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Text 2B. History of solar electric power

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МОСКОВСКИЙ ГОСУДАРСТВЕННЫЙ ТЕХНИЧЕСКИЙ УНИВЕРСИТЕТ

имени Н.Э. Баумана.

 

 

О.М. ЛОСЕВА, Т.А. ФУФУРИНА

 

 

RENEWABLE SOURCES OF ENERGY

 

 

ОБУЧЕНИЕ ЧТЕНИЮ НА АНГЛИЙСКОМ ЯЗЫКЕ ТЕХНИЧЕСКОЙ ЛИТЕРАТУРЫ ПО СПЕЦИАЛЬНОСТИ

«НЕТРАДИЦИОННЫЕ ИСТОЧНИКИ ЗНЕРГИИ».

 

УЧЕБНО-МЕТОДИЧЕСКОЕ ПОСОБИЕ

 

МОСКВА

Издательство МГТУ имени Н.Э. Баумана

 

Научный редактор: к.ф.н. доцент Беликова Ирина Федоровна

 


 

 

UNIT 1

New words and word-combinations:

Fossil fuels – ископаемое топливо

to run out – заканчиваться, истощаться

to keep up with the demand – идти в ногу с требованиями

consumption - потребление

harmful gases – вредные газы

vehicular pollution - загрязнение транспортом

to cause a damage – наносить ущерб

crude oil – сырье, сырая нефть

depletion – истощение, обеднение

ultimate replacement – окончательная замена

eventually – в конце концов, в конечном счете

promising - многообещающий

fusion – плавление, синтез ядер

fusion energy – термоядерная энергия

net energy yield – выход полезной энергии

Exercise 1. Give opposite meaning of the following adjectives using negative prefixes:

Renewable, conventional, polluting, expensive, important, effective, efficient, significant, nuclear, dangerous, sufficient, potential, available, serious, definite, sustainable, successful, limited.

Exercise 2. Read and translate the text 1A using a dictionary.

TEXT 1A. WHAT IS RENEWABLE ENERGY?

Can you imagine life without television, cars, or computers? What if you had to cook your dinner over a fire or fetch water from a river? It might be fun for a camping trip, but you probably would not want to do it every day. But that’s how life was before scientists and inventors discovered ways to use energy to make our lives easier.

Today, most of energy we use comes from fossil fuels. Coal, crude oil, and natural gas are all fossil fuels. Over millions of years, the decay of plants, dinosaurs, and other animals was formed into fossil fuels. These fuels lie buried between layers of earth and rock. The only way to get them out is to drill or mine for them. While fossil fuels are still being created today by underground heat and pressure, they are being consumed more rapidly than they are created. For that reason, fossil fuels are considered non-renewable; that is they are not replaced as soon as we use them. So, we could run out of them sometime in the future. Or, we might someday use so much fossil fuel that we won’t be able to drill or mine fast enough to keep up with the demand.

In the past century, it has been seen that the consumption of non-renewable sources of energy has caused more environmental damage than any other human activity. Electricity generated from fossil fuels such as coal and crude oil has led to high concentrations of harmful gases in the atmosphere. This has in turn led to many problems being faced today such as ozone depletion and global warming. Vehicular pollution has also been a major problem.

Because our world depends so much on energy, we need to find sources of energy that will last a long time. What if there was a type of energy that never ran out? There is. It is called renewable energy.

In addition, because there are so many people on earth using fossil fuels, we create a lot of pollution. So, we should also use energy sources that produce as little pollution as possible. While all energy sources cause some pollution in their creation or their consumption, renewable energy systems generally are less polluting than fossil fuel systems. Under the category of renewable energy or non-conventional energy are such energy systems as: solar, wind, geothermal, biomass, hydropower and others.

Renewable energy is the ultimate replacement for any non-renewable source. Certainly, the day will come when this fossil fuel era will pass and eventually fade totally into the history books. And what will life be like then? Even more important perhaps is what we will have to do - and even endure - to get there.

Despite nuclear energy’s role as a significant power supply source, it is highly unlikely it will survive past the 21-st century if that long. Many people are against it, storage of its highly radioactive wastes is difficult and costly, there are not enough ores available to maintain continued production of nuclear energy as it is being done today, and most of today’s nuclear plants will reach the end of their life-span within the next 50 years.

