物理专业英语_论文_中英文
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应用物理学专业英语Applied Physics: An Interdisciplinary Field with Extensive Applications.Applied physics, a branch of physics that focuses on the practical applications of scientific principles, plays a pivotal role in modern technological advancements and societal progress. It bridges the gap between theoretical physics and engineering, enabling the development and implementation of innovative solutions to real-world challenges.Scope and Methodology of Applied Physics.The scope of applied physics is vast and encompasses various subfields, including:Acoustics: Study and application of sound waves and their interactions with matter.Condensed Matter Physics: Investigation of the physical properties of solids, liquids, and amorphous materials.Electromagnetism: Exploration of the interactions between electric and magnetic fields and their practical applications.Medical Physics: Application of physics principles in medical diagnostics, treatment, and research.Materials Science: Study and design of new materials with tailored properties for specific applications.Nanotechnology: Manipulation of matter at the nanoscale to create novel materials and devices.Optics: Understanding and application of light and related phenomena, including lasers, optics, and imaging.Applied physics research methodologies typically involve a combination of theoretical modeling, experimentaldesign, and data analysis. Researchers use analytical tools, numerical simulations, and specialized laboratory equipment to investigate physical phenomena and develop practical solutions.Applications in Diverse Fields.Applied physics has far-reaching applications in a multitude of fields, including:Energy: Development of renewable energy technologies, such as solar cells, wind turbines, and fuel cells.Medicine: Advancements in medical imaging (e.g., MRI,X-ray), cancer treatment (e.g., radiation therapy), anddrug delivery systems.Materials Science: Creation of high-strength materials, lightweight composites, and smart materials for aerospace, automotive, and biomedical applications.Electronics: Design and fabrication of semiconductors,transistors, and optoelectronic devices used in computers, smartphones, and consumer electronics.Telecommunications: Development of fiber optics, wireless communication systems, and satellite technologies.Environmental Science: Monitoring and mitigation of pollution, development of sustainable technologies, and climate change research.Career Paths in Applied Physics.Graduates with a degree in applied physics are highly sought after in various industries and research institutions. Career options include:Research and Development (R&D) Engineer: Conducting research and designing new products or processes in fields such as energy, materials science, or medical physics.Product Engineer: Developing and testing new products, such as electronics, lasers, or medical devices.Technical Consultant: Providing technical expertise and guidance to businesses, organizations, or government agencies.Science Teacher: Teaching physics at the high school or university level.Patent Attorney: Specializing in patent law and representing clients in the technology sector.Conclusion.Applied physics is an indispensable discipline that enables scientific breakthroughs and technological innovations. Its interdisciplinary nature and extensive applications make it a crucial field for addressing global challenges, improving human lives, and shaping the future of technology.。
Physics is a natural science, which studies matter and energy; and how they relate to each other, and the way they affect each other over time and through space.Physics still remains one of the oldest studies of science, perhaps the oldest one due to its affiliation with astronomy. Physics have been known to be associated with others sciences such as philosophy, chemistry, and other subdivisons of mathematics and biology, but only after the Scientific Revolution, that physics was renown as a standard science. However, physics in other areas of mathematics and chemistry like for an example: quantim chemistry. The limits of physhics still remains hard to recognize.Due to new advances and technology, physics is both important and influential; because of new intelligence in physics, along with other fields sciences such as mathematics and philosophy.For instance, new developments in the field of electromagnetism led to the achievement of developing new and improved items which have radically altered urban society (such as televisions, computers and domestic appliances); developments in thermodynamics led to the production of motorized transport, and advances in mechanicas directly influenced the ideas behind calculusa basic event in physics is a magnet levitating over a superconductor, it is an example of the Meissner effect.physics helps to explain a variety of happenings, from the smallest sub-particals to vast galaxies. Also included are basic objects from which every other substance is made, and therefore physics is sometimes nicknamed the "fundimental science"physics tries to describe all the different happenings in nature by referring