenconsidered a national issue, and in some ways it still isn't.Nowhere is this more obvious than with the transmission grid, a sprawling jumble of wires and mechanical connections dating back 50, 80, even 100 years in some places. Today, the grid is divided into more than 140 "balancing areas" to help manage the distribution of power. But some are so localized that they can't communicate with their next-door neighbors. As a result, extra power in one region is often wasted rather than being sent to a place that needs it.So if wind power, solar power, and plug-in electric vehicles are to be big players in the country's energy future, as many hope, this antiquated system for delivering electricity will have to change. The grid must be retooled, and new high-capacity power lines are needed to carry wind-generated electricity from the Midwest to the East and West coasts. To get those high-power lines approved, Bode and other advocates say, the federal government needs more authority to override nasty squabbles between states, environmentalists, and other interest groups that have typically stalled such efforts. The federal government, the thinking goes, already has the authority to build natural gas pipelines across state lines, and electricity should be no different. That sentiment seems to be gaining ground even among regulators who once opposed it, although there are many issues still to be worked out. As Chu says, "If we just take the view that we are going to cram something down someone's throat, this is not a constructive way of doing business" (interview, Page 32). Infrastructure is only one part of the battle to make national energy problems a national issue. Another is technology. Even though wind power technology is relatively mature--it was the country's largest provider of clean electricity last year--most other renewable sources still need work. Improvements to photovoltaic cells could reduce solar power costs significantly. New drilling technologies could help geothermal spread across a larger geographic range. Advancements in befouls, in particular to the enzymes needed to break down grasses and woods to produce ethanol, would have a major impact. Meanwhile, fossil fuels face their own technological challenges. If coal is to stay around for a while, it'll most likely be because of still-developing methods to capture carbon dioxide emissions before they enter the atmosphere.Scientific breakthroughs don't come cheap. The economic stimulus package set aside $21.5 billion for scientific research, signaling that Washington is taking a much more active role in basic energy issues after years of declining budgets at national labs. But this is just the groundwork. The most powerful force to remake the energy America uses could be government policies: climate change legislation, which would set a price on carbon dioxide emissions, and a national renewable-electricity standard, which would require the United States to get a certain portion of its electricity from renewable energy. Both rules could have far-reaching impacts, forcing industries to massively reconsider their operations, giving financial investor’s confidence to pump money into wind farms, solar fields, and other industries, and convincing the coal industry that it's worth investing billions in technology to reduce emissions.The consequences of climate change legislation, in fact, are expected to be so great that companies typically opposed to government regulation are asking Congress to go ahead and act just so that they can have some certainty about where to put their money.What Washington won't do--not in theory, anyway--is pick specific winners. "The market will decide what the mix will be," says Matt Rogers, a former director at McKinsey & Co. and now one of Chu's top advisers. "It will be interesting to see what the market brings forward." Of course, in reality, Congress's record is one of subsidizing some industries but not others. Even within the befoul world, corn-based ethanol is heavily supported, but some others, such as befoul made from algae, receive almost no backing.In this new era of national energy, one of the primary questions facing the country is that of timing. When should things happen? And how soon can they occur? "Broadly, what scares me is that we want to do this in an incremental fashion. We want this to come across as painlessly as possible," say Rich Wells, vice president of energy at Dow Chemical. "We need a breakthrough mentality."It has become a cliché to say that there is no "silver bullet" for the nation's energy and climate problems. Most experts prefer to think about energy solutions as a collection of options to be deployed in tandem. Perhaps the most widely quoted example is the "wedge model," developed by Princeton University professors Stephen Pocola andRobert Soochow in 2004. It outlined 15 wedges, each one representing a way to significantly reduce greenhouse gas emissions over the next 50 years. Among them: raising the fuel economy of 2 billion cars from 30 mpg to 60 mpg and doubling nuclear capacity worldwide.Only some of these, of course, are realistic in the shorter term. "If you're only going to do one, the top one is always energy efficiency," says Dow's Wells. "It is for the most part the easiest, cheapest fuel out there." Amory Loins, chief scientist at the nonprofit Rocky Mountain Institute, agrees, saying that energy savings from highly fuel-efficient cars would be equivalent to "finding a Saudi Arabia under Detroit." Perhaps the biggest barrier for buildings has been the upfront cost of doing retrofits, with the need to convince people that the costs can be quickly recouped by lower energy bills. The stimulus package is taking a stab at this, setting aside $5 billion for home weatherization.Meanwhile, everyone else is jockeying for position. The befoul industry wants Congress to lift the cap on how much ethanol can be blended into gasoline. The nuclear industry is asking Congress to cough up billions to insure new nuclear power plants; wind and solar industries are asking for transmission superhighways. Detroit wants more in government bailout money. And coal wants money to research carbon capture technology. The great energy nationalization is here.译文：新能源经济每个国家都希望开发新能晕，但局限于开发的障碍以及技术问题。

