VOL 3

WHAT IS ELECTRICAL ENGINEERING?
Amal Basha
S1S2 EEE

ELECTRICAL ENGINEERS design power systems and complex electronic circuits. ELECTRICAL ENGINEERING is a professional engineering discipline that deals with the study and application of electricity, electromagnetism and electronics. The field first came to public attention in the late 19th century with the installation of the first large scale electric supply and now encompasses a range of sub-disciplines including power, control systems, electronics and telecommunications. ELECTRICAL ENGINEERING is considered to deal with the problems associated with large-scale electrical systems such as power transmission and motor control where as electronics engineering deals with the study of small-scale electronic systems including semiconductors and the design of integrated circuits.
After the discovery of electricity in the 17th century, scientists began studying its potential applications, and by the 19th century, innovators like Nicolas Tesla and Thomas Edison began using electricity for motors and telegraphy. Advances in radio technologies soon followed, and by the middle of the 20th century, early computers and integrated circuits had been invented. Meanwhile, universities were developing formal programs of study, and today, the field’s practitioners, called electrical engineers generally hold an academic degree and may be certified by a professional body.
The main sub-disciplines of ELECTRICAL ENGINEERING are
Power engineering
Control systems engineering
Electronics engineering
Telecommunication engineering

POWER ENGINEERING
It deals with the generation, transmission and distribution of electricity as well as the design of a range of related devices including transformers, electric generators and motors. In many regions of the world governments maintain an electrical network called a power grid. Users purchase electrical energy from the grid avoiding the costly exercise of having the generator their own. Power engineers may work on the design and maintenance of the power grid as well as the power systems that connect to it. Such systems are called on-grid power systems and may supply the grid with additional power, draw power from the grid or do both. Power engineers may also work on systems that do not connect to the grid, called
off-grid power systems, which in some cases are preferable to on-grid systems.

CONTROL ENGINEERING
It focuses on the modeling of a diverse range of dynamic systems and the design of controllers that will cause these systems to behave in the desired manner. To implement such controllers electrical engineers may use electrical circuits, digital signal processors and micro controllers. Control engineering has wide range of applications in the flight and propulsion systems of commercial airlines to the cruise control present in many modern automobiles. Control engineers often use feedback when designing control systems. In an automobile with cruise control the vehicle speed is continuously monitored and fed back to the system, which adjusts motor speed accordingly.

ELECTRONICS ENGINEERING
It involves the design and testing of electronic circuits that use the properties of components such as resistors, capacitors, inductors, diodes and transistors to achieve a particular function. Prior to the Second World War the subject was commonly known as radio engineering and basically was restricted to aspects of communications and radar. At this time study of radio engineering at universities could only be undertaken as part of a Physics degree. Later in past war years, as consumer devices began to be developed, the field broadened to include modern TV, audio systems and latterly computers and microprocessors. In the mid to late 1950s, the term radio engineering gradually gave way to the name electronics engineering which then became a stand alone university degree subject, usually taught alongside electrical engineering with which it had become associated due to some similarities. Before the invention of the IC in 1959 electronic circuits were constructed from discrete components that could be manipulated by humans. These circuits consumed much space and power and were limited in speed. By contrast IC packs a large number of electrical components, mainly transistors into a small chip. This allowed for the powerful computers and other electronic devices, which we see today.

TELECOMMUNICATION ENGINEERING
It focuses on the transmission of information across a channel such as a coaxial cable, optical fibre or free space. Transmission across free space require information to be encoded in carrier wave inorder to shift the information to a carrier frequency suitable for transmission and this is known as modulation. Popular analogue modulation techniques include AM and FM.
Once the transmission characteristics are determined telecommunication engineers design the transmitters and receivers needed for such systems. These two are sometimes combined to form a two-way communication device known as transceiver. A key consideration in the design of transmitters is their power consumption as this is closely related to their signal strength. If the signal strength of a transmitter is insufficient the signals information will be corrupted by noise.