While hydro, solar, wind (a very efficient energy source), geothermal are currently our most promising forms of renewable energy to develop for future use, there are sources that many scientists classify in the “surprise category” that theoretically hold great promise. These sources range from the mining of methane hydrates (a fossil fuel that exists under the oceans and dangerous) and hydrogen fusion from simple H2O – the same process that powers our Sun and all the stars of the universe, to sources we have yet to discover. The starting potential of hydrogen fusion is so great that the US government has launched an initiative to study whether it’s feasible within the next 35 years to develop and use what’s known as fusion energy.

And, there are other fossil fuels that some scientists believe may be able to help contribute to the current energy pressures, but these forms have a low net energy yield, are difficult to process, and have serious pollution side-effects. They are oil shale and tar sands. Still, it appears unlikely that these forms will ever be used as significant sources of energy.

The Sun, no doubt, holds the greatest potential to meet the world’s energy demands. But it will take a change in the technological, political and economic landscape for it to be realized. Still, the most plausible answer for our indefinite energy needs lies in a cohesive, sensible and ecologically sustainable combination of the resources available to us. The incentives must be there to be successful – political, economic, and human intelligence – and success can be achieved only through the use of renewable energy in ways that will ensure the healthy sustainability of Earth’s life systems.

Exercise 3. Look through the text and answer the questions:

1. What did fossil fuels come from? 2. How can we get fossil fuels? 3. What does the word non-renewable mean? 3.What happened with non-renewable sources of energy in the past? 4. What is called renewable energy? Give some examples. 5. What are the perspectives of using renewable energy in the future? 6.What does the expression “surprise category” mean? 7.What success can be achieved when using the renewable energy?

Exercise 4. Translate the following word-combinations from Russian into English:

Возобновляемая энергия, потребление источников энергии, ископаемое топливо, выработка электроэнергии, вредные газы, обеднение озона, глобальное потепление, загрязнение транспортом, удовлетворять мировым требования по электроэнергии.

Exercise 5. Fill in the right word in the gap using the active vocabulary:

1.Renewable energy is so called because it relies on natural energy flows and sources in the environment will never ….

2. We create a lot of pollution by using ….

3.The … of non-renewable sources of energy has … much damage.

4.Fossil fuels are so widely used that we might not … and mine and drill them fast enough.

5.Global warming and … are two of a great amount of problems that we face today.

Exercise 6. Translate the following sentences into Russian paying attention to Complex Subject:

1.Power plants are considered to be the largest stationary source of air pollution in the United States, emitting millions of tons of sulfur dioxide, nitrous oxides and carbon dioxide each year. 2.These pollutants are believed to be the cause of global warming. 3.Nuclear energy is not likely to be the major source of world energy consumption because of public pressure and the relative dangers associated with unleashing the power of the atom. 4.Combustion of fossil fuels is considered to be the largest contributing factor to the release of greenhouse gases into the atmosphere. 5.Large members of wind generators are required to produce useful amounts of heat or electricity. 6.Wind power is thought to suffer from the same lack of energy density as direct solar radiation. 7.Wind turbines are unlikely to be erected everywhere simply because many places are not breezy enough for suitable power generation. 8.Fossil fuels, coal, oil and natural gas are said to be the three kinds of fossil fuels we have mostly depended on for our energy needs. 9.Global warming is expected to have an extensive impact on the environment. 10. Our human population seems to depend on the burning of fossil fuels to meet nearly all of its energy demands.

Exercise 7. Express your opinion and discuss the problems:

1.What kind of damage has been caused by the consumption of non-renewable sources of energy? 2. Why do we need new sources of energy?

Exercise 8. Read and translate the text 1B.

TEXT 1B. ALTERNATIVE ENERGY

There is a great deal of information and enthusiasm today about the development and increased production of our global energy needs from alternative energy sources. Solar energy, wind power and moving water are all traditional sources of alternative energy that are making progress. The enthusiasm everyone shares for these developments has in many ways created a sense of complacency that our future energy demands will easily be met.

Alternative energy is an interesting concept when you think about it. In our global society, it simply means energy that is produced from sources other than our primary energy supply: fossil fuels. Coal, oil and natural gas are the three kinds of fossil fuels that we have mostly depended on for our energy needs, from home heating and electricity to fuel for our automobiles and mass transportation.