热能与动力工程专业外文翻译、中英对照、英汉互译

毕业设计外文翻译原文标题：Proposal for a high efficiency LNGpower-generation System utilizing wasteheat from the combined cycle中文标题:一个高效的利用液化天然气联合循环余热的发电系统学院名称：能源与动力工程学院专业名称：热能与动力工程Proposal for a high efficiency LNG power-generation system utilizing waste heat from the combined cycleY. Hisazumi*, Y. Yamasaki, S. SugiyamaEngineering Department, Osaka Gas Co., 1-2 Hiranomachi 4-chome Chuo-ku, Osaka 541, Japan Accepted 9 September 1998AbstractHigh-efficiency power-generation with an LNG vaporizing system isproposed: it utilizesthe LNG's cold energy to the best potential limit. This system can be applied to LNG vaporizers in gas companies or electric power companies and recovers the LNG's cold energy as electric power. The system consists of a Rankine cycle using a Freon mixture, natural-gas. Rankine cycle and a combined cycle with gas and steam turbines. The heat sources for this system are the latent heat from the steam-turbine's condenser and the sensible heat of exhaust gas from the waste-heat recovery boiler. In order to find out the optimal condition of the system, several factors, such as gas turbine combustion pressure, steam pressure, condensing temperature in combined cycle, composition of mixture Freon, and natural gas vaporizing pressure are evaluated by simulation. The results of these studies show that in the total system, about 400 kWh can be generated by vaporizing 1 ton of LNG, including about 60 kWh/LNG ton recovered from the LNG cold energy when supplying NG in 3.6 MPa.. About 8.2MWh can be produced by using 1 ton of LNG as fuel, compared with about 7 MWh by the conventional combined system. A net efficiency of over 53%HHV could be achieved by the proposed system. In the case of the LNG terminal receiving 5 million tons of LNG per year, this system can generate 240 MW and reduce the power of the sea water pump by more than 2MW. 1998 Elsevier Science Ltd. All rights reserved.1. IntroductionIn the fiscal year 1994, the amount of LNG imported to Japan reached about 43 million tons; of this 31 million tons were used as fuel for power generation. As shown in Fig. 1, about 20% of the LNG imported was used for power generation [2]. Fig. 2 shows the major LNG power generation systems now in operation and their outputs. Several commercial LNG power generation plants have been constructed since 1979, and their total output has reached approximately 73 MW. Among the new power-generation plants without CO2 emission, this value of 73 MW is second to the 450 MW input of geo-thermal power generation plants in Japan, with the exception of power generation by refuse incinerators, and is much larger compared with the 35 MW output of solar-power plants and the 14 MW output of wind-power stations.Table 1 shows the LNG power generation plants constructed in Japan. The economics of LNG power generation became worse as the appreciation of the yen madethe cost of energy kept constant but while raising the construction cost; the adoption of the combined cycle utilizing gas-turbine and steam turbine (hereafter called combined cycle) increased the gas send-out pressure and lowered the power output per ton of LNG. Therefore, no LNG powergeneration plants were constructed in the 1990s due to lower cost effectiveness of the systems.As for the thermal power plant using natural gas as fuel, the steam turbine produced only about 6 MWh of power output per ton of LNG. But recently, improvement in blade-cooling technology and materials of the gas turbine enabled a 1400℃class turbine to be designed and increased the combustion pressure up to 3 MPa. Therefore, as shown in Fig. 3, the heat efficiency of the combined cycle has been improved and the electrical output from 1 ton of LNG has reached about 7MWh.In this paper, a proposal is made for the high-efficiency LNG power generation system based on a new concept which fully utilizes the cold energy without discarding it into the sea. The system is composed of the combined cycle and the LNG power-generation plant.2. High-efficiency LNG power-generation system2.1. Basic componentsFig.4 shows the process flow diagram of the high-efficiency LNG power-generation system. This complex system consists of the combined cycle and the LNG power generation cycle. The combined cycle is composed of a gas turbine (GAS-T) and a steam turbine (ST-T) using natural gas (NG) as fuel, while the LNG power generation cycle is composed of a Freon (uorocarbon) mixture turbine (FR-T) and a natural-gas turbine (NG-HT, NG-LT) using the latent heat of condensation from the exhaust steam and the sensible heat of the exhaust gas as heat sources. The plate fin type heat exchanger can be used for the LNG/natural gas (LNG-CON) and LNG/ Freon mixture (FR-CON). The shell-and-tube type can be selected as exchangers for exhaust steam/natural gas (LNG-VAP),exhaust steam/Freon mixture(FR-VAP), and exhaust gas/natural gas (NG-SH) applications according to the operating conditions.Ice thickness on the surface of the heat-exchanger tubes becomes a problem as heat is exchanged between exhaust gas and cold natural gas or Freon mixture. The ice thickness can be estimated by the technology of heat transfer between LNG and sea water, thus enabling one to avoid blockages due to ice inside the tubes.In addition, stable and continuous send-out of gas is made possible by using a bypass system, even if turbines and pumps for the Freon mixture and natural gas circulating systems (FR-RP, LNG-RP) stop.2.2. Features of the systemThe practical use of the following existing technologies in combination shows the high feasibility of the proposed system:. Power generation using Freon or hydrocarbon type Rankine cycle,. Power generation by natural-gas direct expansion],. TRI-EX type vaporizer which vaporizes LNG by using an intermediate medium or vacuum type LNG vaporizer.The Freon mixture is made up of the HFC type, which is a fluorocarbon consisting of H, F, and C and has no adverse influence on the ozone layer; it enables reduction in exergy loss at the heat exchanger and increases itscirculating flow rate to be achieved.The effective recovery of cold exergy and pressure exergy is made possible by the combined system using natural gas and Freon mixture Rankine cycle.Fig. 5 shows the temperature-heat duty relation when vaporizing 1 kg of LNG in the system shown in Fig. 4. Separation of the condensed natural-gas in two sections enables an increase in the heat duty between Freon (FR) and LNG, and a reduction of difference in temperature of LNG and natural gas between the inlet and outlet of the heat exchanger.3. Evaluation of the characteristics of the proposed system3.1. Process simulationThe characteristics of this system were evaluated by using process simulator. The followings are the conditions used for the calculation:Effciencies of rotating machines LNG compositionGas turbine (GAS-T) 88% CH4 89.39%Steam turbine (ST-T) 85% C2H6 8.65%Natural-gas turbine (NG-HT, LT) 88% C3H8 1.55%Freon turbine (FR-T) 88% iC4H10 0.20%Air compressor (AIR-C) 85% nC4H10 0.15%LNG pump (LNG-MP, RP) 70% iC5H12 0.01%Freon pump (FR-RP) 70% N2 0.05%Natural gas gross heat-value: 10,510 kcal/Nm3AIR/NG flow ratio of gas turbine: 323.2. Effects of send-out pressure of the natural gasWhen natural-gas is sent out at 3.5 or 1.8 MPa, evaluations were made of the effects of send-out pressure of the LNG and change in superheating temperature of the natural gas on the total output of the high pressure (NG-HT) and the low pressure (NG-LT) natural-gas expansion-turbines. Fig. 6 shows the results of this calculation, where self consumption of power is calculated from the power, raising the pressure of the LNG up to the inlet pressure of the turbine minus the power required for the original send-out pressure. In both cases, the inlet pressure rise for the turbine causes an increase of self consumption power, but brings about a greater out-put. About 7 MPa of the inlet pressure of the turbine is appropriate considering the pressure tolerance of the heat exchangers.When the superheating temperature of the natural gas at the inlet to the turbine becomes high, the recovery of power increases, but the temperature of the exhaust gas from the outlet of the natural-gas super heater (NG-SH) declines, thus indicating that there is a limitation to superheating gas.3.3. Effects of combustion pressure of the gas turbineThe outputs of the gas turbine and the steam turbine, and the efficiency per gross heating value were evaluated by changing the combustion pressure of the gas turbine operating at 1300℃turbine-inlet temperature - see Fig. 7.If the combustion pressure of the gas turbine becomes high, the output of the gas turbine increases, but the output of the steam turbine decreases because the rise in combustion pressure causes a lowering of the exhaust-gas temperature at the outlet of the gas turbine and consequently a decline in the steam temperature at the inlet of the steam turbine. However, the overall efficiency of the turbines increases upon increasing the combustion pressure because the increment of gas-turbine output exceeds the decrement of steam turbine output. As a result, taking the pressure loss into account, it is appropriate to set the send-out pressure of the natural gas at the LNG terminal at 3.5 MPa.