to simple phenomena.And this physics aims to connect the things we see around us with the root causes of those things, physics aims to connect these causes in an attempt to find why nature is as it is.An example of this would be that of the observation made by the ancient chinese where they discovered that rocks such as lodestone have a natural attraction to each other caused by an invisible force, this force was later discovered to be magnetismand was then rigorously studied in the 17th century.Not long before the Chinese, the ancient greeks knew about amber and other objects which could be rubbed with fur. These would make an invisable, similar attraction between the two, which was studied thoroughly during the 17th century. Later being called electricity.By this, it was understood by physics electricity and magnetism, both observations of nature, in their basic origin. Although further investigation, within the 19th century, did show that they were both just two versions of the same force, named electromagnetism. This particular method of joining forces is still going on today. scientists use a method to test how good a theory is. they use medical stuff,to compare how complicated it'll be, and they use previous experiments to test it. experiments results are collected and matched with their guess of how it would be.Methods are tested by scientists to see how stable there experiments work. scientists make a conclusion to what the results would be of there experiments and make an obsivation conducted to test it. The scientist would also make a prediction to there results and make a hypotheses for there work.An example of physics is if you timed differant weights to fall from differant heights, scientists would predict the times and the weights would fall and would make data of there predictions and the results.。
物理专业知识英语作文Title: The Fascinating World of Quantum Mechanics。
Introduction。
Physics, as a discipline, delves into the fundamental principles governing the universe. Among its various branches, quantum mechanics stands out as one of the most intriguing and enigmatic fields. In this essay, we will explore the key concepts and phenomena of quantum mechanics, shedding light on its profound implications for our understanding of reality.Wave-Particle Duality。
At the heart of quantum mechanics lies the concept of wave-particle duality, which suggests that particles suchas electrons and photons exhibit both wave-like andparticle-like behavior. This duality challenges ourclassical intuition, as it implies that the behavior ofparticles is inherently probabilistic rather than deterministic. The famous double-slit experiment, conducted by Thomas Young in the early 19th century and later refined with electrons and other particles, exemplifies this phenomenon. The experiment demonstrates that particles can interfere with themselves, creating an interference pattern characteristic of waves.Quantum Superposition。
英语物理文章ntroduction:English, as a global language, plays an influential role in various disciplines, including physics. This article explores the significance and benefits of English language proficiency in the field of physics education.1. The Universal Language of ScienceEnglish serves as the universal language of science, enabling scientists and researchers from different countries and backgrounds to communicate effectively. In physics, the use of English in journals, conferences, and academic settings allows for seamless collaboration and the exchange of knowledge on a global scale.2. Access to Research and ResourcesProficiency in English opens up a vast array of resources and research materials. Many scientific publications, textbooks, and online databases are predominantly available in English. This facilitates access to cutting-edge research, foundational theories, and advanced concepts that contribute to the development of physics education.3. Enhanced Communication and CollaborationClear and effective communication is crucial for anyscientific discipline, including physics. A strong command of English enables physicists to articulate their ideas, discuss complex concepts, and collaborate with colleagues from different countries. Collaborative efforts foster innovation and advancements in the field, leading to a collective understanding of physics phenomena.4. Opportunities for InternationalizationEnglish proficiency empowers physicists to take advantage of international opportunities. Attending conferences, workshops, and seminars conducted in English allows individuals topresent their research, engage in intellectual discourse, and establish professional networks. International collaborations not only enhance scientific knowledge but also promotecultural exchange and understanding.5. Enriching Educational ResourcesPhysics education heavily relies on textbooks, journals, and instructional materials. Proficient English skills enable students and educators to access a wide range of resources, including online lectures, video tutorials, and interactive simulations. These resources supplement traditional classroom teaching, making learning more engaging and comprehensive.6. Global Career ProspectsPhysics graduates with English proficiency have a competitive edge in the job market. Many multinational companies,research institutions, and academic settings require employees who can effectively communicate in English. Proficiency in English allows physicists to pursue diverse career paths and collaborate with experts from around the world.Conclusion:English language proficiency serves as an essential tool for physicists, contributing to effective communication, accessto resources, international collaboration, and career prospects. Cultivating strong English skills cansignificantly enhance physics education, further advancingour understanding of the physical world and the universe.。
