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ModbusFrom Wikipedia, the free encyclopedia

Modbusis a serialcommunications protocoloriginally published by Modicon(now SchneiderElectric) in 1! for use with its programmable logic controllers("#$s)% Simple and robust, it hassince become ade factostandardcommunication protocol, and it is now a commonly a&ailablemeans of connecting industrial electronicde&ices%'1he main reasons for the use of Modbus in theindustrial en&ironment are*

de&eloped with industrial applications in mind

openly published and royalty+free

easy to deploy and maintain

mo&es raw bits or words without placing many restrictions on&endors

Modbus enables communication among many de&ices connected to the same network, for eamplea system that measures temperature and humidity and communicates the results to acomputer%Modbus is often used to connect a super&isory computer with aremote terminal unit(-.)in super&isory control and data ac/uisition(S$00) systems% Many of the data types are namedfrom its use in dri&ing relays* a single+bit physical output is called a coil, and a single+bit physical

input is called a discrete inputor a contact%he de&elopment and update of Modbus protocols has been managed by the Modbus2rgani3ation'4since 0pril 4556, when Schneider Electric transferred rights to that organi3ation% '7heModbus 2rgani3ation is an association of users and suppliers of Modbus compliant de&ices thatseeks to dri&e the adoption and e&olution of Modbus% '6

Contents

'hide

1"rotocol &ersions

4$ommunication and de&ices

7Frame format

6Supported function codes

8Format of data of re/uests and responses for main function codes

o 8%1Function code 1 (read coils) and function code 4 (read discreteinputs)

o 8%4Function code 8 (force9write single coil)

o 8%7Function code 18 (force9write multiple coils)
https://en.wikipedia.org/wiki/Communications_protocolhttps://en.wikipedia.org/wiki/Communications_protocolhttps://en.wikipedia.org/wiki/Modiconhttps://en.wikipedia.org/wiki/Schneider_Electrichttps://en.wikipedia.org/wiki/Schneider_Electrichttps://en.wikipedia.org/wiki/Programmable_logic_controllerhttps://en.wikipedia.org/wiki/De_factohttps://en.wikipedia.org/wiki/De_factohttps://en.wikipedia.org/wiki/Standardizationhttps://en.wikipedia.org/wiki/Electronicshttps://en.wikipedia.org/wiki/Modbus#cite_note-Drury2009-1https://en.wikipedia.org/wiki/Computerhttps://en.wikipedia.org/wiki/Computerhttps://en.wikipedia.org/wiki/Computerhttps://en.wikipedia.org/wiki/Remote_terminal_unithttps://en.wikipedia.org/wiki/Remote_terminal_unithttps://en.wikipedia.org/wiki/Remote_terminal_unithttps://en.wikipedia.org/wiki/Supervisory_control_and_data_acquisitionhttps://en.wikipedia.org/wiki/SCADAhttps://en.wikipedia.org/wiki/Modbus#cite_note-Modbus_home-2https://en.wikipedia.org/wiki/Modbus#cite_note-3https://en.wikipedia.org/wiki/Modbus#cite_note-4https://en.wikipedia.org/wiki/Modbushttps://en.wikipedia.org/wiki/Modbus#Protocol_versionshttps://en.wikipedia.org/wiki/Modbus#Communication_and_deviceshttps://en.wikipedia.org/wiki/Modbus#Frame_formathttps://en.wikipedia.org/wiki/Modbus#Supported_function_codeshttps://en.wikipedia.org/wiki/Modbus#Format_of_data_of_requests_and_responses_for_main_function_codeshttps://en.wikipedia.org/wiki/Modbus#Function_code_1_.28read_coils.29_and_function_code_2_.28read_discrete_inputs.29https://en.wikipedia.org/wiki/Modbus#Function_code_1_.28read_coils.29_and_function_code_2_.28read_discrete_inputs.29https://en.wikipedia.org/wiki/Modbus#Function_code_5_.28force.2Fwrite_single_coil.29https://en.wikipedia.org/wiki/Modbus#Function_code_15_.28force.2Fwrite_multiple_coils.29https://en.wikipedia.org/wiki/Modiconhttps://en.wikipedia.org/wiki/Schneider_Electrichttps://en.wikipedia.org/wiki/Schneider_Electrichttps://en.wikipedia.org/wiki/Programmable_logic_controllerhttps://en.wikipedia.org/wiki/De_factohttps://en.wikipedia.org/wiki/Standardizationhttps://en.wikipedia.org/wiki/Electronicshttps://en.wikipedia.org/wiki/Modbus#cite_note-Drury2009-1https://en.wikipedia.org/wiki/Computerhttps://en.wikipedia.org/wiki/Remote_terminal_unithttps://en.wikipedia.org/wiki/Supervisory_control_and_data_acquisitionhttps://en.wikipedia.org/wiki/SCADAhttps://en.wikipedia.org/wiki/Modbus#cite_note-Modbus_home-2https://en.wikipedia.org/wiki/Modbus#cite_note-3https://en.wikipedia.org/wiki/Modbus#cite_note-4https://en.wikipedia.org/wiki/Modbushttps://en.wikipedia.org/wiki/Modbus#Protocol_versionshttps://en.wikipedia.org/wiki/Modbus#Communication_and_deviceshttps://en.wikipedia.org/wiki/Modbus#Frame_formathttps://en.wikipedia.org/wiki/Modbus#Supported_function_codeshttps://en.wikipedia.org/wiki/Modbus#Format_of_data_of_requests_and_responses_for_main_function_codeshttps://en.wikipedia.org/wiki/Modbus#Function_code_1_.28read_coils.29_and_function_code_2_.28read_discrete_inputs.29https://en.wikipedia.org/wiki/Modbus#Function_code_1_.28read_coils.29_and_function_code_2_.28read_discrete_inputs.29https://en.wikipedia.org/wiki/Modbus#Function_code_5_.28force.2Fwrite_single_coil.29https://en.wikipedia.org/wiki/Modbus#Function_code_15_.28force.2Fwrite_multiple_coils.29https://en.wikipedia.org/wiki/Communications_protocol