（FR-vap），3.4. Effects of Inlet pressure of the steam turbineFig. 8 shows the relations between the steam-turbines output and exhaust gas temperatures by changing the steam pressure in the range of 3-7 MPa. As the steam pressure increases, the output of the steam turbine rises and the temperature of the exhaust gases also increase. Besides, the power required for the water-supply pump increases with a rise in the steam pressure. Therefore, the current combined cycles operate at steam pressure of 7 MPa or more because the increment of the output of steam turbine exceeds the additional power required for the water-supply pump.3.5. Rankine cycle using a Freon-mixture refrigerant.The Freon refrigerant was selected from the HFC refrigerants on the basis of marketability, boiling point and freezing-point. Table 2 shows the physical properties of HFC Freon.When only HFC-23 is used as the medium, because of its low freezing-point it never freezes even if heat is exchanged between the LNG and HFC-23. But if HFC-23 is heated by the exhaust steam of the steam turbine, the pressure rises approximately up to the critical pressure. Therefore, the use of HFC-23 is not cost effective, because it is then necessary to set a high design pressure. To cope with this problem, we evaluated the compound refrigerant composed of HFC-134a (with high boiling point) and HFC-23.Fig. 9 shows saturated vapor pressure at various temperatures, the boiling point and the dew point at atmospheric pressure for mixtures of HFC-23 andHFC-134a of various compositions. The saturated pressure at each temperature rises with the increasing mole ratio of HFC-23: Hence, 40-45% of the mole ratio of HFC-23 is the optimal value considering the design pressure of the equipment.Fig. 10 shows the plots of the output of the Freon turbine versus the condensing temperature of the steam turbine when changing the composition of the HFC-23. In this figure, the turbine outlet pressure is determined in such a way that thedifference in temperature between the LNG and Freon mixture is not less than 5℃in the Freon condenser (FR-CON). The Freon turbine's inlet-pressure is set to the saturatedtemperature of the Freon mixture, i.e. less than 2℃from the steam-condensing temperature.This figure indicates that the output of the turbine scarcely correlates with the mole ratio of HFC-23. The higher the steam-condensing temperature becomes, the greater the output per ton of LNG the turbine produces, but in such a case, it is necessary to evaluate the system as a whole because more fuel is required, as described below. The result indicates that the optimal mole composition of HFC-23 and HFC-134a is 40%/60% considering both design pressure and the output of the turbine.3.6. Comprehensive evaluation from the viewpoint of the steam-condensing Temperature.As the dew point of the exhaust gas is 42℃, it is wise to set the exit temperature of the exhaust gas from the natural-gas super heater (NG-SH) to 80℃or more in order to prevent white smoke from the smoke stack. Table 3 shows the effect of the steam-condensing temperature on the generated output of the total system. The lower steam-condensing temperature brings about a higher efficiency of the total system, but also causes a lowering in the inlet temperature of natural-gas turbine. Therefore, it is appropriate to set the steam-condensing temperature at approximately 30℃.When the condensing temperature is 30C, the generated outputs per ton of LNG of the combined cycle and LNG power generation plant are 342.83 and67.55 kWh, respectively, resulting in 402.64 kWh of total generated output aftersubtracting the self-use power. As 48.94 kg of fuel is used for operating the system, the generated outputs of the combined cycle and the total system reach about 7 and 8.2 MWh, per ton of fuel respectively.3.7. Evaluation of exergyNatural-gas is liquefied at an LNG liquefaction terminal, with the consumption of about 380 kWh/LNG-ton: 1 ton of LNG having about 250 kWh of physical exergy as cold exergy and 13.5 MWh of chemical exergy. Fig. 11 shows the result of evaluating the exergy of the system shown in Fig. 4 under the optimal condition. The total output of Freon and natural gas turbines is 67.5 kWh, and the effective recovery percentage of cold exergy is 56%. As 90 kWh out of the pressure exergy can be recovered as output, about 157 kWh of net recovery can be obtained, which indicates the recovery percentage reaches about 63% for 250 kWh of LNG cold exergy. This conversion efficiency is higher than that achieved from chemical exergy to electric power.Most of the exergy loss occurs in the heat exchanger and the turbine, and in mixing with re-condensed LNG. As for the turbines, the loss of energy may be improved by using high-efficiency turbines. On the other hand, modification of the heat exchanger to reduce the energy loss may cause increased complexity of the system and is difficult to be done from the economic viewpoint. Though the recovery.percentage of cold energy in this system is low compared with the 80% in air-separation equipment, this system has the advantage of recovering a large amount of the available cold energy.4. ConclusionThe paper has proposed a high-efficiency LNG power generation system in combination with a combined-cycle power generation system fueled by natural-gas. The system utilizes LNG cold energy and it requires no sea water as a heat source.This system can be applied to LNG vaporization and send-out processes of gas companies or electric-power companies. The system recovers LNG coldenergy as an electric-power output without wasting it into sea water. The system consists of Rankine cycle with Freon mixture and a natural-gas Rankine cycle using the latent heat of exhaust steam from the steam turbine and the sensible heat of exhaust gas from the waste-heat recovery boiler. To improve the total efficiency of the system, a simulation was conducted to evaluate several factors, such as the composition of the Freon mixture, natural gas send-out pressure, as well as the combustion pressure steam inlet pressure, and steam-condensing temperature of the combined cycle. As a result, not less than 60 kWh/LNG-ton of output was generated even at a high natural-gas send-out pressure of 3.5 MPa. This value is considerably higher than the output generated at a LNG send-out pressure of 3 or 4 MPa, as given in Table 2.The system can produce about 400 kWh of net output when vaporizing 1 ton of LNG. While the conventional combined-cycle system in operation generates about 7 MWh when 1 ton of LNG is used as fuel, the system using the same amount of fuel generates about 8.2 MWh with a high degree of efficiency: a not-less-than 53% conversion efficiency was achieved per gross heat value.In the case of an LNG terminal receiving 5 million tons of LNG per year, this system can generate a power of about 240 MW when 600 t of LNG is used in an hour. With the elimination of about 24,000 tons per hour of sea water, which has been used for vaporizing 600 t/h of LNG in the conventional system, no less than 2 MW of electric power for operating sea water pumps can be saved.The proposed system emits no CO2, and can generate a large amount of electricity with high cost efficiency when incorporated into a combined cycle, with no use of sea water. Therefore, we consider that installation of this system is the one of the most favorable means of investment to put a new energy source or energy-saving equipment to practical use.To realize the full potential of this system, it is necessary to understand the heat characteristics of the Freon mixture, the icing and heat transfer characteristics of exhaust steam, the controllability of total system and the characteristics against partial load.References[1] The Center for Promotion of Natural gas Foundation. Research and development report of cold energy utilizing system, 1994[2] Japan's Energy and Economy Research Center. Energy and economy statistical data in 1995[3] Abe. Operating results and future prospect of a recent combined-cycle power generation plant. Thermal and Nuclear Power 1995;46(6):33-41[4] Maertens J. Design of Rankine cycles for power generation. Int. Refrig. 1986;9:137-43[5] Terada, Nakamoto. Power generation utilizing LNG cold. Thermal and Nuclear Power Generation 1986;37(10):66-71[6] Ooka, Ueda, Akasaka. Advanced LNG vaporizer and power generation utilizing LNG cold. Chemical Engineering 1981;45(3):187-90[7] Miura. The development of LNG vaporizer using vacuum steam heat (VSV). Journal of Japan Gas Society 1992;45:34-6[8] Nagai. Software-package and the usage. Chemical Equipment1994;August:31-7[9] Daikin Co. Ltd. Freon Data Sheet of HFC23一个高效的利用液化天然气联合循环余热的发电系统日本大阪541燃气有限公司工程部1-2平野町4肖梅中央谷，1998年9月概述本文提出了一个高效液化天然气气化发电系统，它是利用液化天然气冷能的最佳潜能极限。

