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Future Perfect: Generating electricity from sound

Generating electricity from sound

In their search for a highly efficient renewable source of energy, scientists are trying all that they can. Apart from going for solar and wind energy, they are also exploring many other alternatives as well. While doing this, they have provided us with many alternatives. From tidal energy, geothermal energy to utilizing even Hydrogen Fuel Cells, they have found many viable alternatives. However, now they are going even further with their knowledge. Scientists have even found a way for generating electricity from sound. Here’s everything you might want to know about it.

What’s happening right now

Researchers have shown that sound energy can also be converted into power for public consumption. Theoretically, every object in the universe is composed of some form of energy. As such, energy can be obtained from every other object if a proper mechanism is developed. However, very little effort has been put in generating electricity from sound and our search for the ‘green’ sources of power has been limited mostly to the exploration of solar, tidal, nuclear and wind energy.

Trends in generating electricity from sound

1. ‘Sound waves’ and biomass-powered cooker-fridge-electricity generator

SCORE device

Named the SCORE device, this technology has been developed by researchers at the University of Nottingham. This device is a compilation of a cooker, a fridge and a generator that produces electricity from sound. Burning wood is used to heat a gas-filled pipe at one end. When the gas moves from the hotter part towards the colder part, the pipe resonates and produces acoustic pressure waves that is turned into electricity.

2. Turn heat into sound and then into electricity by University of Utah physicists

Physicists at the University of Utah have developed this technology that can change heat into sound, and then sound into electricity. It could be used to change waste heat generated by various devices to electricity. They have used a very simple principle for this. The air inside an enclosed area expands when heated and increases the pressure. This air produces a clear sound when allowed to pass through a filter. The sound waves are then converted into electricity by passing through piezoelectric devices.

3. Etalim designs an engine that can harness sound waves to produce electricity

Etalim designs an engine that can harness sound waves to produce electricity

Image Source : cdn.technologyreview.com

Designed by a Vancouver based company, Etalim, this engine converts heat energy into mechanical energy, and then converts this mechanical energy to electrical energy. Instead of the traditionally used piston, this new engine uses a metal plate on which pressurized helium is placed. The sound waves traveling through the helium are amplified when it is heated and hence pushes down a metal diaphragm on a shaft to produce electricity.

4. Sharjah university students create device that produces energy from noise

Although it is still in the process of further development, this device also uses piezoelectric technology to turns sound energy into electricity. It can transform noise created by simple movements, in football stadiums or footsteps into electricity. As such, it can be widely used in noisy localities and also on roads to capture sound energy from moving vehicles.

5. Orange Sound Charge T-Shirt

Orange Sound Charge T-Shirt

Developed by the telecommunication company Orange, this technology enables you to recharge mobile phones from your T-shirt. It uses a piezoelectric film that acts like a large microphone to tap the sound pressure waves and convert them into electricity which is stored in an internal battery. This battery transmits power to your mobile phone.

6. Hydrogen fuel from sound waves

 

Scientists at the University of Wisconsin-Madison have succeeded in producing hydrogen from zinc oxide crystals and water. They immersed zinc oxide crystals in water and could harvest hydrogen from vibrations caused by passing traffic and waves. This mechanism is called the piezoelectrochemical effect.

When placed in water, the novel zinc oxide crystals react to sound-generated vibrations and develop areas with strong positive and negative charges. Later, the surrounding water molecules break up and produce hydrogen and oxygen. During this process, 18 percent of the energy from vibrations is converted into hydrogen gas. That’s really impressive when compared to 10 percent of the same coming from conventional piezoelectric materials. The research could someday enable scientists to generate green energy from sound waves at airports, oceans and from autos.

7. Sound waves for refrigeration

Sound waves for refrigerationA research team at United technologies Corporation has presented an environmentally friendly substitute for refrigeration technology. The team has worked on a compact chiller that uses sound waves to cool your goodies instead of environment-damaging chemical refrigerants. The concept uses a loudspeaker to generate high sound energy, thousands times beyond even the rock concert levels, in an environmentally safe gas to directly convert it into useful cooling in a thermo acoustic chiller. Many of the tests have been conducted by the team using air instead of refrigerants such as CFC’s to attain the cooling.

8. Voice power to charge cellphones

Voice power to charge cellphones

You might have heard one talking about solar, wind, geothermal and hydropower as our renewable energy sources. A Korean team of scientists hopes to modify the list of renewables with a chatty inclusion. They are relying on the power of speech for shoring up our most frequently used communication tool – the cell phone. Maybe at some point, the same energy could power our national electrical grids.

Scientists Young Jun Park and Sang-Woo Kim created a tiny piezoelectric material from the main ingredient of calamine lotion that is capable enough to convert sound waves into electricity. The technology hopes to reverse the process, which involves conversion of electric signals into sound.

The process could deliver the vital energy to an electrical grid by harvesting the noise of rush hour traffic. Anyhow, the scientists used zinc oxide to create a field of nanowires sandwiched between two electrodes. When the sandwich was blasted with sound waves, the sound waves generated a mild electrical current of about 50 millivolts. It’s very low when compared to what it actually needs to charge a cellphone.

The concept

The energy of the sound waves can be converted into electricity with the help of piezoelectric devices.These devices are mostly made up of crystals and generate electrical signals when exposed to pressure from sound waves. Scientists have also produced electricity from heat by using it to produce sound pressure waves and then passing it through piezoelectric devices to produce electricity.

The advantages

  • It is a renewable source of power and a ‘green’ alternative.
  • Sound pressure waves are omnipresent, even when not audible to our ears.
  • It can power small gadgets.
  • We can use it as a source of energy on the move for campers or nomads.
  • It can power street lights at a very less cost.
  • It can be immensely beneficial for the under-developed world

The impact

The fact that our day to day noises could be converted into electricity and put to some use can change the way we think of our energy future. However, it is still too early to say that sound energy can be our answer to an impending energy crisis. Having said that, we will need a multi-pronged strategy to face any crisis and sound energy could be a valid alternative.