The problem is, fossil fuels are non-renewable. They are limited in supply and will one day be depleted. There is no escaping this conclusion. Fossil fuels formed from plants and animals that lived hundreds of millions of years ago and became buried way underneath the Earth’s surface where their remains collectively transformed into the combustible materials we use for fuel.

Despite the promise of alternative energy sources—more appropriately called renewable energy, collectively they provide only about seven percent of the world’s energy needs. This means that fossil fuels along with nuclear energy –a controversial, non-renewable energy source –are supplying 93% of the world’s energy resources.

Nuclear energy, which is primarily generated by splitting atoms, only provides six percent of the world’s energy supplies. And it is not likely to be a major source of world energy consumption because of public pressure and the relative dangers associated with unleashing the power of atom. Yet, governments such as the United States see its vast potential and are placing pressure on the further exploitation of nuclear energy.

Fossil fuels exist, and they provide a valuable service. It is not so much that we use fossil fuels for energy, but it is the side effects of using them that causes all of the problems. Burning fossil fuels creates carbon dioxide, the number one greenhouse gas contributing the global warming. Combustion of these fossil fuels is considered to be the largest contributing factor to the release of greenhouse gases into the atmosphere. In the 20th century, the average temperature of Earth rose one degree Fahrenheit (1 F). This was a period that saw the most prolific population growth and industrial development in Earth’s history.

The impact of global warming on the environment is extensive and affects many areas. In Arctic and Antarctica, warmer temperatures are causing the ice to melt which will increase sea level and change the composition of the surrounding sea water. Rising sea levels alone can impede processes ranging from settlement, agriculture, and fishing both commercially and recreationally. Air pollution is also a direct result of the use of fossil fuels, resulting in smog and the degradation of human health and plant growth.

But there’s also the great dangers posed to natural ecosystems that result from collecting fossil fuels, particularly coal and oil. Oil spills have devastated ecosystems and coal mining has stripped lands of their vitality. The oil, coal and natural gas companies know these are serious problems. But until our renewable energy sources become more viable as major energy providers, the only alternative for our global population is for these companies to continue tapping into the fossil fuel reserves to meet our energy needs. And, you can pretty much count on these companies being there providing energy from renewable sources when the fossil fuels are depleted. Many oil companies, for example, are involved in the development of more reliable renewable energy technologies. For instance, British Petroleum Company (BP) has become one of the world’s leading providers of solar energy through its BP Solar division, a business that they are planning on eclipsing their oil production business in the near future.

Just how limited are our fossil fuel reserves? Some estimates say our fossil fuel reserves will be depleted within 50 years, while others say it will be 100-120 years. Nobody really knows when the last drop of oil, lump of coal or cubic foot of natural gas will be collected from the Earth. All of it will depend on how well we manage our energy demands along with how well we can develop and use renewable energy sources.

Therefore, sun, wind and water are perfect energy sources… depending on where you are. They are non-polluting, renewable and efficient. They are simple: all you need is sunlight, running water and /or wind. Not only do the use of renewable energy sources help produce global carbon dioxide emissions, but they also add some much-needed flexibility to the energy resource mix by decreasing our dependence on limited reserves of fossil fuels.

Essentially, these renewable energy sources create their own energy. The object is to capture and harness their mechanical power and convert it to electricity in the most effective and productive manner possible. There’s more than enough renewable energy sources to supply all of the world’s energy needs of forever; however, the challenge is to develop the capability to effectively and economically capture, store and use the energy when needed.

E xercise 9. Speak about the alternatives of using renewable and non-renewable sources of energy.

Exercise 10. Give the abstracts to the text both in English and in Russian.

Exercise 11. Read the text 1C and make a brief summary in English.

TEXT 1C. INCREASING AMERICA’S USE OF RENEWABLE AND ALTERNATIVE ENERGY.

A sound national energy policy should encourage a clean and diverse portfolio of domestic energy supplies. Such diversity helps to ensure that future generations of Americans will have access to the energy they need. Renewable energy can help provide for our future needs by harnessing abundant, naturally occurring sources of energy, such as the sun, the wind, geothermal heat, and biomass. Effectively harnessing these renewable resources requires careful planning and advanced technology. Through improved technology, we can ensure that America will lead the world in the development of clean, natural, renewable and alternative energy supplies.