能源类外文文献翻译（译文1）

太阳能蒸馏：一种有前途的供水代替技术，它使用免费的能源，技术简单，清洁Hassan E.S.Fath埃及，亚历山大，亚历山大大学机械学院工程系摘要：太阳能蒸馏为盐水淡化提供了一种替代技术，它使用免费的能源、技术简单、清洁，为人类提供所需的部分淡水。

太阳能蒸馏系统的发展已经证明：当天气情况良好，并且需求不太大时，比如少于200立方米／天，它在海水淡化过程中有一定的适用性。

太阳能蒸馏器的产量低这个问题迫使科学家研究许多提高蒸馏器产量和热效率，以此来降低产水的费用。

本文对许多最新发展的单效和多效太阳能蒸馏器进行了整体评论和技术评估。

同时，对蒸馏器构造的发展、各部件在运行过程中出现的问题、对环境的影响也进行了阐述。

关键词：太阳能;海水淡化1.简介在淡水需求超出了淡水资源所能满足的量的地方，对低质量的水进行去盐处理是一种合适的淡水来源途径。

对盐水或海水脱盐处理取得淡水满足了社会基本的需求。

一般说来，它不会对环境造成严重的损害作用。

因此，进行海水淡化的工序和工厂在数量上和能力上都有了巨大的进步。

许多不同的海水淡化技术被用来从盐水中分离淡水，包括有：多级闪蒸（MSF）、多效（ME）、蒸汽压缩(VC)、反渗透（RO）、离子交换、电渗析、相变和溶剂萃取。

但是，这些技术只能产生少量的淡水，因而是昂贵的。

另一方面，用来驱动这些技术的传统能源也会对环境产生消极的作用。

而太阳能蒸馏为盐水淡化技术提供了一种有前途的替代处理过程，它使用免费的能源，技术简单，清洁，并能为人类提供所需的部分淡水。

太阳能蒸馏系统的发展已经证明：当天气情况良好，并且需求不太大时，比如少于200立方米／天，它在海水淡化过程中有一定的适用性。

太阳能蒸馏器的产量和热效率，以此来最小化产水费用。

这些方法中包括被动的和主动的单效蒸馏器。

一些工作者也曾试图都产生的水蒸气在外部凝结（在额外的凝结表面上）。

另一方面，浪费的凝结潜热也被利用，从而增加馏出水的产量和提高效率。

能源专业外文翻译--燃料电池及其发展前景1

外文原文：Fuel Cells and Their ProspectsA fuel cell is an electrochemical conversion device. It produces electricity fromfuel (on the anode side) and an oxidant (on the cathode side), which react in the presence of an electrolyte. The reactants flow into the cell, and the reaction products flow out of it, while the electrolyte remains within it. Fuel cells can operate virtually continuously as long as the necessary flows are maintained.Fuel cells are different from electrochemical cell batteries in that they consume reactant from an external source, which must be replenished--a thermodynamically open system. By contrast batteries store electrical energy chemically and hence represent a thermodynamically closed system.Many combinations of fuel and oxidant are possible. A hydrogen cell uses hydrogen as fuel and oxygen (usually from air) as oxidant. Other fuels include hydrocarbons and alcohols. Other oxidants include chlorine and chlorine dioxide.Fuel cell designA fuel cell works by catalysis, separating the component electrons and protonsof the reactant fuel, and forcing the electrons to travel though a circuit, hence converting them to electrical power. The catalyst typically comprises a platinum group metal or alloy. Another catalytic process takes the electrons back in, combining them with the protons and oxidant to form waste products (typically simple compounds like water and carbon dioxide).A typical fuel cell produces a voltage from 0.6 V to 0.7 V at full rated load.Voltage decreases as current increases, due to several factors:•Activation loss•Ohmic loss (voltage drop due to resistance of the cell components and interconnects)•Mass transport loss (depletion of reactants at catalyst sites under high loads, causing rapid loss of voltage)To deliver the desired amount of energy, the fuel cells can be combined in series and parallel circuits, where series yield higher voltage, and parallel allows a stronger current to be drawn. Such a design is called a fuel cell stack. Further, the cell surface area can be increased, to allow stronger current from each cell.Proton exchange fuel cellsIn the archetypal hydrogen–oxygen proton exchange membrane fuel cell (PEMFC) design, a proton-conducting polymer membrane, (the electrolyte), separates the anode and cathode sides. This was called a "solid polymer electrolyte fuel cell" (SPEFC) in the early 1970s, before the proton exchange mechanism was well-understood. (Notice that "polymer electrolyte membrane" and "proton exchange mechanism" result in the same acronym.)On the anode side, hydrogen diffuses to the anode catalyst where it later dissociates into protons and electrons. These protons often react with oxidants causing them to become what is commonly referred to as multi-facilitated proton membranes (MFPM). The protons are conducted through the membrane to the cathode, but the electrons are forced to travel in an external circuit (supplying power) because the membrane is electrically insulating. On the cathode catalyst, oxygen molecules react with the electrons (which have traveled through the external circuit) and protons to form water — in this example, the only waste product, either liquid or vapor.In addition to this pure hydrogen type, there are hydrocarbon fuels for fuel cells, including diesel, methanol (see: direct-methanol fuel cells and indirect methanol fuel cells) and chemical hydrides. The waste products with these types of fuel are carbon dioxide and water.The materials used in fuel cells differ by type. In a typical membrane electrode assembly (MEA), the electrode–bipolar plates are usually made of metal, nickel or carbon nanotubes, and are coated with a catalyst (like platinum, nano iron powders or palladium) for higher efficiency. Carbon paper separates them from the electrolyte. The electrolyte could be ceramic or a membrane.Oxygen ion exchange fuel cellsIn a solid oxide fuel cell design, the anode and cathode are separated by an electrolyte that is conductive to oxygen ions but non-conductive to electrons. The electrolyte is typically made from zirconia doped with yttria.On the cathode side, oxygen catalytically reacts with a supply of electrons to become oxygen ions, which diffuse through the electrolyte to the anode side. On the anode side, the oxygen ions react with hydrogen to form water and free electrons. A load connected externally between the anode and cathode completes the electrical circuit.Fuel cell design issuesCostsIn 2002, typical cells had a catalyst content of US$1000 per-kilowatt of electric power output. In 2008 UTC Power has 400kw Fuel cells for $1,000,000 per 400kW installed costs. The goal is to reduce the cost in order to compete with current market technologies including gasoline internal combustion engines. Many companies are working on techniques to reduce cost in a variety of ways including reducing the amount of platinum needed in each individual cell. Ballard Power Systems have experiments with a catalyst enhanced with carbon silk which allows a 30% reduction (1 mg/cm2 to 0.7 mg/cm2) in platinum usage without reduction in performance.The production costs of the PEM (proton exchange membrane). The Nafion membrane currently costs €400/m². In 2005 Ballard Power Systems announced that its fuel cells will use Solupor, a porous polyethylene film patented by DSM.Water and air management (in PEMFC). In this type of fuel cell, the membrane must be hydrated, requiring water to be evaporated at precisely the same rate that it is produced. If water is evaporated too quickly, the membrane dries, resistance across it increases, and eventually it will crack, creating a gas "short circuit" where hydrogen and oxygen combine directly, generating heat that will damage the fuel cell. If the water is evaporated too slowly, the electrodes will flood, preventing the reactants from reaching the catalyst and stopping the reaction. Methods to manage water in cells are being developed like electroosmotic pumps focusing on flow control. Just as in a combustion engine, a steady ratio between the reactant and oxygen is necessary to keep the fuel cell operating efficiently.Temperature managementThe same temperature must be maintained throughout the cell in order to prevent destruction of the cell through thermal loading. This is particularly challenging as the 2H2 + O2 =2H2O reaction is highly exothermic, so a large quantity