Superconductivity &Maglevs

Cibumol.B.Babu
Indu.J.R
S6EEE Superconductivity is a phenomenon displayed by certain conductors that demonstrate no resistance to the flow of an electric current. Superconductors also exhibit strong diamagnetism that is, they are repelled by magnetic fields.Superconductivity was first discovered in 1911 by the Dutch physicist Heike Kamerlingh Onnes, who observed no electrical resistance in mercury below 4.2 K The phenomenon was better understood only after strong diamagnetism was detected in a superconductor by Karl W. Meissner and R. Ochsenfeld of Germany in 1933. The basic physics of superconductivity, however, was not understood until 1957, when the American physicists John Bardeen, Leon N. Cooper and John R. Schrieffer advanced the now celebrated BCS theory
Because of their lack of resistance, superconductors have been used to make electromagnets that generate large magnetic fields with no energy loss. Super conducting magnets have been used in studies of materials and in the construction of powerful particle accelerators. Using the quantum effects of superconductivity, devices have been developed that measure electric current, voltage, and magnetic field with unprecedented sensitivity. The discovery of better super conducting compounds is a significant step towards a far wider spectrum of applications, including faster computers with larger storage capacities, nuclear fusion reactors in which ionized gas is confined by magnetic fields and more efficient generation and transmission of electric power..
Magnetic Levitation above a Superconductor
A small cylindrical magnet floats above a high-temperature superconductor. The vapour is from boiling liquid nitrogen, which keeps the superconductor in a zero-resistance state. As the magnet is lowered towards the superconductor, it induces an electric current, which creates an opposing magnetic field in accordance with Ampere’s law. Because the superconductor has no electrical resistance, this induced current continues to flow, keeping the magnet suspended indefinitely.


Applications The most important early application of high-temperature superconductors has been in communications. Combined with low temperature electronics at 60K, super conducting thin-film devices (microwave filters) enhance the performance of mobile telephone systems giving greater sensitivity, selectivity and protection from 'drop-outs'. There are at least four American start-up companies successfully exploiting this technology, one of them using materials developed in the UK. A British company, Cry systems, employing filters developed at Birmingham University, aims to commercialise such systems in Europe and Asia.
Another exciting application goes to the quantum heart of superconductivity. The magnetic field, or flux, passing through a small loop of super conducting material is quantised and can be used to represent the 1s and 0s on a digital computer. This is the basis of an entirely new kind of very low power switch, called a rapid single flux quantum (RSFQ) device, which could revolutionise computing. RSFQ circuitry operating several hundred times faster than today's most advanced computers has already been demonstrated. It could be an attractive route towards the petaflop computer capable of doing 1015 arithmetical operations a second, requiring only a kilowatt of power rather than the megawatt quantity currently envisaged using silicon technology.
Related devices called super conducting quantum interference devices, or SQUIDs, can be used diagnostically to detect the minute magnetic fields produced by the brain or heart, while other variations of this super conducting technology are employed in ultra-sensitive microwave communications, astronomy, and analysis for pharmaceutical industry.
Magnetic Levitation Train (MAGLEV)


Maglevs, are faster, smoother, and quieter than conventional trains. Several countries, including Germany, Japan, and the United States, have maglev development programmes. This magnetic levitation train, which is under development in Germany, can reach speeds of 435 km/h.
Magnetic Levitation Train (MAGLEV)