Renewable and alternative energy supplies not only help diversify our energy portfolio; they do so with few adverse environmental impacts. While the current contribution of renewable and alternative energy resources to America’s total electricity supply is relatively small – only 9 percent – the renewable and alternative energy sectors are among the fastest growing in the United States. Non-hydropower only account for 2 percent of our electricity needs. However, electricity generation from non-hydropower renewable energy grew by nearly 30 percent in the 1990s. Continued growth of renewable energy will continue to be important in delivering larger supplies of clean, domestic power for America’s growing economy.

Renewable energy resources tap naturally occurring flows of energy to produce electricity, fuel, heat, or a combination of these energy types. One type of renewable energy, hydropower, has long provided a significant contribution to the U.S. energy supply and today is competitive with other forms of conventional electricity. However, there is limited growth potential for hydropower. Non-hydropower renewable energy is generated from four sources: biomass, geothermal, wind, and solar. The United States has significant potential for renewable resource development. These non-depletable sources of energy are domestically abundant and often have less impact on the environment than conventional sources. They can provide a reliable source of energy at a stable price, and they can also generate income for farmers, landowners, and others who harness them.

Alternative energy includes: alternative fuels that are transportation fuels other than gasoline and diesel, even when the type of energy, such as natural gas, is traditional; the use of traditional energy sources, such as natural gas, in untraditional ways, such as for distributed energy at the point of use through micro- turbines or fuel cells; and future energy sources, such as hydrogen and fusion.

Both renewable and alternative energy resources can be produced centrally or on a distributed basis near their point of use. Providing electricity, light, heat, or mechanical energy at the point of use diminishes the need for some transmission lines and pipelines, reducing associated energy delivery losses and increasing energy efficiency. Distributed energy resources may be renewable resources, such as biomass cogeneration in the lumber and paper industry or rooftop solar photovoltaic systems on homes, or may be alternative uses of traditional energy, such as natural gas micro- turbines (small combustion turbines approximately the size of a refrigerator with outputs of 25 to 500 kilowatts).

 

UNIT 2

New words and word-combinations:

to convert- преобразовывать

abundant – обильный, богатый

abundance – избыток, достаток, множество

to get squeezed tighter – сжиматься, сокращаться

to suffer from- испытывать, претерпевать, подвергаться

photovoltaic cell – фотогальванический элемент

petroleum supplies – запасы нефти

provider- поставщик

to harness – использовать, обуздывать

shareholder – акционер, владелец акций

radioactive wastes- радиоактивные отходы

advantage- преимущество

maintenance – техническое обслуживание

supervision- контроль, надзор

utility –польза, полезность, выгодность

payback time – время выплат

Exercise 1. a) Find pairs of synonyms among the given word-combinations:

Numerous, to install, quantity, to convert, to cover, abundant, thermal, to embrace, amount, heat, to locate, to transform;

b) Find pairs of antonyms among the given word-combinations:

Quick, decrease, expensive, indifference, to worsen, slow, burst of interest, to construct, increase, cheap, to improve, to break down.

Exercise 2. Read and translate the text 2A using a dictionary.

TEXT 2A. Solar Energy

Solar cells convert solar rays directly into electricity. Non-polluting photovoltaic cells use no fuel, mechanical turbine, or generator to produce electric current, and solar energy is renewable, clean, and abundant. The solar power industry has enjoyed double-digit growth in recent years, but solar energy has historically suffered from inexpensive oil, which has been cheap and easy to produce. As air pollution worsens and global petroleum supplies get squeezed tighter in the future, the world's energy providers will look to the Sun for a clean, renewable, and decentralized energy source.

Every day, the surface of planet Earth is blasted with so much solar energy that, if harnessed, 60 seconds' worth could power the world's total energy requirements for one year. The Sun is a colossal fusion reactor that has been burning for more than 4 billion years. By some estimates, the amount of solar radiation striking the earth every 72 hours is equivalent to all the energy stored in the planet's coal, oil, and natural gas reserves.

