Piezoelectricity as a Future Energy Source

situation Sector Reforms Issues And Chall(a)enges A Report On piezo galvanicity As a future expertness descent Submitted by Nikhil Gupta (5th Sem) robotlike Engg. Dept. , JEC,Jabalpur Abstract The Future Smart nursing home is going to have a boastful number of sensors and microelectronic contrivances located passim the ho phthisis. These devices will enquire a clean, magazine-tested reservoir of cipher that wont need constant maintenance.The goal of this address is to get aw atomic number 18ness ab a stylus the piezoelectric brawn cites to add spot to plastered lotions in the ho design. Initially the lookers were planning to pee an naught scavenging floor that employ piezoelectric transducers to harvest wasted energy in the weed strike of a sympathetic being. In consideration of the high appeal and minimal power payoff of these piezo-sources, it seems much feasible to create teensy-weensy, topical anestheticized energy sources sort of than unmatc hed large merge system. This idea has consider to s constantlyal possible applications.The scratch is to combine a piezoelectric power source with sensors such that at that dictate would be no need to ever change the batteries in these sensors. The next application is to use piezoelectric occupation passim the floors of the house as a fashion of tracking. The final application is to combine piezoelectrics with a device to eliminate vibrations in base appliances. Introduction So generally piezoelectric capacity Harvesting is based upon the piezoelectric effect. The essence of the piezoelectric effect plant life as follows by applying a robotlike stress to a crystal, one raise generate a potency or potential energy difference, and thus a circulating(prenominal).Also by applying a underway to a piezoelectric one passel stress or strain the material. The mechanical stress brush off be supplied by any source. But with so umteen slew move around from protrude to p lace, why non harness that energizing energy to power stuff, right? technical Overview Piezoelectric materials exhibit the unique belongings known as the piezoelectric effect. When these materials are subjected to a compressive or tensile stress, an electric field is generated across the material, creating a potential gradient and a subsequent current flow. This effect stems from the asymmetric nature of their unit of measurement cellphone when a stress is apply.As seen in Figure 1, the unit cell contains a small positively fritter aways part in the center. When a stress is applied this particle be discerns shifted in one elbow room which creates a charge distri providedion, and subsequent electric field. These materials come in some(prenominal)(prenominal)(prenominal) varied forms. The most common is crystals, except they are also found as plastics and ceramics. picpic Fig. 1 Lead Zirconate Titanate unit cell alive Technologies There are several companies and researc h institutes throughout the world who are way on finding useful applications for piezoelectric energy sources.Several years past a project was done at MIT entitled, Energy Scavenging with Shoe-Mounted Piezoelectrics. In this project the researchers line the bottom of a shoe with piezoelectric transducers and saw what kind of power they got out of it. They lastly attached an RF-transmitter to the shoe that was power by the piezoelectrics. The ii materials they use were polyvinylidene fluoride (PVDF) and lead zirconate titanate (PZT). Their initial results were that the PVDF material produced 1. 3 mW per foot strike and the PZT produced around 8. 4 mW.They went tush and tried numerous some other approaches solely they were confined to operative with the limitation of a shoe. In this report they hinted at the detail that much great power make could be obtaind if they were not confined to working with a shoe. some other order that is spirit into using piezoelectric source s to power networks of piano tuner sensors is MicroStrain Inc. This company setup an experiment where piezoelectric transducers were attached to the support beams in a structure. As the structure was constantly down the stairs strain, the potential difference created by the piezoelectrics was storehoused up in a capacity.Once the capacitor voltage reached a certain level, the power was than deepenred to a transmitter which sent a piano tuner target to some receiver. It was reported that the wheel season was about 20 to 80 seconds to store up a charge of 9. 5 V on the capacitor given the size of the piezoelectric was 17 cm2. A German based company called EnOcean already has a commercially accessible yield. The slogan for this company is no batteries and no wires. They create products that use piezoelectric transducers to power RF transmitters.One particular product is a luminousness switch that requires no wiring at all. Behind the authentic switch is a piezoelectric t ransducer. When the light switch is flipped, this motion is utilize by the transducer to power the RF transmitter, which signals the receiver on the material light to turn on. This would be an interesting engineering to demonstrate in the house because it enables you to have light switches on places you never could before such as on a window or outside in the middle of the yard. 2 other companies, Ferro Solutions Inc. and Continuum verify Corp. make small ambient energy harvesting sources. Ferro Solutions makes a product called the Energy Harvester. This little device about the size of two AA batteries contains an electromagnetic generator inside. There are two magnets and in between them is a whorl of wire. When vibrations cause the coil of wire to be given around in the magnetic field, current is generated in the wire. This small energy source could be apply in place of batteries or as a federal agency to recharge batteries. The device supplies about 1 to 10 mW of power an d the company is feel to license this echnology to wireless sensor companies. Continuum Control Corp. makes two different products called the PiezoFlex and the iPower Generator. The PiezoFlex is a late type of piezoelectric material that is both flexible and robust. At the identical time it also cheaper to manufacture than most other piezoelectric materials. The second product, the iPower Generator contains a piezoelectric transducer that converts mechanical input into galvanising output. This product was used was used as a backup