The most exciting of all the applications of superconductivity is the Magnetic Levitation Train or Maglev Train which is a high-speed ground vehicle levitated above a track called a guideway and propelled by magnetic fields. Magnetic levitation train technology can be used for urban travel at relatively low speeds (less than 100 km/h), a short-distance maglev shuttle has been operating in Britain since 1984, between Birmingham's airport and railway station. However, the greatest worldwide interest is in high-speed maglev systems. Train speeds of 517 km/h have been demonstrated by a full-size maglev vehicle in Japan, while in Germany a maglev train has run at 435-km/h .Two different approaches to magnetic levitation train systems have been developed. The first, called electromagnetic suspension (EMS), uses conventional electromagnets mounted at the ends of a pair of structures under the train; the structures wrap around and under each side of the guideway. The magnets are attracted up towards laminated iron rails in the guideway and lift the train. However, this system is inherently unstable; the distance between the electromagnets and the guideway, which is about 10 mm, must be continuously monitored and adjusted by computer to prevent the train from hitting the guideway. A 31.5-km track in Emsland, Germany, is currently testing this approach.
The second design, called electrodynamics suspension (EDS), uses the opposing force between magnets on the vehicle and electrically conductive strips or coils in the guideway to levitate the train. This approach is inherently stable, and does not require continued monitoring and adjustment; there is also a relatively large clearance between the guideway and the vehicle, typically 100 to 150 mm. However, an EDS maglev system uses super conducting magnets, which are more expensive than conventional electromagnets and require a refrigeration system in the train to keep them cooled to low temperatures. Both EMS and EDS systems use a magnetic wave traveling along the guideway to propel the maglev train while it is suspended above the track.
Maglev systems offer a number of advantages over conventional trains that use steel wheels on steel rails. Because magnetic levitation trains do not touch the guideway, maglev systems overcome the principal limitation of wheeled trains—the high cost of maintaining precise alignment of the tracks to avoid excessive vibration and rail deterioration at high speeds. Maglevs can provide sustained speeds greater than 500 km/h, limited only by the cost of power to overcome wind resistance. The fact that maglevs do not touch the guideway also has other advantages: faster acceleration and braking; greater climbing capability; enhanced operation in heavy rain, snow, and ice; and reduced noise. Maglev systems are also energy-efficient on routes of several hundred kilometers length, they use about half as much energy per passenger as a typical commercial aircraft. Like other electrical transport systems, they also reduce the use of oil, and pollute the air less than aircraft, diesel locomotives, and cars.
Current plans for high-speed maglev systems include a 283-km route from Berlin to Hamburg. In Japan, a 43-km maglev test track is under construction in Yamanashi Prefecture, about 100 km west of Tokyo. When tests on the latest maglev vehicle have been completed, the test track is planned to be extended to Tokyo and Osaka. This new commercial line will relieve passenger demand on the Shinkansen high-speed train, which currently operates at peak speeds of 225 km/h.
In the United States, much of the interest in maglev systems has been initiated at the state level, with plans developed in Florida, California, Nevada, New York, and Pennsylvania. Studies completed by the federal government in 1993 concluded that the potential benefits of a maglev system justified starting a national development programme.Maglevs can have better improvement with the introduction of duper superconductivity.


No time to loose

Deepthi Bhanujan
S1S2 EEE
A silent crisis
One hour inside the bustling hospital waiting room of the regional cancer center is enough to explain the emerging cancer crisis. People are simply living longer and the incidence of adult cancers and the demand for radiotherapy services is accelerating.
More than 10 million people are diagnosed with cancer each year. Over half of these cases occur in developing countries, where cancer incidents are increasing dramatically. Globally, cancer
Kills more people than AIDS, tuberculosis and malaria put together. Most poor countries remain seriously under served with the therapies designed to save lives or at least improve their quality of life. Developing countries make 85% of the world population’ yet they have only about one-third of the total radiotherapy facilities-a small fraction of the estimated need.
The most common cancer in the world is lung cancer; the most common among women is breast cancer. There are significant differences in how cancer strikes people in various parts if the world. Such variations may be due to smoking, dietary and other social habits and because people inherit different kinds of genetic mutations from their parents.
The best time to diagnose a cancer is before the person feels that something is wrong. In some cases, by way of screening patients, it is possible to diagnose cancer that are very small and have a high probability of successful treatment. Unfortunately, too few people, especially in developing countries, undergo screening due to either lack of awareness or lack of resources or both.
All too often, cancer is suspected only when it has grown large enough to produce symptoms, such as a cough, a lump, a sore or bleeding. A full physical examination and other tests are usually necessary to determine the “stage” of cancer-ie, how big it is and how much it has spread in to the neighbouring organs.
Radiotherapy is the treatment of cancer and other diseases with ionizing radiation. Ionizing radiation deposits energy that injures or destroys the cells in the area being treated by damaging the genetic material, making it impossible for these cells to reproduce.
One type of radiotherapy commonly used involves the use of machines-usually cobalt machines or linear accelerators-to shoot photons or high-energy electrons from outside the body into a cancer-site. This is called External Beam Radiotherapy. Another technique for attacking cancer cells is to place radioactive implants directly into a tumour or body cavity. This is called internal radiotherapy or brachytherapy. In this treatment, the radiation dose is concentrated in a small area and the patient stays in the hospital for a few hours or days.
Radiotherapy may be used alone or in combination with chemotherapy drugs or surgery. Like all forms of cancer treatment, radiotherapy can have side effects, including temporary or permanent loss of hair in the area being treated, skin irritation, temporary change in skin colour in the treated area and fatigue.
Medical imaging is an increasingly important component of clinical quality assurance for radiotherapy. With better knowledge about the size, shape and location of cancer, it is impossible to more accurately deliver radiotherapy to the tumour volume. Moreover the ability to combine images from different imaging modalities had provided new benefits to patients receiving radiotherapy because the various tools provide complementary information.