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o 8%6Function code 6 (read input registers) and function code 7 (readholding registers)

o 8%8Function code : (preset9write single holding register)

o 8%:Function code 1: (preset9write multiple holding registers)

o 8%!Eception responses

o 8%;Main Modbus eception codes

:$oil, discrete input, input register, holding register numbers and addresses

o :%1mplementations

;#imitations

rade group

15Modbus "lus

11-eferences

14Eternal links

Protocol versions'edit

?ersions of the Modbus protocol eist forserial portand for Ethernetand other protocols that supportthe>nternet protocol suite% here are many &ariants of Modbus protocols*

Modbus RTU@ his is used in serial communication A makes useof a compact, binary representation of the data for protocolcommunication% he -. format follows the commands9data witha cyclic redundancy checkchecksum as an error check mechanismto ensure the reliability of data% Modbus -. is the most commonimplementation a&ailable for Modbus% 0 Modbus -. messagemust be transmitted continuously without inter+character hesitations%Modbus messages are framed (separated) by idle (silent) periods%

ModbusASCII@ his is used in serial communication A makes use

of 0S$>> characters for protocol communication% he 0S$>> formatuses a longitudinal redundancy checkchecksum% Modbus 0S$>>messages are framed by leading colon (B*B) and trailing newline($-9#F)%

ModbusTCP/IPor Modbus TCP@ his is a Modbus &ariant usedfor communications o&er $"9>" networks, connecting o&er port854%'8>t does not re/uire a checksum calculation as lower layersalready pro&ide checksum protection%

