February 17, 2015

Blu-ray Discs: A New Alternative for Solar Panels

Unlocking Word Meanings
 今日の単語・フレーズ

Read the following words/expressions found in today’s article. 

1. harness /ˈhɑr nɪs/ (v.) – to gain something from a source
Example: They use wind turbines to harness energy from the wind.

2. microscopic /ˌmaɪ krəˈskɒp ɪk/ (adj.) – very small and not visible to the naked eye
Example: The cells in our body are microscopic.

3. capture /ˈkæp tʃər/] (v.) – to take something
Example: The controversial research captured the attention of many scientists.

4. random / ˈræn dəm/ (adj.) – having no specific pattern, arrangement, or order
Example: The book was designed with random lines and shapes. 

5. mass /mæs/ (adj.) – relating to, affecting, or involving large numbers
ExampleMass consumption of plastic causes the rapid growth of garbage.


Article
 ニュース記事

Read the text below.
Research engineers claim that Blu-ray discs are the key to producing more efficient and inexpensive solar power systems.

A study conducted in Northwestern University found that Blu-ray discs can help solar cells obtain more light, and therefore harness more energy. This is due to the unique design of the disc’s data layer.

Data layers of Blu-ray discs are made with microscopic pits and bumps, which contain the encoded data stored in the disc. The shapes are designed to form a quasi-random pattern. Light-emitting lasers, such as those in computer disc drives, reflect on this pattern for the data to be decoded and read.

The researchers theorized that the pattern of a Blu-ray disc can capture light frequencies just like the patterns present in the layers of solar cells. Because the disc’s pattern is not too arranged or is too random, it absorbs multiple light frequencies. Light-absorbing layers with arranged patterns can only trap one light frequency, while random patterns cannot capture light frequencies long enough to be absorbed.

To test this theory, the researchers duplicated the quasi-random pattern found in the disc onto the light-absorbing layer of a solar cell they built. They then compared its productivity with that of a solar cell that has no pattern.

Results show that the quasi-random pattern increased light absorption by 21.8 percent. This also enhanced the solar cell’s power conversion by almost 12 percent. The researchers stated that all Blu-ray discs would produce the same results, since the discs are made with the same pattern. With the mass production of Blu-ray discs, researchers believe that their discovery will make solar energy systems a more affordable and practical option for all.

Viewpoint Discussion
 ディスカッションテーマ

Enjoy a discussion with your tutor.  

Discussion A

·         What other technological gadgets do you think can be helpful to the environment when recycled?
·         Among those gadgets, which would you like to recycle? Why is that so?

Discussion B

·         What do you think are the advantages of using solar panels? Please explain your answer.
·         Do you think we should invest more in solar energy? Please explain your answer.