of heat is generated within the fuel cell.Durability, service life, and special requirements for some type of cells Stationary fuel cell applications typically require more than 40,000 hours of reliable operation at a temperature of -35°C to40°C, while automotive fuel cells require a 5,000 hour lifespan (the equivalent of 150,000 miles) under extreme temperatures. Automotive engines must also be able to start reliably at -30 °C and have a high power to volume ratio (typically 2.5 kW per liter).HistoryThe principle of the fuel cell was discovered by German scientist Christian Friedrich Schönbein in 1838 and published in one of the scientific magazines of thetime. Based on this work, the first fuel cell was demonstrated by Welsh scientist Sir William Robert Grove in the February 1839 edition of the Philosophical Magazine and Journal of Science, and later sketched, in 1842, in the same journal. The fuel cell he made used similar materials to today's phosphoric-acid fuel cell.In 1955, W. Thomas Grubb, a chemist working for the General Electric Company (GE), further modified the original fuel cell design by using a sulphonated polystyrene ion-exchange membrane as the electrolyte. Three years later another GE chemist, Leonard Niedrach, devised a way of depositing platinum onto the membrane, which served as catalyst for the necessary hydrogen oxidation and oxygen reduction reactions. This became known as the“Grubb-Niedrach fuel cell”. GE went on to develop this technology with NASA and McDonnell Aircraft, leading to its use during Project Gemini. This was the first commercial use of a fuel cell. It wasn't until 1959 that British engineer Francis Thomas Bacon successfully developed a 5 kW stationary fuel cell. In 1959, a team led by Harry Ihrig built a 15 kW fuel cell tractor for Allis-Chalmers which was demonstrated across the US at state fairs. This system used potassium hydroxide as the electrolyte and compressed hydrogen and oxygen as the reactants. Later in 1959, Bacon and his colleagues demonstrated a practical five-kilowatt unit capable of powering a welding machine. In the 1960s, Pratt and Whitney licensed Bacon's U.S. patents for use in the U.S. space program to supply electricity and drinking water (hydrogen and oxygen being readily available from the spacecraft tanks).United Technologies Corporation's UTC Power subsidiary was the first company to manufacture and commercialize a large, stationary fuel cell system for use as a co-generation power plant in hospitals, universities and large office buildings. UTC Power continues to market this fuel cell as the PureCell 200, a 200 kW system (although soon to be replaced by a 400 kW version, expected for sale in late 2009). UTC Power continues to be the sole supplier of fuel cells to NASA for use in space vehicles, having supplied the Apollo missions, and currently the Space Shuttle program, and is developing fuel cells for automobiles, buses, and cell phone towers; the company has demonstrated the first fuel cell capable of starting under freezing conditions with its proton exchange membrane automotive fuel cell.Fuel cell efficiencyThe efficiency of a fuel cell is dependent on the amount of power drawn from it. Drawing more power means drawing more current, which increases the losses in the fuel cell. As a general rule, the more power (current) drawn, the lower the efficiency.Most losses manifest themselves as a voltage drop in the cell, so the efficiency of a cell is almost proportional to its voltage. For this reason, it is common to show graphs of voltage versus current (so-called polarization curves) for fuel cells. A typical cell running at 0.7 V has an efficiency of about 50%, meaning that 50% of the energy content of the hydrogen is converted into electrical energy; the remaining 50% will be converted into heat. (Depending on the fuel cell system design, some fuel might leave the system unreacted, constituting an additional loss.)For a hydrogen cell operating at standard conditions with no reactant leaks, the efficiency is equal to the cell voltage divided by 1.48 V, based on the enthalpy, or heating value, of the reaction. For the same cell, the second law efficiency is equal to cell voltage divided by 1.23 V. (This voltage varies with fuel used, and quality and temperature of the cell.) The difference between these numbers represents the difference between the reaction's enthalpy and Gibbs free energy. This difference always appears as heat, along with any losses in electrical conversion efficiency.Fuel cells do not operate on a thermal cycle. As such, they are not constrained, as combustion engines are, in the same way by thermodynamic limits, such as Carnot cycle efficiency. At times this is misrepresented by saying that fuel cells are exempt from the laws of thermodynamics, because most people think of thermodynamics in terms of combustion processes (enthalpy of formation). The laws of thermodynamics also hold for chemical processes (Gibbs free energy) like fuel cells, but the maximum theoretical efficiency is higher (83% efficient at 298K) than the Otto cycle thermal efficiency (60% for compression ratio of 10 and specific heat ratio of 1.4). Comparing limits imposed by thermodynamics is not a good predictor of practically achievable efficiencies. Also, if propulsion is the goal, electrical output of the fuel cell has to still be converted into mechanical power with the corresponding inefficiency. In reference to the exemption claim, the correct claim is that the "limitations imposed by the second law of thermodynamics on the operation of fuel cells are much less severe than the limitations imposed on conventional energy conversion systems". Consequently, they can have very high efficiencies in converting chemical energy to electrical energy, especially when they are operated at low power density, and using pure hydrogen and oxygen as reactants.In practice, for a fuel cell operating on air (rather than bottled oxygen), losses due to the air supply system must also be taken into account. This refers to the pressurization of the air and dehumidifying it. This reduces the efficiency significantlyand brings it near to that of a compression ignition engine. Furthermore fuel cell efficiency decreases as load increases.The tank-to-wheel efficiency of a fuel cell vehicle is about 45% at low loads and shows average values of about 36% when a driving cycle like the NEDC (New European Driving Cycle) is used as test procedure. The comparable NEDC value for a Diesel vehicle is 22%. In 2008 Honda released a car with fuel stack claiming a 60% tank-to-wheel efficiency.Fuel cells cannot store energy like a battery, but in some applications, such as stand-alone power plants based on discontinuous sources such as solar or wind power, they are combined with electrolyzers and storage systems to form an energy storage system. The overall efficiency (electricity to hydrogen and back to electricity) of such plants (known as round-trip efficiency) is between 30 and 50%, depending on conditions. While a much cheaper lead-acid battery might return about 90%, the electrolyzer/fuel cell system can store indefinite quantities of hydrogen, and is therefore better suited for long-term storage.中文译文：燃料电池及其发展前景燃料电池是一种电化学转换装置。