Ten commandments
Priya Lenin
S1S2-EEE

The most damaging one-letter word: I: Avoid it
The most satisfying two-letter word: WE: Use it
The most poisonous 3-letter word: EGO: kill it
The most used 4-letter word: LOVE: Value it
The most pleasing 5-letter word: SMILE: Keep it
The fastest spreading 6-letter word: RUMOUR:Ignore it
The most available 7-letter word: SUCCESS: Achieve it
The most nefarious 8-letter word: JEALOUSY: Distance it
The most powerful 9-letter word: KNOWLEDGE: Acquire it
The most essential 10-letter word: CONFIDENCE: Trust it



Power Projects in Kerala
Indu.J.R
Cibumol.B.Babu
S6 EEE


Ø Kerala’s first hydroelectric power project is at Pallivasal (1906)
Ø The first power plant of unified Kerala is the Maniyar project of Karborundum Universal Company.
Ø The first city in Kerala to start power distribution is Thiruvananthapuram (1929).
Ø The first therm1al power station of Kerala is the Kayamkulam thermal power plant, which was erected (1999).
Ø The first tidal power project of Kerala is the Vizhinjam Power Project (1991).
Ø The first wind energy power project of Kerala is the Kottamala project at Palakkad.
Ø The first diesel power station of Kerala is the Brahmapuram power plant.

Power Plant Capacities
Projects
Capacity (MW)
Idukki
780
Sabarigiri
300
Lower Periyar
180
Idamalayar
75
Kuttyadi
75
Sholayar
54
Kakkad
50
Chenkulam
48
Neryamangalam
45
Pallivasal
37.5
Peringalkkoothu
32
Panniyar
30
Koothunkal
20
Peringalkkuthu
(Idathukara)
16
Kallada
15
Maniyar
12
Peppara
03
The Idukki Power Project








In the heart of the District lies the 'IDUKKI DAM' - Asia's biggest Arch Dam of 555 feet height proudly standing between the two mountains - 'Kuravanmala' (839 meters) and 'Kurathimala' (925 meters). This prestigious project of our nation is situated in Idukki District and its underground Power House is located at Moolamattom, which is about 19 kms from Thodupuzha. Idukki Dam is 43 kms away from Moolamattam. The possibility of hydroelectric development at Idukki was first conceived in 1919. As per history Shri Kolumban, the head of 'Araya' race during 1922 showed the way, to the Malankara Estate Superintendent and his friend Thomas, who were on hunting spree in the forest, the spot of present Arch Dam. He told them of the legend of Kuravan and Kurathi Hills. The mind of Thomas was stirred by the sight of water flow between the mountains and his idea made the dream true of Idukki Arch Dam. Sri. W.J.John of Malankara Estate submitted a report to the Government of Travancore in 1932 on the possiability of constructing a dam at Idukki for Power Generation.
The construction of this Dam commenced on 30 April 1969. Storage of water in idukki reservoir commenced in February 1973. The inauguration of trial run of the first machine was celebrated on 4th October 1975. Commercial operation of the Power Station was commissioned on 12 February 1976 by the then Hon. Prime Minister Smt. Indira Gandhi.
Construction of this Arch Dam and two other dams at Cheruthony and Kulamavu has created an artificial lake of 60 sq. kms. Width and the water stored, is utilised for production of electricity at the unique Moolamattom Power house, which is located inside the rocky caves.