Solar radiation is a free and unlimited natural resource, yet converting it into an energy source is a relatively new idea. Using solar power for heat seems simple enough today, but it wasn't until 1767 that Swiss scientist Horace de Saussure built the first thermal solar collector. He used his solar collector to heat water and cook food. It wasn't until 1891 that the first commercial patent for a solar water heater was awarded to US inventor Clarence Kemp. The patent rights to this system were later purchased by two California executives who, by 1897, had installed the solar-powered water heaters in one-third of the homes in Pasadena, California.

Solar energy has great potential for providing clean and unlimited electricity in many regions of the world. This renewable resource has largely been ignored by many US energy providers because there has been little economic motivation due to the abundance of cheap coal and oil. Corporate shareholders want their profits today, not sometime in the distant future. In the last few decades, however, global energy demand has surged, as have the environmental problems associated with burning coal and oil and the storage of nuclear-generated radioactive waste. In the late 1990s, more governments, utilities, and corporations were embracing renewable energy sources as environmentalists, consumers, and voters pressure them to do so. More importantly, many consumers are willing to pay for "green energy," so suppliers see future profit in non-polluting renewable energy production. Some governments and energy suppliers have been slow to recognize the potential of solar power. Historically, research and development in photovoltaics has progressed erratically, in short-lived bursts of interest. For example, the US Department of Energy (DOE) funded the installation and testing of over 3,000 PV cell systems during the 1973-1974 oil embargo. By the late 1970s, energy companies and government agencies were investing in the PV industry, and an acceleration in module development took place. But solar power remained far behind oil, coal, nuclear, and other non-renewable energy sources. Serious interest in photovoltaics increased again during the 1990s after several military conflicts in the oil-rich Persian Gulf.

There are advantages to photovoltaic solar power that make it one of the most promising renewable energy sources. The system is non-polluting, has no moving parts to break down, and requires little maintenance and no supervision. The average unit produces energy for 20–30 years with low operating costs. Solar energy systems are especially unique because they require no extra construction or developed land area, and function safely and quietly. Remote or underdeveloped communities can produce their own supply of electricity by constructing as small or as large a system as needed. When communities grow, more solar energy capacity can then be added as necessary.

There are only two primary disadvantages to using solar power: a limited amount of sunlight and the cost of equipment. The value of sunlight a location receives varies greatly depending upon geographical location, time of day, season, and average cloud cover. The southwestern United States is one of the world's best areas for persistent sunshine. Globally, other areas receiving very high solar intensities include developing nations in Asia, Africa, and Latin America. Although solar energy technologies have made impressive cost improvements over the years, solar energy is currently still more expensive than traditional fossil fuel sources. However, solar energy is renewable and non-polluting, and the equipment will eventually pay for itself in 2 to 5 years, depending on how much Sun a particular location receives. Then the user will have a virtually free energy source until the end of the equipment's working life. Future improvements are projected to decrease the payback time down to 1–3 years.

As the price of solar-generated electricity decreases and as the environmental and dollar costs of petroleum increases, photovoltaics will expand its international market. Solar power will be an excellent energy option, long after Hydrocarbon Man fades away into the sunset. Clean, renewable photovoltaic-generated power enjoys obvious advantages when compared to coal, oil, natural gas, or nuclear power.

Exercise 2.Look through the text and answer the questions:

1.What is the future application of the solar energy? 2.Can solar energy meet the world’s energy requirements? Prove your point of view. 3.What was the background of using solar energy in the past? 4. Why did the providers ignore the production of this renewable source of energy? 5.What made them change their mind? 6. Are their any disadvantages of solar energy? 7. What prevails: advantages or disadvantages of solar energy?

Exercise 3. Translate the following attributive constructions into Russian:

A) direct solar heating, high-grade electricity, low capacity factor, future energy demands, consequent energy losses, overall net efficiency, overall power output,

B) total world energy demand, pumped-storage hydro-systems, base-load electricity generation, anti-nuclear environmental groups, remote area telecommunications equipment, earthbound signaling and communication equipment, actual solar collecting cells, a solar thermal power plant.

Exercise 4. Explain the meaning of the following terms:

Solar energy, mechanical turbine, energy providers, solar radiation, unlimited natural resources, solar-powered water heaters, an environmentalist, a consumer.