Modbus over TCP/IPor Modbus over TCP or Modbus RTU/IP@his is a Modbus &ariant that differs from Modbus $" in that a

checksum is included in the payload as with Modbus -.%':
https://en.wikipedia.org/wiki/Modbus#Function_code_4_.28read_input_registers.29_and_function_code_3_.28read_holding_registers.29https://en.wikipedia.org/wiki/Modbus#Function_code_4_.28read_input_registers.29_and_function_code_3_.28read_holding_registers.29https://en.wikipedia.org/wiki/Modbus#Function_code_6_.28preset.2Fwrite_single_holding_register.29https://en.wikipedia.org/wiki/Modbus#Function_code_16_.28preset.2Fwrite_multiple_holding_registers.29https://en.wikipedia.org/wiki/Modbus#Exception_responseshttps://en.wikipedia.org/wiki/Modbus#Main_Modbus_exception_codeshttps://en.wikipedia.org/wiki/Modbus#Coil.2C_discrete_input.2C_input_register.2C_holding_register_numbers_and_addresseshttps://en.wikipedia.org/wiki/Modbus#JBUS_mappinghttps://en.wikipedia.org/wiki/Modbus#Implementationshttps://en.wikipedia.org/wiki/Modbus#Limitationshttps://en.wikipedia.org/wiki/Modbus#Trade_grouphttps://en.wikipedia.org/wiki/Modbus#Modbus_Plushttps://en.wikipedia.org/wiki/Modbus#Referenceshttps://en.wikipedia.org/wiki/Modbus#External_linkshttps://en.wikipedia.org/w/index.php?title=Modbus&action=edit&section=1https://en.wikipedia.org/w/index.php?title=Modbus&action=edit&section=1https://en.wikipedia.org/wiki/Serial_porthttps://en.wikipedia.org/wiki/Serial_porthttps://en.wikipedia.org/wiki/Ethernethttps://en.wikipedia.org/wiki/Internet_protocol_suitehttps://en.wikipedia.org/wiki/Internet_protocol_suitehttps://en.wikipedia.org/wiki/Cyclic_redundancy_checkhttps://en.wikipedia.org/wiki/ASCIIhttps://en.wikipedia.org/wiki/ASCIIhttps://en.wikipedia.org/wiki/Longitudinal_redundancy_checkhttps://en.wikipedia.org/wiki/TCP/IPhttps://en.wikipedia.org/wiki/TCP/IPhttps://en.wikipedia.org/wiki/TCP/IPhttps://en.wikipedia.org/wiki/Modbus#cite_note-modbustcp-5https://en.wikipedia.org/wiki/TCP/IPhttps://en.wikipedia.org/wiki/Modbus#cite_note-6https://en.wikipedia.org/wiki/Modbus#Function_code_4_.28read_input_registers.29_and_function_code_3_.28read_holding_registers.29https://en.wikipedia.org/wiki/Modbus#Function_code_4_.28read_input_registers.29_and_function_code_3_.28read_holding_registers.29https://en.wikipedia.org/wiki/Modbus#Function_code_6_.28preset.2Fwrite_single_holding_register.29https://en.wikipedia.org/wiki/Modbus#Function_code_16_.28preset.2Fwrite_multiple_holding_registers.29https://en.wikipedia.org/wiki/Modbus#Exception_responseshttps://en.wikipedia.org/wiki/Modbus#Main_Modbus_exception_codeshttps://en.wikipedia.org/wiki/Modbus#Coil.2C_discrete_input.2C_input_register.2C_holding_register_numbers_and_addresseshttps://en.wikipedia.org/wiki/Modbus#JBUS_mappinghttps://en.wikipedia.org/wiki/Modbus#Implementationshttps://en.wikipedia.org/wiki/Modbus#Limitationshttps://en.wikipedia.org/wiki/Modbus#Trade_grouphttps://en.wikipedia.org/wiki/Modbus#Modbus_Plushttps://en.wikipedia.org/wiki/Modbus#Referenceshttps://en.wikipedia.org/wiki/Modbus#External_linkshttps://en.wikipedia.org/w/index.php?title=Modbus&action=edit&section=1https://en.wikipedia.org/wiki/Serial_porthttps://en.wikipedia.org/wiki/Ethernethttps://en.wikipedia.org/wiki/Internet_protocol_suitehttps://en.wikipedia.org/wiki/Cyclic_redundancy_checkhttps://en.wikipedia.org/wiki/ASCIIhttps://en.wikipedia.org/wiki/Longitudinal_redundancy_checkhttps://en.wikipedia.org/wiki/TCP/IPhttps://en.wikipedia.org/wiki/Modbus#cite_note-modbustcp-5https://en.wikipedia.org/wiki/TCP/IPhttps://en.wikipedia.org/wiki/Modbus#cite_note-6