物理学介绍英文作文英文:Physics is the study of matter, energy, and the interactions between them. It is a fundamental science that seeks to understand the natural world and how it works. Physics is a broad field that encompasses many different areas, such as mechanics, thermodynamics, electromagnetism, and quantum mechanics.I have always been fascinated by physics because it helps us to understand the laws that govern the universe. For example, the laws of motion discovered by Isaac Newton explain how objects move and interact with each other. These laws are used in everyday life, such as when we drive a car or throw a ball. Understanding physics can also help us to solve practical problems, such as designing efficient energy systems or building stronger structures.One of the most interesting aspects of physics is thatit allows us to make predictions about the natural world. For example, using the principles of physics, scientists were able to predict the existence of the Higgs boson particle, which was later confirmed by experiments at the Large Hadron Collider. This ability to make predictions and test them through experiments is what makes physics such a powerful and exciting field of study.中文:物理学是研究物质、能量及其相互作用的科学。
物理专业英语作文Physics: Unraveling the Mysteries of the UniversePhysics, the fundamental science that seeks to understand the underlying principles governing our universe, stands as a testament to human curiosity and the relentless pursuit of knowledge. From the minuscule particles that constitute matter to the vast expanse of celestial bodies in space, physics explores, explains, and predicts the workings of nature with remarkable precision and elegance.At its core, physics is divided into several branches, each delving into specific aspects of reality. Classical mechanics, developed largely by giants like Isaac Newton, provides the framework to comprehend motion and forces, enabling us to calculate the trajectory of a satellite or predict the fall of an apple. Electromagnetism, another cornerstone, elucidates the behavior of electric and magnetic fields, forming the basis for technologies ranging from simple circuits to advanced telecommunications systems.Quantum mechanics, born in the early 20th century amidst a revolution in scientific thought, introduces a bizarre yet incredibly accurate description of the atomic and subatomic world. Here, particles can exist in multiple statessimultaneously, and actions at a distance seem to defy intuition, challenging our everyday notions of reality. Complemented by Einstein’s theory of relativity, which reshaped our understanding of space and time, physics pushes the boundaries of comprehension, revealing a cosmos stranger than we could have ever imagined.The exploration of these theories is not merely an academic exercise. They form the bedrock of modern technology, influencing everything from the development of semiconductors and lasers to the design of medical imaging devices like MRI scanners. Furthermore, advancements in physics have led to the emergence of new interdisciplinary fields such as quantum computing, nanotechnology, and astrophysics, promising revolutionary breakthroughs in computation, materials science, and our understanding of the cosmos.Yet, despite its monumental achievements, physics retains a sense of mystery and wonder. Dark matter and dark energy, constituting the vast majority of the universe's mass-energy content, remain elusive to direct detection, hinting at the existence of physics beyond our current models. The quest for a unified theory that merges general relativity with quantum mechanics continues, fueling dreams of a 'Theory of Everything'that could unlock the deepest secrets of existence.For aspiring physicists, the journey is both thrilling and humbling. It demands rigorous mathematical proficiency, critical thinking, and a willingness to embrace complexity and ambiguity. Yet, the rewards are immeasurable. Each solved equation, every experiment that confirms a hypothesis, contributes to humanity's collective understanding and pushes the frontier of what we consider possible.physics is not just about unraveling the mysteries of the universe; it is a testament to human curiosity, creativity, and the unyielding desire to explore the unknown. Through the language of mathematics and the lens of empirical evidence, physicists continue to decode the cosmic symphony, enriching our perception of reality and shaping the future of our technological and intellectual endeavors.。
