The green system of power generation

Introduction
Recently, the interest in environmental problems has risen and it is accompanied
by up coming development of the green systems of power generation. In such times,“the floor which generates the electricity” which Hayami developed is high lighted bymedia. I researched it in order to understand it in detail. Then, I noticed that
piezoelectric elements are used in this system. In this paper, I will describe theexperiments I have conducted to test the effectiveness of a piezoelectric element. As aresult, I could not create big electric power from a piezoelectric element. However,there were the conditions to create bigger electric power and it could light up LEDlights. So it is possible to apply to lightings. I will try to prove that piezoelectricelements will become the green power generation in this paper.

BackgroundThe global warming
I am interested in environmental problems, especially the global warming.
Though there are some causes of the global warming, it is said that the major cause of
the global warming is carbon dioxide. There are more carbon dioxide emissions where
ever people are because, of course, people breathe. Another reason, they manufacture1

things and they transport things. I think that it is using the electricity that is the closest
cause in our life. Why dose the electricity have a relation to carbon dioxide emissions?
When you burn something, there are carbon dioxide emissions. In Japan and most othercountries, approximately half of the electricity is supplied by thermal power generations
which generate the electricity by burning coal, petroleum and so on. So the more
electricity you use, the more carbon dioxide emissions there are. Using the electricity
has a close relation to the global warming. So I try not to waste the electricity in mydaily life. However, it is impossible not to use the electricity at all because many
convenient home appliances have appeared and they are indispensable for people oftoday. From this fact, researchers have tried to reduce carbon dioxide emissions when itis generated. That was why there has been a great research in the green systems of
power generations and development of them. Photovoltaic power generation or wind
power generation is one of them. Thus I thought that I would try to research in a green
system of power generation and to make it.

Piezoelectric element
I paid attention to “the floor which generates the electricity” which was developed
by Hayami who is a representative director of Sound Power Corporation some years ago.
According to his study, “Sound power and vibration power are everywhere we live atpresent society. These energies have not been used for anything and they have been2

wasted. The technology of generation which my corporation has developed originally isable to use sound power and vibration power for generation effectively. We suggest an
ecological life style which has never appeared until now by developing various systemof generation which these technologies are applied to.” (Sound Power Corporation HP,2008, translated by me) His corporation gave this technology to Syuto highway andTokyo station and they are trying put to practical use. It is the theory that it generates byvibration when people walk or when cars move. I think it is a nice idea that energy
which has wasted still now is utilized.
I was continuing to research this system and I noticed it is piezoelectric elementsthat are used in “the floor which generates the electricity”. Usually we use apiezoelectric element for vibration by turning on electricity. To the contrary, being
applied vibration, strictly speaking pressure, it generates the electricity. I thought that it
had a possibility of a green power generation. I would like to research piezoelectricelement in detail. So I have conducted some experiments. And I will consider possibility
or future of piezoelectric element.

3Piezoelectric element

Experiments
In this section, I will illustrate the experiments which I have conducted.

Experiment ⅠThe purpose of this experiment is that I understand the character of a piezoelectricelement.

MethodFirst, I set the circuit like figure. Then I dropped a scale weight on the electricelement and I measured the voltage at that time by an oscilloscope. Then I calculated
the electric current and the electric power.

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weight

Piezoelectricelement

oscilloscope

Results
The chart shows the result of this experiment.

A super ball (13.8g)
voltage (V)electric current (A) electric power (W)height 1cm

200.0015

0.03

height 5cm

400.0025

0.1

height 10cm

600.004

0.24

5A super ball (5.0g)
voltage (V)electric current (A) electric power (W)height 1cm

150.0010.015

height 5cm

200.0015

0.03

height 10cm

400.003

0.12

An anelasticity ball (16.6g)
voltage (V)electric current (A) electric power (W)height 1cm

400.0050.2

height 5cm

400.010.4

height 10cm

500.015

0.75

A ping pong ball (2.3g)
voltage (V)electric current (A) electric power (W)height 1cm

200.00150.03

height 5cm

300.0030.09

height 10cm

400.0050.2

Moreover, an electric current when I push a piezoelectric element send anopposite direction of an electric current when I hand off.

