Electric Power Industry

The modern electric power industry covers the generation, transmission, distribution, and sale of electric power to the general public and industry. The commercial distribution of electric power started in 1882 when electricity was produced for electric lighting. In the 1880s and 1890s, growing economic and safety concerns lead to the regulation of the industry. What was once an expensive novelty limited to the most densely populated areas, reliable and economical electric power has become an essential aspect for normal operation of all elements of developed economies!

History of Electricity

In early Greece, it was found that the electron (amber), when rubbed, acquired the power of attracting low-density materials. The widespread use of electricity for heat, light, and power depended on the development of mechanical methods of generation. During the 17th and 18th centuries, static electricity was found to be distinct from electric currents. Electricity could be positive or negative as charged bodies repelled or attracted each other, distinguishing conductors from nonconductors.

In 1754, John Canton devised an instrument to measure electricity based on the repulsion of like-charged pith suspended by threads, and this was later standardized and redesigned as the gold leaf electroscope. Benjamin Franklin identiﬁed the electrical discharge principle of lightning. This lead to the invention of the “lightning conductor”. In Italy, Allesandro Volta, a natural scientist, found that electricity was derived when alternate metal plates of silver or copper and zinc contacted each other within a solution. The importance of this discovery was that it provided a source of continuous electric current. The original voltaic energy battery gave a stimulus to the experimental study of electricity. In a matter of months, laboratories produced electric batteries, converting the energy released in chemical reactions.

In 1820, Danish physicist H. C. Oersted described the magnetic ﬁeld surrounding a conductor carrying an electric current. The relationship between the strength of a magnetic ﬁeld and its electric current established that a continuous conductor in a magnetic ﬁeld causes electric currents to ﬂow. From 1834, rotating coil generators were made commercially in London. The earliest generators produced alternating currents. Converting alternating energy into direct electric currents was resolved via a mechanical commutator and rectangular coils that rotated in a magnetic ﬁeld. The maximum voltage in each coil was generated in succession, alleviating the irregularities at a given speed of rotation providing constant voltage.

By 1825, electromagnets were used as an alternative to permanent magnets by the founder of the ﬁrst English electrical journal, William Sturgeon. Electromagnets possessed enough residual magnetism in their iron cores to provide the necessary magnetic ﬁeld to start output from an electric generator. The electric generator became a self-contained machine that needed only to be rotated to produce electrical energy. The application of a steam engine to rotate the armature generated enough electricity to supply arc lamps for lighthouses, bringing large-scale use of electricity a step closer.

Robert Hammond, in December 1881, demonstrated the new electric light in the Sussex town of Brighton in the UK for a trial period. The ensuing success of this installation enabled Hammond to put this venture on both a commercial and legal footing, as a number of shop owners wanted to use the new electric light. Thus the Hammond Electricity Supply Co. was launched.

An armature using a continuous winding of copper wire increased the possibilities of using arc lamps for lighting streets. Arc lamps developed after the discovery that a spark struck between two pieces of carbon creates brilliant light.

Inventors Thomas A. Edison and Sir Joseph Swan developed ﬁlament lamps for domestic use during the 1870s, and an incandescent ﬁlament lamp used an electric current Local electrical generation evolved into large centralized distribution utilities, and surplus electricity was sold to local consumers. In early 1882, Edison opened the world's first steam-powered electricity generating station at Holborn Viaduct in London, where he had entered into an agreement with the City Corporation for a period of three months to provide street lighting. In time he had supplied a number of local consumers with electric light. The method of supply was direct current (DC). Whilst the Godalming and the 1882 Holborn Viaduct Scheme closed after a few years the Brighton Scheme continued on, and supply was in 1887 made available for 24 hours per day. In 1889, the London Electricity Supply Corporation’s power station provided high voltage by operating four 10,000-hp steam engines to fuel 10,000-volt alternators.

The economic advantages of central power stations to generate electricity at high voltages for serving large areas brought new practical and economic problems of distribution and, thus, further innovations. By the end of the 19th century, underground distribution systems of electricity had color-coded cables. Each strand was identiﬁed in this manner, a major consideration given that the electrical network beneath city streets increased in complexity.

By the middle of the 20th century, electricity was seen as a "natural monopoly", only efficient if a restricted number of organizations participated in the market; in some areas, vertically-integrated companies provide all stages from generation to retail, and only governmental supervision regulated the rate of return and cost structure.

Electric Power Industry

Since the 1990s, many regions have broken up the generation and distribution of electric power to provide a more competitive electricity market. While such markets can be abusively manipulated with consequent adverse price and reliability impact to consumers, generally competitive production of electrical energy leads to worthwhile improvements inefficiency. However, transmission and distribution are harder problems since returns on investment are not as easy to find.

It was later on in the year in September 1882 that Edison opened the Pearl Street Power Station in New York City and again it was a DC supply. It was for this reason that the generation was close to or on the consumer's premises as Edison had no means of voltage conversion. The voltage chosen for any electrical system is a compromise. For a given amount of power transmitted, increasing the voltage reduces the current and therefore reduces the required wire thickness. Unfortunately, it also increases the danger from direct contact and increases the required insulation thickness. Furthermore, some load types were difficult or impossible to make work with higher voltages. The overall effect was that Edison's system required power stations to be within a mile of the consumers. While this could work in city centers, it would be unable to economically supply suburbs with power.

Organization of the Electric Power Industry

The electric power industry is commonly split up into four processes. These are electricity generation such as a power station, electric power transmission, electricity distribution, and electricity retailing. In many countries, electric power companies own the whole infrastructure from generating stations to transmission and distribution infrastructure.

Electricity Generation Industry

All forms of electricity generation have positive and negative aspects. Technology will probably eventually declare the most preferred forms, but in a market economy, the options with less overall costs generally will be chosen above other sources. It is not clear yet which form can best meet the necessary energy demands or which process can best solve the demand for electricity. There are indications that renewable energy and distributed generation are becoming more viable in economic terms. A diverse mix of generation sources reduces the risks of electricity price spikes.

Electric Power Transmission Industry

Electric power transmission is the bulk movement of electrical energy from a generating site, such as a power plant, to an electrical substation. The interconnected lines which facilitate this movement are known as a transmission network. This is distinct from the local wiring between high-voltage substations and customers, which is typically referred to as electric power distribution. The combined transmission and distribution network is known as the "power grid" in North America, or just "the grid". In the United Kingdom, India, Malaysia, and New Zealand, the network is known as the National Grid.

Electric power is transmitted on overhead lines like these, and also on underground high-voltage cables

Electric Power Distribution Industry

Electric power distribution is the final stage in the delivery of electric power; it carries electricity from the transmission system to individual consumers. Distribution substations connect to the transmission system and lower the transmission voltage to medium voltage ranging between 2 kV and 35 kV with the use of transformers. Primary distribution lines carry this medium voltage power to distribution transformers located near the customer's premises. Distribution transformers again lower the voltage to the utilization voltage used by lighting, industrial equipment or household appliances.