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Modbus over UDP@ Some ha&e eperimented with using Modbuso&er ." on >" networks, which remo&es the o&erheads re/uiredfor$"'!

Modbus Plus (Modbus+, M+ or MP!Modbuso&erFieldbus(ModbusC or M=C), also eists, but remainsproprietary to Schneider Electric% re/uires a dedicated co+processorto handle fast D#$+like token rotation% >t uses twisted pair at 1

Mbit9s and includes transformer isolation at each node, whichmakes it transition9edge triggered instead of &oltage9le&el triggered%Special interfaces are re/uired to connect Modbus "lus to acomputer, typically a card made for the >S0 (S0;8), "$> or "$M$>0bus%

ModbusP"M"#+ his &ariant is an etension of standard Modbuswith support for historical and flow data% >t was designed for processcontrol and ne&er gained widespread adoption';

"nronModbus+ his &ariant is an etension of standard Modbuswith support for 74 bit >nteger and Floating "oint &ariables, and

historical and flow data% ata types are mapped using standardaddresses%'he historical data is used to meet an0merican"etroleum >nstitute(0">) industry standard for how data should bestored'15

ata model and function calls are identical for the first 6 &ariants of protocols only the encapsulationis different% Dowe&er the &ariants are not interoperable as the frame formats are different%

Communication and devices'edit

Each de&ice intended to communicate using Modbus is gi&en a uni/ue address% >n serial and M=Cnetworks, only the node assigned as the Master may initiate a command% 2n Ethernet, any de&icecan send out a Modbus command, although usually only one master de&ice does so% 0 Modbus

command contains the Modbus address of the de&ice it is intended for (1 to 46!)% 2nly the intendedde&ice will act on the command, e&en though other de&ices might recei&e it (an eception is specificbroadcastable commands sent to node 5 which are acted on but not acknowledged)% 0ll Modbuscommands contain checksum information, to allow the recipient to detect transmission errors% hebasic Modbus commands can instruct an -. to change the &alue in one of its registers, control orread an >92 port, and command the de&ice to send back one or more &alues contained in itsregisters%

here are many modems and gateways that support Modbus, as it is a &ery simple protocol andoften copied% Some of them were specifically designed for this protocol% ifferent implementationsuse wireline, wireless communication, such as in the>SM band,and e&en short messageser&ice(SMS) or eneral "acket -adio Ser&ice("-S)% 2ne of the more common designs ofwireless networks makes use of Mesh networking% ypical problems that designers ha&e too&ercome include high latency and timing issues%

