Building Structural Control Device Helps Vibration Power Generation

By combining vibration power generation equipment and vibration amplification equipment, power generation can be increased by about 45 times.

September 16, 2010Takenaka Corporation

By using vibration amplification equipment to amplify the small vibrations generated inside and outside of a building, Takenaka Corporation (President: Toichi Takenaka) has developed a system that increases the amount of power generated by a vibration power generator. Tests of a prototype system combining a vibration power generator and a vibration amplifier at the Takenaka Research & Development Institute have shown that compared to a vibration power generator alone, the system can generate about 45 times more power.
A vibration power generator generates power from small “environmental vibrations” such as the vibrations generated during construction work, the vibrations from equipment and machinery which is continuously operating inside a building, vibrations from walking, or even vibrations from trains passing by. The scope of application for vibration power generation from environmental vibrations is becoming wider as the power consumption of electronic devices is decreasing to tens or hundreds of megawatts.
This system uses a “Tuned Mass Damper” (TMD), the type of building structural control device which is widely used in building floors, and which enables efficient power generation while controlling the shaking.

A vibrating body consisting of a weight and spring is made, and by placing this device in the part where shaking control is required, the larger the movement of the weight, the smaller the shaking in the part where the shaking control is required. By dividing the weight up, and allowing each part of the weight to move according to the different vibrating sources, a wide scope of vibration frequencies can be handled.


Enabling 45 times more power generation.

By focusing on the feature of vibration generators, whereby more power is generated as the amplitude of vibration increases, the amplitude of the vibrations that pass on to the vibration power generator was increased by about 6.7 times, enabling the amount of power being generated to increase by about 45 times.

Preventing a great drop in power generation efficiency by increasing the amplitude of vibrations over a wide scope of vibration frequencies.

The scope of application has become wider, as it has become possible to secure about four more times the scope of vibration frequencies, from the vibration frequencies where power generation efficiency is most optimum (between 25 to 30 hertz), to also include frequencies many times wider (between 22 to 42 hertz).

Able to be used in combination with any system that uses vibrations for power generation.

There are three types of vibration power generation systems: the “piezoelectric type,” which generates electricity as the elements bend, the “electromagnetic induction type,” which generates electricity as the flux changes as it passes through a coil when a magnet and coil move, and the “electrostatic induction type,” which generates electricity when the positions of electrically-charged electrodes changes. Although an electromagnetic induction type was used in the prototype, the amplifier structure used in this system can be used in combination with any type of the vibration power generation systems, enabling the system to be widely used for installation in many places and for many purposes.

【About the development】

Two of the issues regarding vibration power generators were the “small amount of power generation” and the “difference with vibration frequencies.” Vibration power generators use a minute amount of vibrations as their source of energy and were limited in the amount of power they could generate. A further problem was that because the vibration frequencies where contemporary generators could efficiently generate electricity were limited, there was a great decrease in power generation when the vibration frequency of the vibration source changed.
With this new vibration power generation system, both problems, the “small amount of power generation” and the “difference with vibration frequencies,” are overcome, enabling the installation of a vibration power generator anywhere, regardless of the place or vibration source.