作文如何介绍物理学科英语Introduction to Physics。
Physics is a branch of science that deals with the study of matter, energy, and their interactions. It is a fundamental subject that helps us understand the world around us, from the smallest particles to the largest structures in the universe. Physics is also an essential subject for many other fields, including engineering, medicine, and technology.The study of physics is divided into several subfields, including classical mechanics, electromagnetism, thermodynamics, and quantum mechanics. Each of these subfields focuses on different aspects of the physical world and has its own set of laws and principles.The study of classical mechanics deals with the motion of objects under the influence of forces. It includes topics such as Newton's laws of motion, work and energy,and momentum. Electromagnetism, on the other hand, dealswith the interaction between electrically charged particles. It includes topics such as electric fields, magnetic fields, and electromagnetic waves.Thermodynamics is the study of heat and itsrelationship with other forms of energy. It includes topics such as temperature, entropy, and the laws of thermodynamics. Finally, quantum mechanics is the study of the behavior of matter and energy at the atomic and subatomic level. It includes topics such as wave-particle duality, uncertainty principle, and quantum entanglement.The study of physics requires a solid foundation in mathematics, particularly calculus and linear algebra. It also requires a strong analytical and problem-solvingskills, as well as the ability to think critically and creatively. Physics is a challenging subject, but it can also be very rewarding.In conclusion, physics is a fascinating subject that helps us understand the fundamental laws that govern theuniverse. It is a subject that has many practical applications and is essential for many other fields. If you have a passion for science and a love of problem-solving, then physics may be the subject for you.。
介绍物理学专业英语作文English Response:Physics is the scientific study of the behavior of matter and energy through space and time and fundamental physical interactions. It is a broad and diverse field, encompassing topics such as mechanics, heat, light, electricity, magnetism, and quantum mechanics. Physics plays a vital role in our understanding of the universe, from the smallest particles to the largest structures, and has applications in fields as varied as medicine, engineering, technology, and astronomy.The study of physics involves the use of observation, experimentation, and theoretical modeling to develop and refine our understanding of the physical world. Physicists use a variety of tools and techniques to investigate physical phenomena, including telescopes, microscopes, particle accelerators, and computer simulations. Through these methods, they have made significant contributions toour knowledge of the universe, including the development of theories such as the laws of motion, the theory of gravity, and the theory of relativity.Many famous scientists have contributed to the field of physics, including Isaac Newton, Albert Einstein, Marie Curie, and Stephen Hawking. Their work has led to major advancements in our understanding of the physical world and continues to inspire new generations of physicists.The study of physics can be challenging, but it is also rewarding. By studying physics, students develop analytical, problem-solving, and communication skills that are valuable in a variety of careers. Physics graduates can find employment in a wide range of fields, including research, teaching, engineering, technology, and finance.中文回答:物理学是科学研究物质和能量在时空中的行为和基本物理相互作用的学科。
介绍物理学专业英语作文Physics: A Journey Through the Universe of Matter and Energy.Physics, a discipline that dates back to ancient Greek philosophers like Aristotle and Archimedes, has come a long way in its understanding of the universe. It is the fundamental science that studies matter and energy, and the interactions between them. Physics is not just about equations and theories; it's about understanding how the world works.1. The Foundation of Physics: Matter and Energy.Matter is anything that has mass and occupies space. It can be solid, liquid, gas, or plasma. Energy, on the other hand, is the capacity to do work or cause change. Matter and energy are closely related, as Einstein's famous equation E=mc² demonstrates. This equation states that energy and matter are interchangeable; in other words,matter can be converted into energy and vice versa.2. The Laws of Physics.Physics is governed by laws that describe the behaviorof matter and energy. Newton's three laws of motion, for instance, explain how objects move and interact with each other. The law of gravity states that every mass attracts every other mass with a force proportional to their masses and inversely proportional to the square of the distance between them. These laws provide a foundation for understanding more complex physical phenomena.3. The Branches of Physics.Physics is a diverse field, with many sub-disciplines that focus on specific areas. Classical physics, which includes mechanics, optics, and thermodynamics, deals