Frame format'edit

0 Modbus frame is composed of an 0pplication ata .nit (0.) which encloses a "rotocol ata .nit(".)*'11

0. G 0ddress C ". C Error check

". G Function code C ata

0ll Modbus &ariants choose one of the following frame formats%'1

Modbus RTUframe format (primarily used on 8-bit asynchronous lines likeEIA-48!
https://en.wikipedia.org/wiki/User_Datagram_Protocolhttps://en.wikipedia.org/wiki/Transmission_Control_Protocolhttps://en.wikipedia.org/wiki/Transmission_Control_Protocolhttps://en.wikipedia.org/wiki/Transmission_Control_Protocolhttps://en.wikipedia.org/wiki/Modbus#cite_note-7https://en.wikipedia.org/wiki/Fieldbushttps://en.wikipedia.org/wiki/Fieldbushttps://en.wikipedia.org/wiki/Fieldbushttps://en.wikipedia.org/wiki/Schneider_Electrichttps://en.wikipedia.org/wiki/High-Level_Data_Link_Controlhttps://en.wikipedia.org/wiki/PEMEXhttps://en.wikipedia.org/wiki/PEMEXhttps://en.wikipedia.org/wiki/Modbus#cite_note-8https://en.wikipedia.org/wiki/Modbus#cite_note-8https://en.wikipedia.org/wiki/Enronhttps://en.wikipedia.org/wiki/Enronhttps://en.wikipedia.org/wiki/Modbus#cite_note-9https://en.wikipedia.org/wiki/Modbus#cite_note-9https://en.wikipedia.org/wiki/American_Petroleum_Institutehttps://en.wikipedia.org/wiki/American_Petroleum_Institutehttps://en.wikipedia.org/wiki/American_Petroleum_Institutehttps://en.wikipedia.org/wiki/Modbus#cite_note-10https://en.wikipedia.org/w/index.php?title=Modbus&action=edit&section=2https://en.wikipedia.org/wiki/ISM_bandhttps://en.wikipedia.org/wiki/ISM_bandhttps://en.wikipedia.org/wiki/ISM_bandhttps://en.wikipedia.org/wiki/Short_message_servicehttps://en.wikipedia.org/wiki/Short_message_servicehttps://en.wikipedia.org/wiki/Short_message_servicehttps://en.wikipedia.org/wiki/General_Packet_Radio_Servicehttps://en.wikipedia.org/wiki/Mesh_networkinghttps://en.wikipedia.org/w/index.php?title=Modbus&action=edit&section=3https://en.wikipedia.org/wiki/Modbus#cite_note-11https://en.wikipedia.org/wiki/Modbus#cite_note-Drury2009-1https://en.wikipedia.org/wiki/Remote_Terminal_Unithttps://en.wikipedia.org/wiki/EIA-485https://en.wikipedia.org/wiki/EIA-485https://en.wikipedia.org/wiki/User_Datagram_Protocolhttps://en.wikipedia.org/wiki/Transmission_Control_Protocolhttps://en.wikipedia.org/wiki/Modbus#cite_note-7https://en.wikipedia.org/wiki/Fieldbushttps://en.wikipedia.org/wiki/Schneider_Electrichttps://en.wikipedia.org/wiki/High-Level_Data_Link_Controlhttps://en.wikipedia.org/wiki/PEMEXhttps://en.wikipedia.org/wiki/Modbus#cite_note-8https://en.wikipedia.org/wiki/Enronhttps://en.wikipedia.org/wiki/Modbus#cite_note-9https://en.wikipedia.org/wiki/American_Petroleum_Institutehttps://en.wikipedia.org/wiki/American_Petroleum_Institutehttps://en.wikipedia.org/wiki/Modbus#cite_note-10https://en.wikipedia.org/w/index.php?title=Modbus&action=edit&section=2https://en.wikipedia.org/wiki/ISM_bandhttps://en.wikipedia.org/wiki/Short_message_servicehttps://en.wikipedia.org/wiki/Short_message_servicehttps://en.wikipedia.org/wiki/General_Packet_Radio_Servicehttps://en.wikipedia.org/wiki/Mesh_networkinghttps://en.wikipedia.org/w/index.php?title=Modbus&action=edit&section=3https://en.wikipedia.org/wiki/Modbus#cite_note-11https://en.wikipedia.org/wiki/Modbus#cite_note-Drury2009-1https://en.wikipedia.org/wiki/Remote_Terminal_Unithttps://en.wikipedia.org/wiki/EIA-485