6Analysis
The electric power depends on the height of a scale weight. The higher a scaleweight is dropped, the bigger electric power you generate. The electric power depends
on weight of a scale weight. The heavier a scale weight is dropped, the bigger electric
power you generate. The electric power depends on tough a scale weight. The harder ascale weight is dropped, the bigger electric power you generate. When a piezoelectricelement changes its shape, electric power is generated. Then, when a piezoelectricelement returns, electric power is generated. (below figure)

returnchangePiezoelectric element

Electric power

Piezoelectric element

Electric power

Experiment Ⅱ
The purpose of this experiment is that I consider what piezoelectric element
applying to.

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Method
I connected a piezoelectric element with tow LED lights like figure. Then I
tapped on piezoelectric element.
LEDLEDPiezoelectricelement

Results
Being tapped, a piezoelectric element lighted up tow LED lights.

8Analysis
A piezoelectric element can light up LED lights when it is tapped. Because anelectric current when I push a piezoelectric element send an opposite direction of anelectric current when I hand off, I made two LED lights light up stably. I apply
piezoelectric element to light up lightings like illumination.

Definition of the green power generation
I have defined what the green system of power generation is. Because it isnecessary that definitions of the green power generation are discussed before I consider
whether piezoelectric element is the green power generation. I have thought threedefinitions. First, there are not carbon dioxide emissions. We must not make carbon
dioxide emissions which cause the global warming because I think how we will stop theglobal warming. So it is an indispensable condition. Second, there is no danger topeople and nature. Without carbon dioxide emissions, we must not destroy otherenvironments. We must aim to coexist with nature. Third, the system of powergeneration is used wasting energy. There are a lot of wasting energies in a present time.
What is more, some are environmental pollutions. Unless we can make no wastingenergy, we utilize the energy. We can generate the electricity and we can keep away
pollution. It is killing two birds with one stone.

9I have thought whether the system utilized piezoelectric element is the green
power generation with these definitions. There are not carbon dioxide emissions at thephase in generation. Piezoelectric element itself is not danger to people and nature. Inaddition, vibration energy is wasting. Sometimes, it has become an environmental
pollution. We can utilize this energy. When vibration energy is changed into electricenergy, vibration energy is absorbed because of the law of the conservation of energy.
So this system is also expected as vibration pollution-control measures. That is why it isexactly the green power generation.

Evolution of piezoelectric element
I will consider that evolution of piezoelectric element. I could get only little
electric power from piezoelectric element but I think that I can get big electric power if I
come up with various ideas. I have three ideas. It can light up LED lights at the moment
when it is tipped. However, I would like to get stable electric power. So I have to store
electric power by condenser or something which can store the electricity. Besides, I
should improve high-powered piezoelectric element. Though I used piezoelectricelement on the market, it is good for this system that piezoelectric element is improved.
For example, the element can create bigger electric power and the element can catchwide range vibration. Another idea is that a high-performance system is developed. Asystem is set with some piezoelectric elements at the right place. One piezoelectric10element generates little electricity but some piezoelectric elements can generate bigelectricity if they gather. If we will be able to do so, we expect to get big electric power
and piezoelectric element can be applied in many ways. For example, the electricity inthe station is supplied by step of people, streetlights are turned on by vibration of train
and it is also possible that the home appliances which vibrate and they run on theelectricity which generate for themselves. It is a promising system. If the green power
generations like this should work well in a present society, we do not have to depend on
thermal power generation. In consequence, the world does not toward to the globalwarming.

Conclusion
Piezoelectricity element is capable of becoming a green power generation. At
present, we cannot expect to get big electric power from piezoelectric element. However,electric power from piezoelectric element depends on some conditions and it is able toput the little electric power to practical use. For example, it can light up LED light. It ispossible that the electricity from piezoelectric element is stored and that it lights up
illumination. The system with some piezoelectric elements will be developed. As aresult, we can apply wherever vibration energy is wasting. Then we can provide someelectric power. If each green power generation should supply small electric power, wewill not need to be dependent on thermal power generation. In addition, if still more11

technical innovation will happen, we can get big electric power and piezoelectricelement may be possible to cover the electric power of Japan no, possibly world.

List of Reference

株式会社音力発電 [Sound Power Corporation] Retrieved October 24. 2008, fromhttp://www.soundpower.co.jp/

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