with the behavior of matter and energy under everyday conditions. Quantum physics, on the other hand, deals with the weirdand wonderful world of the very small, where particles behave in ways that defy classical understanding.Relativity, proposed by Einstein, deals with the behavior of matter and energy at high speeds and in strong gravitational fields.4. Applications of Physics.Physics has applications in everyday life and in various industries. It plays a crucial role in technology, from the development of computers and smartphones to the creation of advanced materials and medical imaging techniques. Physics is also essential in understanding natural phenomena like earthquakes, tsunamis, and hurricanes.5. The Future of Physics.As technology advances, so does our understanding of physics. With the development of new experimental techniques and theoretical frameworks, physicists are constantly pushing the boundaries of knowledge. They are exploring areas like quantum computing, gravity waves, and dark matter, seeking to unlock the mysteries of theuniverse.In conclusion, physics is a fascinating and fundamental science that continues to shape our understanding of the world. It is not just about equations and theories; it's about asking questions, exploring the unknown, and seeking answers. As we delve deeper into the mysteries of matter and energy, physics remains at the forefront of human inquiry and discovery.。
物电系09级1班李春恒09090201164.4:INTERNAL ENERGY OF A SYSTEM系统的内能The intemal energy of a body is defined as the energy of this body(发自自身的能量,定义为身体的能量)———the kinetic energy of the body as a whole and the potential energy of the body in the external force field.(身体的动能,作为一个整体和潜在的能量中身体的外部力场)For example,(列如)in determining the internal energy of a mass of gas,(内在确定具有的大量的气体能量)we must no take into consideration the energy of motion of the gas together with the vessel containing it,(我们必须不考虑气体运动所包含的能量)and the energy due to the gas being to in the filed of the Earth’s gravitational forces气体的能量是由于受到啦地球的引力。
Hence, the concept of internal energy includes the kinetic energy of the chaotic motion of molecules ,因此,内能的概念就是分子无规则运动的动能。
The potential energy of interaction between the molecules,and the intramolecular energy.(还包括内部无规则运动的相互作用的势能和碰撞的能量)The internal energy of a system of bodies equals the sum of the internal energues of each of then separately and the energy of interaction between the bodies.一个系统的内能包括各个部分的能量之和。
PhotovoltaicsPhotovoltaics (PV) is a method of generating electrical power by converting solar radiation into direct current electricity using semiconductors that exhibit the photovoltaic effect. Photovoltaic power generation employs solar panelscomposed of a number of solar cells containing a photovoltaic material. Materials presently used for photovoltaics include monocrystalline silicon, polycrystalline silicon, amorphous silicon, cadmium telluride, and copper indium galliuselenide/sulfide.Due to the growing demand for renewable energy sources, the manufacturing of solar cells and photovoltaic arrays has advanced considerably in recent years.Solar photovoltaics is growing rapidly, albeit from a small base, toa total global capacity of 67,400 megawatts (MW) at the end of 2011, representing0.5% of worldwide electricity demand.The total power output of the world’s PV capacity run over a calendar year is equal to some 80 billion kWh of electricity. This is sufficient to cover the annual power supply needs of over 20 million households in the world.More than 100 countries use solar PV. Installations may be ground-mounted (and sometimes integrated with farming and grazing)or built into the roof or walls of a building (building-integrated photovoltaics).Driven by advances in technology and increases in manufacturing scale and sophistication, the cost of photovoltaics has declined steadily since the first solar cells were manufactured and the levelised cost of electricity (LCOE) from PV is competitive with conventional electricity sources in an expanding list of geographic regions. Net metering and financial incentives, such as preferential feed-in tariffs for solar-generated electricity, have supported solar PV installations in many countries. With current technology, photovoltaics recoup the energy needed to manufacture them in 1 to 4 years.Solar cellsPhotovoltaics are best known as a method for generating electric power by using solar cells to convert energy from the sun into a flow of electrons. The photovoltaic effect refers to photons of light exciting electrons into a higher state of energy, allowing them to act as charge carriers for an electric current. The photovoltaic effect was first observed by Alexandre-Edmond Becquerel in 1839. The term photovoltaic denotes the unbiased operating mode of a photodiode in which current through the device is entirely due to the transduced light energy. Virtually all photovoltaic devices are some type of photodiode.Solar cells produce direct current electricity from sun light, which can be used to power equipment or to recharge a battery. The first practical application of photovoltaics was to power orbiting satellites and other spacecraft, but today the majority of photovoltaic