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"ame #en$th (bits! %unction

&tart 28 At least 3 12character times of silence (mark condition)

Address 8 Station address

%unction 8 Indicates the function code; e.g., read coilsholding registers

'ata n ! 8 "ata # length $ill %e filled de&ending on the message t'&e

R 1 %its 'clic *edundanc' heck

End 28 At least 3 12character times of silence %et$een frames

Hote about the $-$*

"olynomial* 1:C 18C 4C 1 ($-$+1:+0HS> also known as $-$+1:+>=M, normal headecimal algebraic polynomial being 8005 and

re&ersed A001 )

>nitial &alue* :8,878

Eample of frame in headecimal* 01 04 02 FF FF B8 80 ($-$+

1:+0HS> calculation from 01 to FF gi&es 80B8 which istransmitted leastsignificant byte first)

Modbus A&II frame format (primarily used on )- or 8-bit asynchronous serial lines!

"ame #en$th (bytes! %unction

&tart 1 Starts $ith colon : (ASII he+ alue is 0x3a )

Address 2 Station address

%unction 2 Indicates the function codes like read coils in&uts

'ata n + 2 "ata # length $ill %e filled de&ending on the message t'&e

#R 2 hecksum(-ongitudinal redundanc' check)

End 2 arriage return line feed (*-/) &air (ASIIalues of 0+0d 0+0a)

0ddress, function, data, and #-$ are all capital headecimal readable pairs of charactersrepresenting ;+bit &alues (5+488)% For eample, 144 (!1:C15) will be represented as 7A %#-$ is calculated as the sum of ;+bit &alues, negated (twoBs complement) and encoded as an ;+bit&alue% Eample* if address, function, and data encode as 46!, 7, 1, 17!, 5, and 15, their sum is

61:% woBs complement (+61:) trimmed to ;+bit is : (e%g% 48:4+61:) which will be representedas 60 in headecimal% Dence the following frame :F7031389000A60
https://en.wikipedia.org/wiki/Cyclic_Redundancy_Checkhttps://en.wikipedia.org/wiki/Cyclic_redundancy_checkhttps://en.wikipedia.org/wiki/Bytehttps://en.wikipedia.org/wiki/Checksumhttps://en.wikipedia.org/wiki/Checksumhttps://en.wikipedia.org/wiki/Longitudinal_redundancy_checkhttps://en.wikipedia.org/wiki/Longitudinal_redundancy_checkhttps://en.wikipedia.org/wiki/ASCIIhttps://en.wikipedia.org/wiki/ASCIIhttps://en.wikipedia.org/wiki/Two's_complementhttps://en.wikipedia.org/wiki/Cyclic_Redundancy_Checkhttps://en.wikipedia.org/wiki/Cyclic_redundancy_checkhttps://en.wikipedia.org/wiki/Bytehttps://en.wikipedia.org/wiki/Checksumhttps://en.wikipedia.org/wiki/Longitudinal_redundancy_checkhttps://en.wikipedia.org/wiki/ASCIIhttps://en.wikipedia.org/wiki/Two's_complement


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Modbus T* frame format (primarily used onEthernetnet+orks!

"ame #en$th (bytes! %unction

Transaction identifier 2 /or s'nchroniation %et$een messages of serer client

*rotocol identifier 2 ero for 4od%us56

#en$th field 2 7um%er of remaining %'tes in this frame

Unit identifier 1 Slae address (2 if not used)

%unction code 1 /unction codes as in other ariants

'ata bytes n "ata as res&onse or commands

.nit identifier is used with Modbus9$" de&ices that are composites of se&eral Modbus de&ices, e%g%

on Modbus9$" to Modbus -. gateways% >n such case, the unit identifier tells the Sla&e 0ddress ofthe de&ice behind the gateway% Hati&ely Modbus9$"+capable de&ices usually ignore the .nit>dentifier%

he byte order for &alues in Modbus data frames is =ig+Endian(MS=, Most Significant =yte of a&alue recei&ed first)%

