energy management

Piezoelectric effect : 

Piezoelectric effect Discovered in 1880 by Jacques and Pierre Curie during studies into the effect of pressure on the generation of electrical charge by crystals (such as quartz). Piezoelectricity is defined as a change in electric polarization with a change in applied stress (direct piezoelectric effect). The converse piezoelectric effect is the change of strain or stress in a material due to an applied electric field.

What is a crystal? : 

What is a crystal? A class of materials arranged in a definite, geometric pattern in three dimensions (table salt and sugar are common examples) Quartz Crystal is silicon and oxygen arranged in a crystalline structure (SiO2). SiO2 is also found abundantly in nature in a non-crystal structure (“amorphous”) as sand.

A method for predicting the behavior of a crystal: The unit cell : 

A method for predicting the behavior of a crystal: The unit cell + Represents silicon atom - Represents oxygen atom Not actually correct, but this method allows a good understanding of quartz crystals

Slide 5: 

The unit cell of crystal silicon dioxide - + + - + -

Slide 6: 

- + + - + - - + + - + - + - A pushing force: (: compression) A pulling force: (: tension) + -

Slide 7: 

Crystal Current Meter = 0 Charges cancel each other, so no current flow Crystal material at rest: No forces applied, so net current flow is 0 + - + - + - + - + - + -

The Piezoelectric Effect : 

The Piezoelectric Effect Crystal Current Meter deflects in + direction - - - - - + + + + + Due to properties of symmetry, charges are net + on one side & net - on the opposite side: crystal gets thinner and longer Crystal material with forces applied in direction of arrows……….. Force

The Piezoelectric Effect : 

Crystal Current Meter deflects in - direction + + + + …. Changes the direction of current flow, and the crystal gets shorter and fatter. Changing the direction of the applied force……….. Force - - - - - The Piezoelectric Effect

Slide 10: 

Unit Cell at Rest Neutral Charge Unit Cell Under Mechanical Compression (“pushing” force): Electrical polarity as shown Unit Cell Under mechanical Tension (“pulling” force): Electrical polarity reverses. + + + - - - + + + - - - +

Slide 12: 

A length of one kilometer along a single lane would produce 200 KWh, while a four-lane highway could produce about a 1MWh – sufficient electricity to provide for the average consumption in 2,500 households. Source: http://www.engadget.com/2008/12/13/prototype-piezoelectric-road-could-generate-power-by-simply-sitt/

Slide 13: 

Total length in India of road and rail-network is 1,33,000 km will produce 2,66,00,000 kwh then electricity to provide for the average consumption in 33,25,00,000 households.