modules are used for grid connected power generation. In this case an inverter is required to convert the DC to AC. There is a smaller market for off-grid power for remote dwellings, boats, recreational vehicles, electric cars,roadside emergency telephones, remote sensing, and cathodic protection of pipelines.Photovoltaic power generation employs solar panels composed of a number of solar cells containing a photovoltaic material. Materials presently used for photovoltaics include monocrystalline silicon, polycrystalline silicon, amorphous silicon, cadmium telluride, and copper indium gallium selenide/sulfide. Due to the growing demand for renewable energy sources, the manufacturing of solar cells and photovoltaic arrays has advanced considerably in recent years.Cells require protection from the environment and are usually packaged tightly behind a glass sheet. When more power is required than a single cell can deliver, cells are electrically connected together to form photovoltaic modules, or solar panels. A single module is enough to power an emergency telephone, but for a house or a power plant the modules must be arranged in multiples as arrays.A significant market has emerged in off-grid locations for solar-power-charged storage-battery based solutions. These often provide the only electricity available. The first commercial installation of this kind was in 1966 on Ogami Island in Japan to transition Ogami Lighthouse from gas torch to fully self-sufficient electrical power.Due to the growing demand for renewable energy sources, the manufacture of solar cells and photovoltaic arrays has advanced dramatically in recent years.Solar photovoltaics is growing rapidly, albeit from a small base, to a total global capacity of 67,400 megawatts (MW) at the end of 2011, representing 0.5% of worldwide electricity demand.The total power output of the world’s PV capacity run over a calendar year is equal to some 80 billion kWh of electricity. This is sufficient to cover the annual power supply needs of over 20 million households in the world.More than 100 countries use solar PV. World solar PV capacity(grid-connected) was 7.6 GW in 2007, 16 GW in 2008, 23 GW in 2009, and 40 GW in 2010. More than 100 countries use solar PV. Installations may be ground-mounted (and sometimes integrated with farming and grazing) or built into the roof or walls of a building (building-integrated photovoltaics).Photovoltaic power capacity is measured as maximum power output under standardized test conditions (STC) in "Wp" (Watts peak). The actual power output at a particular point in time may be less than or greater than this standardized, or "rated," value, depending on geographical location, time of day, weather conditions, and other factors. Solar photovoltaic array capacity factors are typically under 25%, which is lower than many other industrial sources of electricity.The EPIA/Greenpeace Advanced Scenario shows that by the year 2030, PV systems could be generating approximately 1.8 TW of electricity around the world. This means that, assuming a serious commitment is made to energy efficiency, enoughsolar power would be produced globally in twenty-five years’ time to satisfy the electricity needs of almost 14% of the world’s population.Current developmentsPhotovoltaic panels based on crystalline silicon modules are encountering competition in the market by panels that employ thin-film solar cells (CdTe CIGS,amorphous Si, microcrystalline Si), which had been rapidly evolving and are expected to account for 31 percent of the global installed power by 2013. However, precipitous drops in prices for polysilicon and their panels in late 2011 have caused some thin-film makers to exit the market and others to experience severely squeezed profits.Other developments include casting wafers instead of sawing, concentrator modules, 'Sliver' cells, and continuous printing processes.The San Jose-based company Sunpower produces cells that have an energy conversion ratio of 19.5%, well above the market average of 12–18%.The most efficient solar cell so far is a multi-junction concentrator solar cell with an efficiency of 43.5%produced by the National Renewable Energy Laboratory in April 2011. The highest efficiencies achieved without concentration include Sharp Corporation at 35.8% using a proprietary triple-junction manufacturing technology in 2009, and Boeing Spectrolab (40.7% also using a triple-layer design). A March 2010 experimental demonstration of a design by a Caltech group led by Harry Atwater which has an absorption efficiency of 85% in sunlight and 95% at certain wavelengths is claimed to have near perfect quantum efficiency. However, absorption efficiency should not be confused with the sunlight-to-electricity conversion efficiency.For best performance, terrestrial PV systems aim to maximize the time they face the sun. Solar trackers achieve this by moving PV panels to follow the sun. The increase can be by as much as 20% in winter and by as much as 50% in summer. Static mounted systems can be optimized by analysis of the sun path. Panels are often set to latitude tilt, an angle equal to the latitude, but performance can be improved by adjusting the