Supported function codes'edit

he &arious reading, writing and other operations are categorised as follows% '14he most primiti&ereads and writes are shown in bold% 0 number of sources use alternati&e terminology, foreample $orce Sin%le Coilwhere the standard uses &rite Sin%le Coil%'17

"rominent entities within a Modbus sla&e are*

$oils* readable and writable, 1 bit (off9on)

iscrete >nputs* readable, 1 bit (off9on)

>nput -egisters* readable, 1: bits (5 to :8,878), essentiallymeasurements and statuses

Dolding -egisters* readable and writable, 1: bits (5 to :8,878),essentially configuration &alues

Modbus function codes

%unction type %unction name%unction

code

"ataAccess

9it access 6h'sical "iscrete In&uts Read 'iscrete Inputs 2

Internal 9its or 6h'sical oils Read oils 1
https://en.wikipedia.org/wiki/Ethernethttps://en.wikipedia.org/wiki/Ethernethttps://en.wikipedia.org/wiki/Ethernethttps://en.wikipedia.org/wiki/Endiannesshttps://en.wikipedia.org/wiki/Endiannesshttps://en.wikipedia.org/w/index.php?title=Modbus&action=edit&section=4https://en.wikipedia.org/wiki/Modbus#cite_note-12https://en.wikipedia.org/wiki/Modbus#cite_note-13https://en.wikipedia.org/wiki/Ethernethttps://en.wikipedia.org/wiki/Endiannesshttps://en.wikipedia.org/w/index.php?title=Modbus&action=edit&section=4https://en.wikipedia.org/wiki/Modbus#cite_note-12https://en.wikipedia.org/wiki/Modbus#cite_note-13


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,rite &in$le oil

,rite Multiple oils 1

1:%it

access

6h'sical In&ut *egisters Read Input Re$isters

Internal *egisters or 6h'sical

ueue 2

/ile *ecord Access

*ead /ile *ecord 20

=rite /ile *ecord 21

"iagnostics *ead ?+ce&tion Status @

"iagnostic 8

et om ?ent ounter 11

et om ?ent -og 12

*e&ort Slae I" 1@


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*ead "eice Identification 3

f number of coils9discrete inputs is not a multiple of ;, most significant bit(s) of last byte will bestuffed with 3eros%For eample, if ele&en coils are re/uested, two bytes of &alues are needed% Suppose states of thosesuccessi&e coils are on, off, on, off, off, on, on, on, off, on, on , then data part of the response willbe 02E506 in headecimal%

Function code 5 (force/write single coil)'edit

Request*

0ddress of coil (1:+bit)

?alue to force9write* 5 for off and :8,4;5 (FF55 in headecimal) foron

Normal response* same as re/uest%Function code 15 (force/write multiple coils)'edit

Request*

0ddress of first coil to force9write (1:+bit)

Humber of coils to force9write (1:+bit)

Humber of bytes of coil &alues to follow (;+bit)

$oil &alues (; coil &alues per byte)
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?alue of each coil is binary (5 for off, 1 for on)% First re/uested coil is stored as least significant bit offirst byte in re/uest%>f number of coils is not a multiple of ;, most significant bit(s) of last byte should be stuffed with3eros% See eample for function codes 1 and 4%

Normal response*

0ddress of first coil (1:+bit)

number of coils (1:+bit)

Function code (read input registers) and function code ! (read "oldingregisters)'edit

Request*

0ddress of first register to read (1:+bit)

Humber of registers to read (1:+bit)

Normal response*

Humber of bytes of register &alues to follow (;+bit)

-egister &alues (1: bits per register)

=ecause the number of bytes for register &alues is ;+bit wide, only 14; registers can be read at once%

Function code # (preset/write single "olding register)'edit

Request*

0ddress of holding register to preset9write (1:+bit)

