Technical English Episode 3 LARGE WINDOWS COULD CAPTURE SOLAR ENERGY

Large Windows Could Capture Solar Energy Before reading the text Solar cell is a normal battery. Solar cell can produce energy under light only. Solar cells are very cheap. Solar cells can run a big machine. Solar powered devices have a combination of solar cells. Solar cells are the only alternative to fossil fuels. _True_ False No idea ______ _______ ________

Large Windows Could Capture Solar Energy Solar cells have been around since the 1950s. But now there is a race to develop transparent solar cell that can cover windows of buildings and still capture the sun’s light for electricity. Different kinds of light from the sun There are three kinds of light that reach our planet from the sun. They are ultraviolet light, or UV, visible light, and infrared light. Together they make up what is called the solar spectrum. Troy Townsend is a solar cell researcher at St. Mary’s College of Maryland. He says working with the transparent solar technology for windows means you cut the efficiency in half. That is because you are letting visible light—light you can see—pass through the solar cells instead of capturing and using that light to make electricity. That leaves only light from the ultraviolet and infrared parts of the light spectrum to make electricity. He spoke to VOA via Skype. “One of the major challenges with transparent solar cells is developing a system that would allow you to absorb the maximum amount of UV and the maximum amount of infrared.”

Large Windows Could Capture Solar Energy Because glass absorbs UV light, Townsend says the efficiency will drop even more, if the solar cell is on the inside of the window. But if the cell is put on the outside of the window, it could capture the light before it goes through the glass. That would require the cell to be protected from the elements of heat, moisture, and cold. Townsend says the trick would be to find a clear material that would cover the cell—and still let the light come through. Developing Photovoltaic Cells for Windows Several colleges and private laboratories are working to develop photovoltaic compounds that could be applied to windows. They would be transparent, which means, you can see through them. So they would be able to collect the sun’s energy without blocking the view through the window. SolarWindows Technologies in Maryland says it has developed an efficient transparent solar cell. John Conklin is head of the company. “We have actually taken a technology, organic photovoltaics, and innovated it into transparent technology, applied it to window glass and turned a passive window into an active electricity generating window.”

Large Windows Could Capture Solar Energy Conklin says a solar window can be totally transparent. Or it could be tinted, or colored, which makes it more efficient. "We can make the color darker or lighter, or blend the colors to go with the blue-green, a green-grey, a brown, depending on what the architect, the building owner or the building developers is looking at.” Conklin says his company is working with the U.S. Department of Energy to test and develop the technology. And he plans to have a commercial-ready product by the end of 2017. If he is successful, Conklin says his electricity-making window could pay for itself in one year. According to a 2012 survey, there are 5.6 million commercial buildings in the U.S. They have more than 8 billion square meters of windows. Even if only a part of that glass could collect power from the sun, it could greatly lower the need for polluting fossil fuels.

Words to Learn USEFUL EXPRESSIONS Underline the words you do not know. transparent ultraviolet infrared Solar spectrum efficiency absorb capture moisture photovoltaic blocking innovate Tint commercial trick renewable energy USEFUL EXPRESSIONS cut the efficiency efficiency drop to be protected from a commercial-ready product lower the need

transparent : trænˈspærənt Definition: Something that you can see through Sample sentence: The box has a transparent plastic lid so you can see what's inside.

transparent : trænˈspærənt

ultraviolet : /ˌʌltrəˈvaɪəlɪt◂/ Definition: ultraviolet light cannot be seen by people, but is responsible for making your skin darker when you are in the sun Sample sentence: It will investigate the shorter-wavelength radiation from the objects observed by the ultraviolet telescope.

ultraviolet : /ˌʌltrəˈvaɪəlɪt◂/

infrared : /ˌɪnfrə ˈred◂/ Definition: infra-red light gives out heat but cannot be seen Sample sentence: Herschel had found the infra-red detected invisible light in the form of radiant heat.

infrared : /ˌɪnfrə ˈred◂/

spectrum : /ˈspektrəm/ Definition: the set of bands of coloured solar light into which a beam of light separates when it is passed through a prism

spectrum : /ˈspektrəm/

efficient : /ɪˈfɪʃənt/ Definition: If someone or something is efficient, they work well without wasting time, money, or energy Sample sentence: We aim to provide our clients with an efficient and friendly service.

efficient : /ɪˈfɪʃənt/

absorb : /əbˈsɔːb, əbˈzɔːb $ -ɔːrb/ Definition: to take in liquid, gas, or another thing from the surface or space around something Sample sentence: Plants absorb nutrients from the soil.

absorb : /əbˈsɔːb, əbˈzɔːb $ -ɔːrb/

capture : /ˈkæptʃə $ -ər/ Definition: To catch and keep Sample sentence: Cameras have already captured the image.

capture : /ˈkæptʃə $ -ər/

moisture : /ˈmɔɪstʃə $ -ər/ Definition: small amounts of water that are present in the air, in a substance, or on a surface Sample sentence: Moisture is essential for keeping your skin fresh and youthful.

moisture : /ˈmɔɪstʃə $ -ər/

photovoltaic : /ˌfəʊtəʊvɒlteɪ-ɪk / Definition: generating electricity directly from sunlight by a an electronic process naturally occurring in semiconductors

photovoltaic : /ˌfəʊtəʊvɒlteɪ-ɪk /

innovate : /ˈɪnəveɪt/ Definition: to start to use new ideas, methods, or inventions Sample sentence: The company has successfully innovated new products and services.

innovate : /ˈɪnəveɪt/

tint : /tɪnt/ Definition: Sample sentence: a small amount of a particular colour Sample sentence: paper with a yellowish tint

tint : /tɪnt/

renewable energy : /rɪˈnjuːəbəl ˈenədʒi / / rɪˈnuː- ˈenədʒi / Definition: energy that is produced using the sun, wind, etc., or from crops, rather than using fuels such as oil or coal Sample sentence: What are the environmental benefits of renewable energy?

renewable energy : /rɪˈnjuːəbəl ˈenədʒi / / rɪˈnuː- ˈenədʒi /

commercial : /kəˈmɜːʃəl $ -ɜːr-/ Definition: related to business and the buying and selling of goods and services Sample sentence: Many commercial companies are having financial difficulties.

commercial : /kəˈmɜːʃəl $ -ɜːr-/

Assignment - Assessment Learn all vocabulary. Listen to the text 10 times while reading, and listen to the same text 10 times without reading. Then record your voice while reading. Undersand the text deeply (TEXT ANALYZING) Write the text on the right of your notebook, then analyze it on the left... .. verbs, tense, plural nouns, - my favourite sentence, good expressions, words to learn 6. Summarize the text

ASSIGNMENT Make a sentence with the given expressions Solar spectrum Solar cells To absorb the maximum amount Efficiency drop Blocking the view Passive window Totally transparent Develop technology