angle for summer or winter. Generally, as with other semiconductor devices, temperatures above room temperature reduce the performance of photovoltaics.A number of solar panels may also be mounted vertically above each other in a tower, if the zenith distance of the Sun is greater than zero, and the tower can be turned horizontically as a whole and each panels additionally around a horizontical axis. In such a tower the panels can follow exactly the Sun. Such a device may be described as a ladder mounted on a turnable disk. Each step of that ladder is the middle axis of a rectangular solar panel. In case the zenith distance of the Sun gets zero, the “ladder” may be rotated to the north or the south to avoid that a solar panel produces a shadow on a lower mounted solar panel. Instead of an exactly vertical tower one can choose a tower with an axis directed to the polar star, meaning that it is parallel to the rotation axis of the Earth. In this case the angle between the axis and the Sun is always larger than 66 degrees. During a day it is only necessary to turn the panels around this axis to follow the Sun.The 2011 European Photovoltaic Industry Association (EPIA) report predicted that, "The future of the PV market remains bright in the EU and the rest of the world," the report said. "Uncertain times are causing governments everywhere to rethink the future of their energy mix, creating new opportunities for a competitive, safe and reliable electricity source such as PV." 2012 could see the installation of20–30 GW of PV —about the same as in 2011. Unfortunately, the industry's capacity continues to expand, to perhaps as much as 38 GW. The resulting glut of supply has crushed prices and profits. By 2015, 131–196 GW of photovoltaic systems could be installed around the globe.EconomicsThe output of a photovoltaic array is a product of the area, the efficiency, and the insolation. The capacity factor, or duty cycle, of photovoltaics is relatively low, typically from 0.10 to 0.30, as insolation ranges, by latitude and prevailing weather, and is location specific from about 2.5 to 7.5 sun hours/day. Panels are rated under standard conditions by their output power. The DC output is a product of the rated output times the number of panels times the insolation times the number of days. The sunlight received by the array is affected by a combination of tilt, tracking and shading. Tracking increases the yield but also the cost, both installation and maintenance. A dual axis tracker can increase the effective insolation by roughly 35-40%, while temperature effects can reduce efficiency by 10%. The AC output is roughly 25% lower due to various losses including the efficiency of the inverter. For example, for a 4 kW array in Paris, where the average insolation is 3.34 sun hours/day, the annual (AC) output would be approximately3.34x4x365x0.75=3657 kWh, and the monthly output, from the following chart, would range from 67 kWh in December to 498 kWh in July. The weather strongly affects the output and from year to year monthly and annual outputs can vary substantially. Published insolation values are normally 10 year averages. There are many live data sites that can be monitored, and compared.Financial incentives for photovoltaics, such as feed-in tariffs, have often been offered to electricity consumers to install and operate solar-electric generating systems. Government has sometimes also offered incentives in order to encourage the PV industry to achieve the economies of scale needed to compete where the cost of PV-generated electricity is above the cost from the existing grid. Such policies are implemented to promote national or territorial energy independence, high tech job creation and reduction of carbon dioxide emissions which cause global warming. Due to economies of scale solar panels get less costly as people use and buy more — as manufacturers increase production to meet demand, the cost and price is expected to drop in the years to come.NREL compilation of best research solar cell efficiencies from 1976 to 2010According to Shi Zhengrong, in 2012 unsubsidized PV systems already produce electricity in some parts of the world, more cheaply than coal and gas-fired power plants.[40][41] As PV system prices decline it is inevitable that subsidies will end. "Rapid decline or outright disappearance has already been seen in all the major solar markets except China and India".As of 2011, the price of PV modules per MW has fallen by 60 percent since the summer of 2008, according to Bloomberg New Energy Finance estimates, putting solar power for the first time on a competitive footing with the retail price of electricity in a number of sunny countries. There has been fierce competition in the supply chain, and further improvements in the levelised cost of energy for solar lie ahead, posing a growing threat to the dominance of fossil fuel generation sources in the next few years.As time progresses, renewable energy technologies generally get cheaper, while fossil fuels generally get more expensive:The less solar power costs, the more favorably it compares to conventional power, and the more attractive it becomes to utilities and