The Project harnesses a major portion of the power potential of Periyar, the largest river in Kerala State, by the creation of a reservoir of 2,000 M.cum (2 Billion Tonnes) capacity, diversion of waters thus impounded through a water conductor system consisting of a power tunnel and two underground pressure shafts to an underground power house situated in Muvattupuzha Valley. The installed capacity of the Power House is 780MW consisting of 6 Units of 180 MW each. The regulated water of Periyar falls through a drop of about 669.2 metres (2195 feet) while generating power in the underground powerhouse.



THE INTERPLANETARY INTERNET
Narayana Kumar S
S1S2, EEE


Over the next several decades as we embark on the next stage of internet’s spread in to our solar system, scientists will need to manipulate sophisticated experimental instruments on space stations and exchange vast stream of data with colleagues living on the moon and eventually Mars. The network that NASA will soon build could very well be the one over which scientists workout startling Martian geology, oceanic conditions under the ice of Jupiter’s frigid moon Europe or the turbulent cloud cover of Venus. It may well be the way a home-sick space explorer sends e-mail back house.
If there were network links to remote probes, scientists could dial into them as easily as they check the latest headlines. All the information generated aboard these vehicles and habitats from humdrum experiments growing crystals in zero gravity to data showing the existence of ancient microbe fossils could come in via, a single network extending through vacuum of space-not just from NASA, but from the European space agency, China’s National Space Administration and other organisations as well. So as we move from space-discovery to exploration, and perhaps even extra-terrestrial settlements, space engineers have begun to radically rethink how mission could best communicate with Earth’s far flung emissaries.
One team of very smart researchers most of them working at the Goddard space flight center in Green belt is testing ways to use the basic networking protocols that run the internet. That would space scientist use of all the tools they use on earth today like web browsers, file transfer software and so on. Using off- the shelf hardware as well as reusing existing earthbound software, would save money and development time.
As enthusiastic these researches are, another group with in NASA has concluded that using Internet protocols in space-at least in deep space-will never work. Like the Goddard group, this company has some very smart people on it side, including surprisingly enough Vinton.G.Lerf who helped to write internet protocols, still used by billions of computers and other devices on internet. According to Lerf and these other NASA researchers, Internet-style chatting with a shuttle 600 kms. Away may be easy enough, but wirelessly conversing with, say, Mars-orbiting craft 200 million kms. Away is on essentially impossible challenge.
Once made, a protocol decision may be lifetime longer than a Pluto’s year. The current Internet protocols are based on principles Lerf sketched out on the history of Internet. NASA has about a year to make network architecture choice that could bind the solar system for decades to come.

VOL 2

TO BE PROFESSIONAL

PROFESSIONAL EDUCATION HAS BECOME THE MOST SOUGHT IN THE DAYS . BUT VERY OFTEN PEOPLE TEND TO IGNORE THE BASIS REQUIREMENTS OF A PROFESSIONAL CARRER .THIS NOTE IS INTENDED TO THROW SOME LIGHT ON THE CHARACTERISTIC TRAITS AND RESPONSIBILITIES OF A TRUE PROFESSIONAL.

WHO IS PROFESSIONAL?

IN A GENERAL SENSE , THE PROFESSIONAL IS REQUIRED TO UNDERGO A SPECILALISED TRAINING PROGRAMME OR EDUCATION FOR BECOMING A PROFESSIONAL .THE TRAINING OR EDUCATION OF A PROFESSIONAL IS MORE INTENSIVE THAN THAT OF A NON PROFESSIONAL.

PROFESSIONALS ARE DEDICATED TO THEIR PROFESSION AND THE PRIMARY OBJECTIVE IS TO SERVE THE HUMANITY.

