Generation & Distribution Of Electricity

Electricity is mostly generated by power stations that use fossil fuels (coal, gas, oil) and nuclear facilities that use uranium. Due to environmental and safety concerns, and more recently energy security concerns as the oil supply is dependent on fewer and fewer countries, alternative sources of energy are being explored.
Renewable energy provides 21 percent of the world energy needs, including hydropower (20 percent), solar, wind, geothermal, biomass, and tidal energy (approximately 1 percent but growing). As the renewable energy sector grows, the technologies used are become more efficient and less expensive. Therefore prices are becoming more comparative to electricity from non-renewable sources.

  • Electricity generation: fossil fuels and uranium 
  • Renewable energy is growing

                           This figure illustrates the generation, transmission and distribution of electricity

  • AC generators (“alternators”) generate electricity
    1.  Electricity generated at 9-13 KV
    2.  Power generated from 67.5 to 1000 MW
  • Power stations: generating transformers (GTs) to increase voltage to 132-400 KV
  • Substations: step-down transformers to reduce voltage before distribution
  • Electricity is mostly generated by AC generators called “alternators” in thermal, hydro or nuclear power plants at 50 or 60 cycles per second. 
  • Electricity is typically generated at about 9 to 13 KV at the generator terminal. The power generated by one generator (also termed as UNIT) is in the range of 67.5 MW, 110 MW, 220 MW, and 500 MW, although 1000 MW generators also exist.
  • Higher MW rating of generation capacity is preferred because of less auxiliary power consumption and other operation & maintenance cost. 
  • Electricity must be generated when it is needed since electricity cannot be stored. All power stations have generating transformers (GTs) that increase the voltage to extra high voltages (EHV, e.g. 132 KV, 220 KV, 400 KV) prior to transmission. 
  • Similarly, sub-stations have step-down transformers, which reduce the voltage for distribution to industrial, commercial and residential users through distribution lines. 
  • There is no difference between a transmission line and a distribution line except for the voltage level and power handling capability. Transmission lines operate at EHV and are usually capable of transmitting large quantities of electric energy over great distances. Distribution lines carry limited quantities of power at a lower voltage over shorter distances.

Benefits of high voltage transmission

  • Less voltage drop: good voltage regulation 
  • Less power loss: high transmission efficiency 
  • Smaller conductor: lower costs  

Less voltage drop: Voltage drops in transmission/distribution lines are dependent on the resistance, reactance and length of the line, and the current drawn. For the same quantity of power handled, a higher voltage results in a lower current drawn and lower voltage drop. Benefit is good voltage regulation i.e. the difference between voltages sent and received at small.

Less power loss: the power loss in lines is proportional to the resistance (R) and the square of the current (I), i.e. PLoss = I2R. A higher voltage results in lower currents and therefore lowers power losses. Benefit is high transmission efficiency
Smaller conductor: a higher voltage results in lower currents and therefore a smaller conductor is needed to handle the current. Benefit is less capital and erection cost.

No comments:

Post a Comment


PROJECTS 8086 PIN CONFIGURATION 80X86 PROCESSORS TRANSDUCERS 8086 – ARCHITECTURE Hall-Effect Transducers INTEL 8085 OPTICAL MATERIALS BIPOLAR TRANSISTORS INTEL 8255 Optoelectronic Devices Thermistors thevenin's theorem MAXIMUM MODE CONFIGURATION OF 8086 SYSTEM ASSEMBLY LANGUAGE PROGRAMME OF 80X86 PROCESSORS POWER PLANT ENGINEERING PRIME MOVERS 8279 with 8085 MINIMUM MODE CONFIGURATION OF 8086 SYSTEM MISCELLANEOUS DEVICES MODERN ENGINEERING MATERIALS 8085 Processor- Q and A-1 BASIC CONCEPTS OF FLUID MECHANICS OSCILLATORS 8085 Processor- Q and A-2 Features of 8086 PUMPS AND TURBINES 8031/8051 MICROCONTROLLER Chemfet Transducers DIODES FIRST LAW OF THERMODYNAMICS METHOD OF STATEMENTS 8279 with 8086 HIGH VOLTAGE ENGINEERING OVERVOLATGES AND INSULATION COORDINATION Thermocouples 8251A to 8086 ARCHITECTURE OF 8031/8051 Angle-Beam Transducers DATA TRANSFER INSTRUCTIONS IN 8051/8031 INSTRUCTION SET FOR 8051/8031 INTEL 8279 KEYBOARD AND DISPLAY INTERFACES USING 8279 LOGICAL INSTRUCTIONS FOR 8051/8031 Photonic Transducers TECHNOLOGICAL TIPS THREE POINT STARTER 8257 with 8085 ARITHMETIC INSTRUCTIONS IN 8051/8031 LIGHTNING PHENOMENA Photoelectric Detectors Physical Strain Gage Transducers 8259 PROCESSOR APPLICATIONS OF HALL EFFECT BRANCHING INSTRUCTIONS FOR 8051/8031 CPU OF 8031/8051 Capacitive Transducers DECODER Electromagnetic Transducer Hall voltage INTEL 8051 MICROCONTROLLER INTEL 8251A Insulation Resistance Test PINS AND SIGNALS OF 8031/8051 Physical Transducers Resistive Transducer STARTERS Thermocouple Vacuum Gages USART-INTEL 8251A APPLICATIONs OF 8085 MICROPROCESSOR CAPACITANCE Data Transfer Instructions In 8086 Processors EARTH FAULT RELAY ELECTRIC MOTORS ELECTRICAL AND ELECTRONIC INSTRUMENTS ELECTRICAL BREAKDOWN IN GASES FIELD EFFECT TRANSISTOR (FET) INTEL 8257 IONIZATION AND DECAY PROCESSES Inductive Transducers Microprocessor and Microcontroller OVER CURRENT RELAY OVER CURRENT RELAY TESTING METHODS PhotoConductive Detectors PhotoVoltaic Detectors Registers Of 8051/8031 Microcontroller Testing Methods ADC INTERFACE AMPLIFIERS APPLICATIONS OF 8259 EARTH ELECTRODE RESISTANCE MEASUREMENT TESTING METHODS EARTH FAULT RELAY TESTING METHODS Electricity Ferrodynamic Wattmeter Fiber-Optic Transducers IC TESTER IC TESTER part-2 INTERRUPTS Intravascular imaging transducer LIGHTNING ARRESTERS MEASUREMENT SYSTEM Mechanical imaging transducers Mesh Current-2 Millman's Theorem NEGATIVE FEEDBACK Norton's Polarity Test Potentiometric transducers Ratio Test SERIAL DATA COMMUNICATION SFR OF 8051/8031 SOLIDS AND LIQUIDS Speed Control System 8085 Stepper Motor Control System Winding Resistance Test 20 MVA 6-digits 6-digits 7-segment LEDs 7-segment A-to-D A/D ADC ADVANTAGES OF CORONA ALTERNATOR BY POTIER & ASA METHOD ANALOG TO DIGITAL CONVERTER AUXILIARY TRANSFORMER AUXILIARY TRANSFORMER TESTING AUXILIARY TRANSFORMER TESTING METHODS Analog Devices A–D BERNOULLI’S PRINCIPLE BUS BAR BUS BAR TESTING Basic measuring circuits Bernoulli's Equation Bit Manipulation Instruction Buchholz relay test CORONA POWER LOSS CURRENT TRANSFORMER CURRENT TRANSFORMER TESTING Contact resistance test Current to voltage converter DAC INTERFACE DESCRIBE MULTIPLY-EXCITED Digital Storage Oscilloscope Display Driver Circuit E PROMER ELPLUS NT-111 EPROM AND STATIC RAM EXCITED MAGNETIC FIELD Electrical Machines II- Exp NO.1 Energy Meters FACTORS AFFECTING CORONA FLIP FLOPS Fluid Dynamics and Bernoulli's Equation Fluorescence Chemical Transducers Foil Strain Gages HALL EFFECT HIGH VOLTAGE ENGG HV test HYSTERESIS MOTOR Hall co-efficient Hall voltage and Hall Co-efficient High Voltage Insulator Coating Hot-wire anemometer How to Read a Capacitor? IC TESTER part-1 INSTRUMENT TRANSFORMERS Importance of Hall Effect Insulation resistance check Insulator Coating Knee point Test LEDs LEDs Display Driver LEDs Display Driver Circuit LM35 LOGIC CONTROLLER LPT LPT PORT LPT PORT EXPANDER LPT PORT LPT PORT EXTENDER Life Gone? MAGNETIC FIELD MAGNETIC FIELD SYSTEMS METHOD OF STATEMENT FOR TRANSFORMER STABILITY TEST METHODS OF REDUCING CORONA EFFECT MULTIPLY-EXCITED MULTIPLY-EXCITED MAGNETIC FIELD SYSTEMS Mesh Current Mesh Current-1 Moving Iron Instruments Multiplexing Network Theorems Node Voltage Method On-No Load And On Load Condition PLC PORT EXTENDER POTIER & ASA METHOD POWER TRANSFORMER POWER TRANSFORMER TESTING POWER TRANSFORMER TESTING METHODS PROGRAMMABLE LOGIC PROGRAMMABLE LOGIC CONTROLLER Parallel Port EXPANDER Paschen's law Piezoelectric Wave-Propagation Transducers Potential Transformer RADIO INTERFERENCE RECTIFIERS REGULATION OF ALTERNATOR REGULATION OF THREE PHASE ALTERNATOR Read a Capacitor SINGLY-EXCITED SOLIDS AND LIQUIDS Classical gas laws Secondary effects Semiconductor strain gages Speaker Driver Strain Gages Streamer theory Superposition Superposition theorem Swinburne’s Test TMOD TRANSFORMER TESTING METHODS Tape Recorder Three-Phase Wattmeter Transformer Tap Changer Transformer Testing Vector group test Virus Activity Voltage Insulator Coating Voltage To Frequency Converter Voltage to current converter What is analog-to-digital conversion Windows work for Nokia capacitor labels excitation current test magnetic balance voltage to frequency converter wiki electronic frequency converter testing voltage with a multimeter 50 hz voltages voltmeter

Search More Posts