生物质能源外文翻译外文文献英文文献中国的生物质能源

China’s Biomass EnergyChina leads the world in its energy reservation and is the second largest energy producer and consumer in the world. It is estimated that China has 4000 billion tons of potential primary energy reservation. However, per capita energy resource quantity and consuming quantity is far smaller than the world average level. The main characteristics of China’s energy exploration and utilization are as follows.1. Coal is the primary energy; exploration and utilization of renewable resources is supplementary. China’s explored reserves of coal resource accounts for over 90% of the primary energy total, such as coal, oil, natural gas, water energy and nuclear energy. Coal is dominant id China’s energy production and consumption.on.2. Energy consumption volume is increasing while energy utilization efficiency is comparatively low. As the economic scale expands, China’s energy consumption is on the constant increase. Under the influences of capital, technology, energy price, etc, China’s energy utilization efficiency is far lower than that of the developed countries. Energy comprehensive utilization efficiency is 32% and the overall energy systematic efficiency 9.3%. These numbers are only half of the developed country level.3. With the sustained increase of energy consumption, the coal-dominant energy structure has caused urban air pollution while with the excessive consumption of bio-mass energy giving rise to ecological destruction, the pressure on ecological environment is more and more severe. According to the World Bank, the economic loss caused by air and water pollution in China, approximately accounts for 3%--8% of GNP.4. The energy structure is getting more and more pluralized. By the middle of the 1990’s, energy self-sufficiency rate was 98%, while at present China is the second largest crude oil importer only after USA.The rapid development of China’s economy is based on the sufficient supply of energy, however, the higher-than-normal oil price on the international market together wit h China’s ever-increasing energy demand will be a serious subject faced withChina’s development road.More than 3200 places of terrestrial heat have been discovered in China, 225 of them could be used for power generation. It is estimated that the exploitable reserve of terrestrial heat in China is equal to the power of 462.65 billion tons of standard coal. In recent years, the use of terrestrial heat in our country has increased by 7%. We have usedChina will adopt the sustainable energy development str ategy of an “energy saving prioritized, plural structured, and environment friendly” nature in the coming 20 years. We will adopt the international energy strategy and strive to quadruple GDP with double energy consumption with the help of mechanism innovation and technological advancement. The following specific goals are expected to reach under the sustained energy development strategy: energy consumption of per unit GNP will be reduced by 20% on the level of the end of the 10th five-year plan; primary energy demand will be less than 2.5 billion tons of standard coal by 2020, saving 0.8 billion tons; coal consumption ratio is controlled under 60%, renewable energy utilization reaches 525 million standard coal (power generation by renewable energy stands at 100 million kilowatt); oil importing reliance is controlled under around 60%; the reduction rate of main pollutants is 45%--60%.The Development of New Energy in ChinaNew energy and renewable energy only started to develop in China. As pointed out in the Annual Report of China’s New Energy Industry released in January, 2007, China will largely increase the rate of new energy such as wind power, solar power, and biomass power in the overall energy consumption. The report says, our first step is; the new energy installed capacity will be 120 million kw by 2020, that is 12% of China’s total installed power capacity. We will have a boost of power generation by using wind, bio-energy and solar energy. The second step is; the percentage of new energy consumption will increased dramatically comparing to other kind of energies. By 2050, the new energy will account for 30%--40% of the total energy demand of China. Now l would like to give you a brief introduction on wind power, biomass energy, solar energy and terrestrial energy in China.Wind PowerThere are abundant wind power within our huge territory and along our long coastline. According to the survey of China meteorological Academy, based on the results of 900 weather stations, there is 253 million kw of wind power reserve 10 m below our earth. There is a great potential of wind power in the coastal area of eastern China 2---15 meters below sea level. Therefor ,we have a promising future in wind power generation there.Compiled by China Energy Comprehensive Use Association and European Wind Power Society, in a Report named Wind Force 12 in China, it is expected that China will have 40 million kw of wind power capacity in 2020, if is could develop fully. Then, the wind power will go beyond nuclear power and become the third largest power source in China. If that is true, China’s annual wind power generation would go up to 80 billion kwh, it could be enough for 80 million people. Meantime, it would reduce 48 million tons of CO2 emission.The report also says that China will need over 25 thousand of large wind generators by the year 2020, wind power sale will increase to morethan 300 billion yuan, that will create at least 150 thousand of job opportunities. It indicates that in the past 5 years, the cost of wind power will reduce by 20%, its technology cost is one of the lowest which can be decreased among the renewable energies.Biomass energyAccording to the Outline for Mid-- long Term Development of Renewable Energy in China, the goal of renewable energy development in the next 15 years is; by 2020, the renewable energy will occupy 16% in the energy structure of China. Among them, the production of ethanol is going up to 10 million tons; bio-diesel fuel 2 million tons; and the major part of the biomass energy development target are bio-energy power generation, Firedamp projects biomass liquid fuel and Biomass solid fuel. The biomass project in China has made great progress now, but it is still in an initial stages.According to the Supporting Policy of Bio-energy and Bio-chemistrydevelopment jointly promulgated by several ministries, China will give favorable treatments to support biomass energy development in the following aspects: setting up risk fund system, providing flexible loss subsidy; subsidies for raw material bases and demonstration projects; tax reduction is included. We can predict that the biomass energy in China will be developed rapidly in years to come.Terrestrial Energy12604.6 GWH of terrestrial heat till 2005 with an installed capacity of 3687 MWT, which rank number 1 and number 3 in the world respectively.We use the high heat to generate power and low middle heat to daily purposes. three thermo-power plants have been build in Tibet now, the total installed capacity in China is 29 mw. Terrestrial heat Floors have seen both economical and environmental benefit in the northern part of China as well as in big or medium cities such as: Beijing, Tianjin, Xi’an and Anshan. It is growing fast in agricultural areas like green house (terrestrial),breed aquatics, irrigation, in health care, recreation and tourism ,too China tops the world in utilization of terrestrial heat, but it is only 0.5% of our total energy. Terrestrial power is only 0.35% of the world total generation. We still have a long way to go in developing and utilizing the terrestrial heat.Ocean EnergyExperts have pointed out, while we are exploring petroleum, natural gas, coal and petrification energy, China ought to focus on the future, exploring the promising ocean energy. The clean, renewable ocean energy is the key source of solving the global energy problem, exploiting of ocean energy has been aroused much attention in USA, UK and Australia, some of the experiments have entered a phase of trial operation and evaluation. However, China, Japan and other eastern Asian counties have not realized the true meaning of ocean energy exploration.China’s Energy StrategyIn order to achieve the goal of building a well-off society and face the severe challenge of the long-term energy development, it is of overriding significance for China to adopt the right energy development strategy. Drawing upon the successful experiences of the developed countries and also proceeding from its nationalcondition, China will establish a long and middle term sustainable energy strategy that is in accordance with increasing energy efficiency and protecting the environment.中国的生物质能源中国的能源蕴藏量位居世界前列，同时也是世界第二大能源生产国与消费国。