BEHAVIOUR OF PROFESSIONALS

PROFESSIONALS HAVE TO SET EXAMPLES FOR THEIR BEHAVIOUR IN THE SOCIETY AS PERFECT HUMAN BEINGS .

HONESTY AND INTEGRITY

THESE ARE EXPECTED CHARACTERISTICS OF EVERY HUMAN BEING ,BUT FOR A PROFESIONAL ,IT IS A MUST . A PROFESSIONAL HAS TO BE HONEST AND HONORABLE IN HIS DEEDS AND HONOUR BRINGS HONOUR AS REWARD.

RESPONSIBILITY AND ACCOUNTABILITY

IT IS NATURAL THAT A PROFESSIONAL IS RESPONSIBLE FOR HIS ACTINOS AND BEHAVIOUR.ACCOUNTABILITY IS ASSOCIATED WITH RESPONSIBILITY .A PROFESSIONAL SHOULD BE ACCOUNTABLE TO SOCIETY ,TO PUBLIC,TO THE INSTITUTION HE WORKS AD TO HIMSELF.

RESPECT

RESPECT OTHERS IF U WANT OTHERS TO RESPECT YOU .SOME PEOPLE MAY RESPECT YOU BECOZ OF YOUR POSITION AND POWER YOU HAVE .RESPECT YOUR ELDERS EVEN IF THEY ARE IN A LOWER PROFESION.
EXCELLENCE AND SCHOLASTIC

UPDATING THE KNOWLEDGE SHOULD ALSO BE A CONTINUOUS PROCESS ,EVEN IF AFTER GRADUATION OR POST GRADUATION ,KNOWLEDGE SHOULD BE UPGRADED .

LEADERSHIP

A PROFESSIONAL SHOULD BE ABLE TO LEAD .IT IS EASY TO FOLLOW SOME ONE WHO IS LEADING BUT IT IS NOT EASY TO LEAD OTHERS ,BUT IT CAN DONE SUCCESFULLY BY HAVING SOMESKILL ,TENACITY AND INITIATIVE POWER.
THE LEADERS LEAD AND THE FOLLOWERS FOLLOW,BUT THERE IS A GROUP ,THOUGH SMALL WHO WILL DO NEITHER.

CARING ,COMPASSION AND COMMUNICATION

THESE ARE AGAIN ESSENTIAL QUALITIES OF A PROFESSIONAL SHOULD DEVELOP.PROPER COMMUNICATION THUS WILL GO A LONG WAY IN ALLEVIATING THE DISTRESS OF THE PERSON.

THUS A PROFESSIONAL SHOULD ACCEPT THE RESPONSIBILITY IN MAKIING ENGINEERING DECISION CONSISTENT ,WITH THE SAFETY ,HEALTH AND WELFARE OF THE PUBLEC AND TO DISCLOSE PROMPTLY FACTORS THAT MIGHT ENDANGER THE PUBLIC PROMPTLY FACTORS THAT MIGHT ENDANGER THE PUBLIC OR ENVIRONMENT.

VOL 1

Monthly journal of Department of Electrical & Electronics Engineering
Volume1 January 2005
PRINCIPAL’S MESSAGE

I am happy to know that the electrical engineer’s association of PAACET ”ELECTRA” is celebrating its inaugural function today .These type of associations at a college level improve the dissemination of information among all students irrespective of their specialiasation and help in strengthening their knowledge. A link with industries is essential for the academic growth of the college and personal carrier of the students. This can certainly be achieved by conducting carrier oriented courses, seminars in the upcoming fields and co-ordination with research institutions in the country.
Associations of this kind should strive hard to establish the much needed interface among college, industry, research centers. I trust the association would come up with their own technical journal and conduct seminars on topics of special interest by students and eminent personalities in the field. I wish all the members of the association and the office bearers “ALL THE BEST”
Dr YVKS RAO