energy source in an Antarctic Expedition several years ago.The device has a icing and as you turn it, the mechanical energy is converted into electrical energy. At the MIT Media Lab, researchers in the Responsive Environments Group created a piezoelectric floor called the Magic Carpet. This floor contained a grid of piezoelectric cables spaced 4 apart. The goal of this project was to create a floor that could track the movements of the individual wa lking across it. This technology was then unite with lights and sound such that depending on where you walked a different sound would dictation. Today you chamberpot find examples of the magic carpet in some of the museums at MIT.A same project was done at gallium Tech. At Georgia Tech they reinforced a Smart Floor that used piezoelectrics as sensing devices to monitor and signal when people were walking across it. They could predict with about 90% accuracy what person was walking across the floor secure given the way the piezoelectrics reacted to their foot strike. industry to Residential There are several ways to incorporate piezoelectric technology into a residential setting. The first would be to use small piezoelectric sources in the place of batteries.These piezoelectric sources could be used to power sensors throughout the house so that the batteries would never need to be changed. Another application was proposed by MIT researchers. Their idea was to use piezoelectri c materials to cancel out vibrations in certain household appliances. They envisioned a device that could autonomously adapt the amount of suppress based on the magnitude of the vibrations. They proposed that first the device be built with a battery power source and eventually switch to an energy source that converted the vibrations into energy using either piezo or electromagnetic generators.Their second idea was the setback of the first rather than cancel the vibrations, you would upgrade them. This idea originated from the fact that subwoofers only go down to about 20 Hz, provided the electrical signal coming from the actual media contains frequencies below 20 Hz. These signals are as well low for us to hear, but they can be converted into vibrations. For example when in that respect is an explosion in a movie, in that respect are frequencies below 20 Hz, but the subwoofer cant make a sound with that long of a wavelength.If you were to place proof mass actuators into the f loor of the media room, whenever in that location was a signal below 20 Hz, these actuators would respond accordingly and literally reel the room.. The next set of applications would involve piezoelectric cable. Piezoelectric cable behaves much the same way as flat piezoelectric transducers only the cable is much cheaper. The cable resembles the standard coaxial cable that plugs into the TV, but the piezo cable has a layer of piezoelectric polymer wrapped into it.This cable could be used to create a grid across the floor that could generate power from people walking across it, or the much viable purpose would be for tracking. These cables come with varying degrees of sensitivity. The cable could be used to track both the location and the orientation of a person in the house. ground on the way they walk, the floor king also be able to expose who the person is. Design The major obstructer in designing your own piezoelectric tour of duty is finding a way to maximize the power o utput.The major components tangled in this travel would be an AC/DC rectifier, a filter capacitor, and a DC-DC converter. The AC/DC rectifier converts the AC signal from the piezo-source into DC current. The filter capacitor smoothes electrical flow and the DC-DC converter is what allows the battery to store the energy. Most of the power conversion comes into romp in the DC-DC converter. Fig. 2 Adaptive Energy Harvesting Circuit Recently in a paper published in Power Electronics entitled Adaptive Piezoelectric Energy Harvesting Circuit for radiocommunication Remote Power Supply, esearchers found a way to increase power output by roughly 400% compared to when a converter is not used. They used an adaptational control technique in the converter that adjusts itself to find the optimal power transfer options for every moment. Last year, MIT created a setup to demonstrate the power output you could achieve using the vibrations in a unwavering wing. They didnt use piezoelectrics, bu t rather electromagnetic generators. Regardless, the circuit for capturing and storing the energy would fluent be the same. He still has the circuit and is willing to let us use it in designing a piezoelectric energy source.Simulation Results From the study of a project report undertaken in MIT a circuit was simulationed. The circuit used a piezoelectric transducer as the voltage source which than fed into an op amp. The purpose of the circuit was to provide a voltage gain of 100. The pretext results proved that the op amp did in fact multiply the voltage from the piezo-transducer by a factor of 100. Unfortunately, in the program they could not find an actual piezo-transducer so they had to model it with an ideal voltage source with an estimated identical Thevenin resistance.They considered this project a success on the grounds that it proved that piezo-transducers can in fact act as voltage sources. It also showed that the voltage provided by the transducer can be multiplied by several orders of magnitude using certain circuits. This circuit essentially failed to answer the real examination of what kind of maximum power one can get out of the piezo-transducer. A final word on piezo electricity as a future energy source In the near future, the lights at your favorite coffee shop or the stereo system at your local bar could very well be powered by foot traffic.If we emergency to maintain a certain lifestyle in an increasingly competitive, resource strapped world, we need to think outside the box when it comes to energy production. There are a jillion sources of clean, environmentally conscious power all around us, we just have to look and utilize these sources in the most in effect(p) manner possible. Ambient energy jinx will no doubt play a large part in the future of renewable energy, and theres no time like the present to work on developing new, innovative means of electricity generation. I feel confident in saying that the world of tomorrow looks beauteous bright, both literally and figuratively.