关于能源的英语作文六级

关于能源的英语作文六级英文回答：Energy is crucial for human civilization. It powers our homes, industries, and transportation systems. Without energy, modern society as we know it would cease to exist. There are many different sources of energy, includingfossil fuels, renewable energy sources, and nuclear power. Each source has its own advantages and disadvantages.Fossil fuels, such as coal, oil, and natural gas, are the most common sources of energy today. They arerelatively cheap and easy to extract, and they have a high energy density. However, fossil fuels are also a major source of pollution, and they contribute to climate change.Renewable energy sources, such as solar, wind, and geothermal energy, are becoming increasingly popular. These sources are clean and sustainable, and they do not contribute to climate change. However, renewable energysources can be intermittent, and they can be more expensive than fossil fuels.Nuclear power is a low-carbon source of energy that can be used to generate electricity on a large scale. However, nuclear power also has its risks, such as the potential for accidents and the disposal of radioactive waste.The choice of which energy source to use is a complex one. There is no single "best" source of energy, and the best choice will vary depending on the specific circumstances. However, it is clear that we need to move away from fossil fuels and towards cleaner and more sustainable sources of energy.中文回答：能源对于人类文明至关重要。

外文资料及翻译

外文翻译ANALYSIS OF HVAC SYSTEM ENERGYCONSERVATIONIN BUILDINGSABSTRACTE conomic development and people's increasing demand for energy, but the nature of the energy is not inexhaustible. Environment and energy issues become increasingly acute, if no measures are taken, then the energy will limit the rapid economic development of the question.With the improvement of living standard, building energy consumption in the proportion of total energy consumption is increasing. In developed countries, building energy consumption accounts for 40% of total energy consumption of the community, while the country despite the low level of socio-economic development, but the building energy consumption has nearly 30% of total energy consumption, and still rising. Therefore, in western countries or in China, building energy consumption is affecting the socio-economic status of the overall development of the question. In building energy consumption, the energy consumption for HVAC systems has accounted for 30% of building energy consumption -50%, with the extensive application of HVAC, energy consumption for HVAC systems will further increase Great. HVAC systems are often coupled with high-quality electric energy, and our power and relatively tight in some areas, lack of energy supply and demand which is bound to lead to further intensification of contradictions. Therefore, energy-saving heating, higher professional requirements is inevitable across the board.KEYWORDS:energy-saving，HVAC1. Energy saving design measures should be takenRapid changes in science and technology today, area HVAC new technologiesemerge, we can achieve a variety of ways of energy saving HVAC systems.1.1 Starting from the design, selecting, designing HVAC systems, so that the efficient state of the economy running.Design is a leading engineering, system design will directly affect its performance. The building load calculation is an important part of the design, a common problem is that the current design of short duration, many designers to save time, wrong use of the design manual for the design or preliminary design estimates of cold, heat load with the unit construction area of cold, heat load index, direct construction design stage as hot and cold load to determine the basis, often making the total load is too large, resulting in heating equipment, air conditioning is too large, higher initial investment, operating costs, increased energy consumption.1.2 using the new energy-saving air-conditioning and heating comfort and healthy mannerAffect human thermal comfort environment of many parameters, different environmental parameters can get the same effect of thermal comfort, but for different heat and moisture parameters of the environment of its energy consumption air conditioning system is not the same.1.3 Actual situation of a reasonable choice of cold and heat sources, seek to achieve diversification of cold and heat sourceWith the extensive application of HVAC systems on non-renewable energy consumption also rose sharply, while the broken part of the ecological environment are becoming increasingly intensified. How to choose a reasonable heating sources, has caused widespread concern of all parties.1.4 to enhance the use of hot and cold recycling of the work, to achieve maximum energyHVAC systems to improve energy efficiency is one of the ways to achieve energy-saving air-conditioning. Heat recovery system installed mainly through energy recovery, with the air from wind energy to deal with new, fresh air can reduce the energy required for processing, reducing the load, to save energy. In the choice of heat recovery, the should be integrated with the local climate Tiao Jian, Jing Ji situation, Gong Cheng actual situation of harmful exhaust gases of the situation in avariety of factors Deng integrated to determine the Xuanyong suitable heat recovery, so as to achieve Hua Jiao Shao's investment, recovery of more heat (cold) the amount of purpose.1.5 focus on development of renewable energy, and actively promoting new energyAs the air-conditioning systems used in high-grade, non-renewable energy resources and environmental problems caused by the increasingly prominent, have to develop some reasonable and effective renewable energy to ease the current tensions. To heat (cold) and solar and other renewable resources used in air conditioning and refrigeration, has certain advantages, but also clean and pollution-free. Ground Source Heat Pump is a use of shallow and deep earth energy, including soil, groundwater, surface water, seawater, sewage, etc. as a cold source in winter and summer heat is not only heating but also a new central air-conditioning system cooling.2. Saving design problemsAchieve energy-saving HVAC systems, now has a lot of mature conditions, but in practical applications there are some problems：2.1 The issue of public awareness of energy conservationThe past is not enough public understanding of energy, and on the air conditioning is also very one-sided view. For a comfort of air conditioning system or heating system, should the human body has a very good comfort. But the prevailing view now is: the colder the better air-conditioning, heating the more heat the better. This is obviously we seek the comfort of air conditioning is contrary to the view. In fact, this not only greatly increase the energy consumption of air conditioning heating, indoor and outdoor temperature and because of the increase, but also to the human body's adaptability to different environmental decline, lowering the body immunity. Therefore, we need to improve advocacy efforts to change public to the traditional understanding of air conditioning and heating, vigorous publicity and promotion in accordance with building standards and the cold heat energy metering devices to collect tolls, raise public consciousness of energy.2.2 The design concept of the problemReasonable energy-saving design is a prerequisite. At present, some designers due to inadequate attention to design empirical value when applied blindly, resulting in the increase of the initial investment, energy consumption surprising, therefore recommended that the government functions and the energy-saving review body, to increase the monitoring of the HVAC air-conditioning energy saving efforts enhance staff awareness of energy conservation design, so that energy conservation is implemented.2.3 The promotion of new technologies issueNew technology in the HVAC system for energy conservation provides a new direction. Such as ground source heat pump systems, solar cooling and heating system, not only to achieve efficient use of renewable energy, and can bring significant economic benefits, is worth promoting. However, as with any new technology, these new technologies are often high in cost, and the geographical conditions of use have certain limitations, and technically there are still many areas for improvement to improve. Therefore, new energy-efficient technologies, we should be according to local conditions, sum up experience, and actively promote.3. ConclusionHVAC systems saving energy in the building occupies a very important position, should attract enough attention to the designer. Designers should be from a design point of view fully into account the high and strict compliance with energy standards energy saving ideas to run through all aspects of the construction sector. Energy-saving technologies and renewable energy recycling, the Government and other relevant departments should support and vigorously promoted. And the design, construction, supervision, quality supervision, municipal administration and other departments should cooperate closely and pay close attention to implementing a cold, heat metering devices to collect tolls, so people really get benefit from energy efficient building, energy-saving construction and non-heating energy efficient building can not have the same charge standard. At the same time to raise public awareness of energy conservation, and vigorously promote the development of new energy-saving technologies to achieve sustainable development of society.References[1] "residential design standard" DBJ14-037-2006.[2] "Public Buildings Energy Efficiency Design Standards" DBJ14-036-2006.[3] "Technical Specification for radiant heating" JGJ142-2004.析暖通空调系统在建筑中的节能问题摘要经济的发展使人们对能源的需求不断增加,但是自然界的能源并不是取之不尽,用之不竭的。