SECRETARY’S MESSAGE

It is my proud privilege to be given this opportunity to be at the helm of this association.This journal has been released in association with the inauguration of our association ELECTRA. This journal aims at introducing the latest trends and developments in the field of electrical & electronics which will be of immense help to all budding engineers. I thank all those who have worked behind this to make it a reality. It is only a beginning for ACME. I believe that with all of your help and support we can make ACME a success.
ARUN SEKHAR S

ABOUT ELECTRICAL ENGINEERING

Electrical engineering is concerned with the development and utilization of electrical and electronic technology for the benefit of society. It involves the design, development, and implementation of devices, circuits, and systems that are used in electrical power generation and distribution, machine control, communications, computers, and computer-based information processing. It is a very broad field that affects all aspects of modern society, particularly in this age of information processing, communications, and automation.
The rapid evolution of electrical and electronic technology creates constant change in this discipline. This, in turn, requires a solid foundation of science and mathematics, combined with fundamental engineering sciences and electrical engineering design skills, to provide the student with ability to professionally develop and adapt during a lifetime career. The engineering core courses and the required electrical engineering courses provide this foundation of knowledge and engineering skills.
Electrical engineering technical electives provide the student an opportunity to achieve a greater breadth of knowledge and some degree of specialization in selected areas of special interest.

SREEJITH J S

A lamp used at the historic 1879 New Year’s Eve demonstration of the Edison
LIGHT & POWER
Flick a switch and a light goes on. Flick it again and off it goes. Pretty simple. But developing a system that makes power so easily accessible took a lot of people a lot of hard work. It was also one of the most important things to take place in the late 19th century. Finding ways to generate and deliver power changed nearly everything about the way we live and work.
Most people think of Thomas Edison as the inventor of the light bulb, but that isn’t exactly true. Incandescent lighting—where an electrical current causes a filament to glow—had already been invented. The problem was that the light lasted only a few minutes because the filaments burned out. Edison found a way around that. In 1879 he came up with a workable filament that allowed light bulbs to burn much longer.
A light bulb with no electrical source wasn’t much good, however. Edison knew that a system of generating and distributing electrical power was needed and he set about creating one. In 1882, Edison opened the Pearl Street station in New York City. It was the world’s first commercial power plant. Although it was an enormous plant for its day, the station at Pearl Street was able to produce and distribute electricity to only one square mile of lower Manhattan.
Although it was successful, Edison’s system had problems and limitations. It used direct current (DC), which was not ideal for delivering electricity over long distances. Alternating current (AC) was better suited to the job. AC allows high voltage current to be transmitted through power lines and lowered before the customer gets it. But Edison was committed to DC.
A replica of Nikola Tesla's 1888 AC motor..
Others, however, were determined to compete with Edison by using AC. AC worked fine with light bulbs, but it was not yet practical for powering electric motors. So the first step was to develop a good AC motor. Finding a way to produce a rotating magnetic field electrically, Nikola Tesla invented a practical AC motor in 1883. Several years later George Westinghouse bought the patents to the Tesla motor and set up an AC power system. For a while, Westinghouse and Edison were in a fierce competition to see whose system would dominate. The winner was clear after a new AC power plant opened at Niagara Falls in 1895 and was used to light up portions of Buffalo, New York. Its successful use in transmitting large amounts of power to distant places was the deciding factor. Today, the whole world continues to use AC.
The generation of large amounts of electricity and the development of reliable delivery systems changed the world. Once electricity was cheap and reliable, other inventions followed. Availability of electricity led to widespread use of electric appliances, some of which we still use today. In 1908 the vacuum cleaner came on the market. Five years later an appropriate motor (one that didn't need lubrication and was small in size) made the electric refrigerator possible. Washing machines and dishwashers soon came on the scene. In 1935 the clothes dryer was invented. Electricity eventually powered radios, televisions, refrigerators, computers, and countless other devices. Electricity was everywhere and it was changing the way people lived.
Today we use electricity for so many things that we take it for granted and often waste it by leaving lights burning in empty rooms or running appliances when it's not necessary. But engineers around the world are always working hard to find new ways to produce and distribute it.

RUFUS JOSHUA VARUGHESE