energy users around the globe. Utility-scale solar power can now be delivered in California at prices well below $100/MWh ($0.10/kWh) less than most other peak generators, even those running on low-cost natural gas. Lower solar module costs also stimulate demand from consumer markets where the cost of solar compares very favorably to retail electric rates.As of 2011, the cost of PV has fallen well below that of nuclear power and is set to fall further. The average retail price of solar cells as monitored by the Solarbuzz group fell from $3.50/watt to $2.43/watt over the course of 2011.For large-scale installations, prices below $1.00/watt were achieved. A module price of 0.60 Euro/watt (0.78 $/watt) was published for a large scale 5-year deal in April 2012. In some locations, PV has reached grid parity, which is usually defined as PV production costs at or below retail electricity prices (though often still above the power station prices for coal or gas-fired generation without their distribution and other costs). Photovoltaic power is also generated during a time of day that is close to peak demand (precedes it) in electricity systems with high use of air conditioning. More generally, it is now evident that, given a carbon price of $50/ton, which would raise the price of coal-fired power by 5c/kWh, solar PV will becost-competitive in most locations. The declining price of PV has been reflected in rapidly growing installations, totaling about 23 GW in 2011. Although some consolidation is likely in 2012, due to support cuts in the large markets of Germany and Italy, strong growth seems likely to continue for the rest of the decade. Already, by one estimate, total investment in renewables for 2011 exceeded investment in carbon-based electricity generation.ApplicationsPower stationsMain articles: Solar parks and solar farms and List of photovoltaic power stationsMany solar photovoltaic power stations have been built, mainly in Europe.As of May 2012, the largest photovoltaic (PV) power plants in the world are the Charanka Solar Park (India, 214 MW), Golmud Solar Park (China, 200 MW), Agua Caliente Solar Project USA 100 MW) Perovo Solar Park (Ukraine 100 MW), Sarnia Photovoltaic Power Plant (Canada, 97 MW), Brandenburg-Briest Solarpark (Germany 91 MW), Solarpark Finow Tower (Germany 84.7 MW), Montalto di Castro Photovoltaic Power Station (Italy, 84.2 MW), Eggebek Solar Park (Germany 83.6 MW), Senftenberg Solarpark (Germany 82 MW), Finsterwalde Solar Park (Germany, 80.7 MW), Okhotnykovo Solar Park (Ukraine, 80 MW), Lopburi Solar Farm (Thailand 73.16 MW), Rovigo Photovoltaic Power Plant (Italy, 72 MW), and the Lieberose Photovoltaic Park (Germany, 71.8 MW).There are also many large plants under construction. The Desert Sunlight Solar Farm under construction in Riverside County, California and Topaz Solar Farm being built in San Luis Obispo County, California are both 550 MW solar parks that will use thin-film solar photovoltaic modules made by First Solar.The Blythe Solar Power Project is a 500 MW photovoltaic station under construction in Riverside County, California. The California Valley Solar Ranch (CVSR) is a 250 megawatt (MW) solar photovoltaic power plant, which is being built by SunPower in the Carrizo Plain, northeast of California Valley.The 230 MW Antelope Valley Solar Ranch is a First Solar photovoltaic project which is under construction in the Antelope Valley area of the Western Mojave Desert, and due to be completed in 2013. The Mesquite Solar project is a photovoltaic solar power plant being built in Arlington, Maricopa County, Arizona, owned by Sempra Generation.Phase 1 will have a nameplate capacity of 150 megawatts.Many of these plants are integrated with agriculture and some use innovative tracking systems that follow the sun's daily path across the sky to generate more electricity than conventional fixed-mounted systems. There are no fuel costs or emissions during operation of the power stations.In buildingsPhotovoltaic arrays are often associated with buildings: either integrated into them, mounted on them or mounted nearby on the ground.Arrays are most often retrofitted into existing buildings, usually mounted on top of the existing roof structure or on the existing walls. Alternatively, an array can be located separately from the building but connected by cable to supply power for the building. In 2010, more than four-fifths of the 9,000 MW of solar PV operating in Germany were installed on rooftops.Building-integrated photovoltaics (BIPV) are increasingly incorporated into new domestic and industrial buildings as a principal or ancillary source of electrical power. Typically, an array is incorporated into the roof or walls of a building. Roof tiles with integrated PV cells are also common.A 2011 study using thermal imaging has shown that solar panels, provided there is an open gap in which air can circulate between them and the roof, provide a passive cooling effect on buildings during the day and also keep accumulated heat in atnight.The power output of photovoltaic systems for installation in buildings is usually described in kilowatt-peak units (kWp).太阳能电池太阳能电池又称为“太阳能芯片”或光电池,是一种利用太阳光直接发电的光电半导体薄片。