Exercise 5. Complete the following sentences using Gerund and translate them into Russian.

1.The world’s energy providers are interested in ….

2.Solar energy has great potential for ….

3.Many environmental problems are associated with ….

4.Energy suppliers see future profit in ….

5.Remote communities can produce their own supply of electricity by….

6.The first solar collector was used for ….

Exercise 6. Translate the following sentences paying attention to Gerund.

1.The importance of dependable electricity generation, transmission and distribution was revealed when it became apparent that electricity was useful for providing heat, light and power for human activities. 2.Electricity has been generated for the purpose of powering human technologies for at least 120 years from various sources of potential energy. 3.Turbines are usually rotated by using steam, water, wind or other fluid as an intermediate energy carrier. 4.Power generation by thermonuclear fusion has been suggested as a possible way of generating electricity. 5.A wind turbine is a device for converting wind power to mechanical rotation with a low velocity turbine designed for compressible fluids. 6.In typical land-based installations, a tower lifting the bottom of the turbine 30 meters will pay for itself by placing the turbine in faster air. 7.Renewable energy can help provide for our future needs by harnessing abundant, naturally occurring sources of energy, such as the sun, the wind, geothermal heat, and biomass. 8.The deployment of renewables may be stimulated by increasing environmental concerns over the generally much more significant global impacts of using conventional energy technologies. 9.By using wind energy to power our homes and businesses, we can strengthen our energy independence and lessen our reliance on fossil fuels. 10. Supplying low cost electricity with acceptable safety and low environmental impact will depend substantially on developing and deploying reasonably sophisticated technology.

Exercise 7. Look through the text and try to explain why solar energy systems are especially unique.

Exercise 8. Make a round table talk discussing advantages and disadvantages of solar power. Use additional material to prove your point of view.

Exercise 9. Read and translate the text 2B.

TEXT 2B. HISTORY OF SOLAR ELECTRIC POWER

Photovoltaic – basically means having the ability to convert light directly into electricity.

In 1838, physicist Edmund Becquerel, at the age of nineteen, was the first scientist to publish observations about this natural “photovoltaic” phenomenon of materials. Edmund’s reported observations were considered very interesting yet there were seemingly no practical applications.

35 years later, in 1873, Willoughby Smith first reported observing the light sensitivity of the element selenium while testing materials for underwater telegraph cables for the Telegraph Construction Company in Great Britain. The first observation of the photovoltaic effect in a solid, led to experimentation and speculation in to possible uses of a selenium solar cell.

In 1883, inventor Charles Fritz produced a solar cell with a conversion efficiency of 1-2%. This invention that produced usable electricity from sunlight caused a considerable amount of excitement for the potential use. However, industrial or commercial applications did not materialize.

By the time Thomas Edison received the first patent for incandescent light bulb in 1898, generating electricity with large turbines was the accepted standard. The research surrounding electricity at this time was more focused on the control and distribution from centralized generators and the uses of electricity. Consumer electrical product development and marketing of electrical devices became big business.

Modern solar electric power technologies came about in 1954 when Bell Laboratories experimentation with semiconductors unexpectedly found silicon doped with certain impurities was very sensitive to light. The end result was the invention of the first practical solar modules with an energy conversion efficiency of around 6 percent.

Over the last few decades, NASA has used photovoltaic cells extensively proving the technology to be an excellent means to supply electrical power for the communications, instruments, and controls in spacecraft. The current space station has a large solar electric system for generating electricity.

Photovoltaics in the 1950’s and 60’s was still considered by most as a futuristic technology appropriate only for high tech remote and special applications. This attitude was mainly due to the high expense of manufacturing the solar cells.

Photovoltaics (or ‘solar cells’) being produced today have greatly improved conversion efficiencies and much more cost efficient production methods. With today’s large scale production of solar cells the cost of the cells have now become affordable and cost efficient for many applications requiring electricity

Solar electric systems are now installed on tens of thousands of homes, businesses, communication stations, and countless other applications, supplying all or part of their electrical energy needs. Around the world many more systems are being installed every day.

Why not to begin producing clean, renewable energy for some of your power needs today?

Exercise 10. Retell the text using the following dates:

1838, 1873, 1883, 1898, 1954, 1950s and 1960s.


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