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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 renewable 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 uranium, 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 amount 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 energy 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 to 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 gradients 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 energy, 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 world's major one-time energy World Energy Council, according to statistics, has proven oil and gas recoverable reserves, according to 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, 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, 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 polysubstation be possible to achieve widespread commercialization. Therefore, in 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 energy 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 Earth's evolution, biological reproduction and human development, plays a very important role, but also provides 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 absorbed, only half (approximately 8 ×1016 watts) of energy reaching the earth's 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 factors, 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 spaceSpace Solar Power is the first way of Engineers first proposed by P. Glaser. The basic idea is in the earth's 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 for 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 equipment 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 organizations 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, generating 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 conditions 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 economicfeasibility of the program also are 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 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.SolarSolar (Solar) generally refers to the sun's radiation energy. Carried out in the 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 launch 3.8x10 ^ 23kW power of the radiation, of which 20 billionth of the Earth's atmosphere to reach. Solar energy reaching the Earth's atmosphere, 30% of the atmosphere reflectance, 23% of atmospheric absorption, and the rest to reach the Earth's surface,Its power of 80 trillion kW, that is to say a second exposure to the sun's 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, chemical 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 world's solar energy is still the focus of the study of solar energy power plant, but the diversification 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: 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 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, 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 ofnuclear fusion reactions produce energy. Earth's orbit on the average solar radiation intensity for the 1367w / ㎡. Circumference of the Earth's equator to 40000km, and thus calculated the Earth's energy can be obtained 173000TW. At sea level standard for peak intensity 1kw/m2, a point on the Earth's surface 24h of the annual average radiation intensity 0.20kw / ㎡, which is equivalent to have 102000TW energy Human dependence on these energy to survive, including all other forms of renewable energy (except for geothermal energy resources), although the total amount of solar energy resources is the human equivalent of the energy used by ten thousand times, but low energy density of solar energy, and it vary from place to place, from time to time change, the development and utilization of solar energy which is facing a major problem. These features will make solar energy in the integrated energy system of the role of subject to certain restrictions.The use of solar cells, through the photoelectric conversion to solar energy conversion is included in electricity, the use of solar water heaters, the use of solar heat hot water and use water for power generation, using solar energy for desalination. Now, the use of solar energy is not very popular, the use of solar power costs are high there, the problem of low conversion efficiency, but for satellite solar cells to provide energy has been applied.Although the Earth's atmosphere solar radiation to the total energy only 22 billionths of a radiation energy, it has been as high as 173,000 TW, that is to say a second exposure to the sun's energy on Earth is equivalent to five million tons of coal. Earth wind energy, hydropower, ocean thermal energy, wave energy and tidal energy as well as some comes from the sun; even in the face of the earth's fossil fuels (such as coal, oil, natural gas, etc.) that is fundamentally Since ancient times the storage of solar energy down, so by including a broad range of solar energy is very large,The narrow sense is limited to solar radiation of solar light thermal, photovoltaic and photochemical conversion of the directly.Solar energy is the first time, but also renewable energy. It is rich in resources, can use free of charge, and without transportation, without any pollution to the environment. For mankind to create a new life, so that social and human energy into a era of reducing pollution.Solar cells have to respond to a light and convert solar energy to power the device. Photovoltaic effect can produce many kinds of materials, such as: single crystal silicon, polycrystalline silicon, amorphous silicon, gallium arsenide, copper indium selenium. They are basically the same principle of power generation is now crystal as an example to describe the process of light generation. P-type crystalline silicon available after phosphorus-doped N-type silicon, the formation of P-N junction. When the surface of solar light, the silicon material to be part of photon absorption; photon energy transfer to the silicon atom, electronic transitions have taken place, as a free-electron concentration in the PN junction formed on both sides of the potential difference, when the external circuit connected when the effects of the voltage, there will be a current flowing through the external circuit have a certain amount of output power. The substance of this process are: photon energy into electrical energy conversion process."Si" is our planet's abundance of storage materials. Since the 19th century, scientists discovered the properties of crystalline silicon semiconductor, it almost changed everything, even human thought, end of the 20th century. Our lives can be seen everywhere, "silicon" figure and role of crystalline silicon solar cells is the formation of the past 15 years the fastest growing industry. Production process can be divided into five steps: a, purification process b, the process of pulling rod c, slicing the process of d, the process of system battery e, the course package.Solar photovoltaicIs a component of photovoltaic panels in the sun exposure will generate direct current power generation devices, from virtually all semiconductor materials (eg silicon) are made of thin photovoltaic cells composed of solid. Because there is no part of activity, and would thus be a long time operation would not lead to any loss. Simple photovoltaic cells for watches and computers to provide energy, and more complex PV systems to provide lighting for the housing and power supply. Photovoltaic panels can be made into components of different shapes, and components can be connected to generate more power. In recent years, the surface of the roof and building will be the use of photovoltaic panels components,Even be used as windows, skylights or sheltered part of devices, which are often called photovoltaic facilities with PV systems in buildings.Solar thermalModern technology solar thermal polymerization sunlight and use its energy produced hot water, steam and electricity. In addition to the use of appropriate technology to collect solar energy, the building can also make use of the sun's light and heat energy is added in the design of appropriate equipment, such as large windows or use of the south can absorb and slowly release the sun heat the building materials .According to records, human use of solar energy has more than 3,000 years of history. To solar energy as an energy and power use, only 300 years of history. The real solar as "the near future to add much-needed energy," "the basis of the future energy mix" is the latest thing. Since the 20th century, 70s, solar technology has made rapid advances, solar energy use with each passing day. Solar energy utilization in modern history from the French engineers in 1615 in the Solomon and Germany Cox invented the world's first solar-powered engines run. The invention is a use of solar energy heating the air to the expansion and pumping machines acting.In 1615 ~ 1900, between the developed world and more than one solar power plant and a number of other solar energy devices. Almost all of these power plants collect the sun means the use of condenser, engine power is not, the working fluid is water vapor, which is very expensive, not practical value, the majority of individual studies for manufacturing solar enthusiasts. 100 years of the 20th century, the history of the development of solar energy technology in general can be divided into seven stages.化石能源和核能被认为是不可再生的能源类型。