Hew &alue of the holding register (1:+bit)

Normal response* same as re/uest%

Function code 1# (preset/write multiple "olding registers)'edit

Request*

0ddress of first holding register to preset9write (1:+bit)

Humber of holding registers to preset9write (1:+bit)

Humber of bytes of register &alues to follow (;+bit)

Hew &alues of holding registers (1: bits per register)

=ecause the number of bytes for register &alues is ;+bit wide, only 14; holding registers can bepreset9written at once%

Normal response*

0ddress of first preset9written holding register (1:+bit)

number of preset9written holding registers (1:+bit)

$%ception responses'edit
https://en.wikipedia.org/w/index.php?title=Modbus&action=edit&section=9https://en.wikipedia.org/w/index.php?title=Modbus&action=edit&section=10https://en.wikipedia.org/w/index.php?title=Modbus&action=edit&section=11https://en.wikipedia.org/w/index.php?title=Modbus&action=edit&section=12https://en.wikipedia.org/w/index.php?title=Modbus&action=edit&section=9https://en.wikipedia.org/w/index.php?title=Modbus&action=edit&section=10https://en.wikipedia.org/w/index.php?title=Modbus&action=edit&section=11https://en.wikipedia.org/w/index.php?title=Modbus&action=edit&section=12


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For a normal response, sla&e repeats the function code% Should a sla&e want to report an error, it willreply with the re/uested function code plus 14; (7 becomes 171 or 83 in headecimal), and will onlyinclude one byte of data, known as the e'ception code%

Main Modbus e%ception codes'edit

od

eTe.t 'etails

1 Illegal /unction /unction code receied in the Buer' is not recognied or allo$ed %' slae

2 Illegal "ata Address"ata address of some or all the reBuired entities are not allo$ed or do not e+ist

in slae

3 Illegal "ata Calue Calue is not acce&ted %' slae

Slae "eice

/ailure

Dnrecoera%le error occurred $hile slae $as attem&ting to &erform reBuested

action

Ackno$ledge

Slae has acce&ted reBuest and is &rocessing it, %ut a long duration of time is

reBuired. 5his res&onse is returned to &reent a timeout error from occurring

in the master. 4aster can ne+t issue aPoll Program Completemessage todetermine if &rocessing is com&leted

Slae "eice 9us'Slae is engaged in &rocessing a long:duration command. 4aster should retr'

later

@7egatie

Ackno$ledge

Slae cannot &erform the &rogramming functions. 4aster should reBuest

diagnostic or error information from slae

84emor' 6arit'

?rror

Slae detected a &arit' error in memor'. 4aster can retr' the reBuest, %ut

serice ma' %e reBuired on the slae deice

10ate$a' 6ath

Dnaaila%leS&ecialied for 4od%us gate$a's. Indicates a misconfigured gate$a'

11

ate$a' 5arget

"eice /ailed to*es&ond

S&ecialied for 4od%us gate$a's. Sent $hen slae fails to res&ond

Coil, discrete input, input reister, !oldin reister numbers and

addresses'edit
https://en.wikipedia.org/w/index.php?title=Modbus&action=edit&section=13https://en.wikipedia.org/w/index.php?title=Modbus&action=edit&section=13https://en.wikipedia.org/w/index.php?title=Modbus&action=edit&section=14https://en.wikipedia.org/w/index.php?title=Modbus&action=edit&section=14https://en.wikipedia.org/w/index.php?title=Modbus&action=edit&section=13https://en.wikipedia.org/w/index.php?title=Modbus&action=edit&section=14


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Some con&entions go&ern how access to Modbus entities (coils, discrete inputs, input registers,holding registers) are referenced%>t is important to make a distinction between entity nuberand entity address*

Entity nuberscombine entity type and entity location within theirdescription table

Entity addressis the starting address, a 1:+bit &alue in the data part

of the Modbus frame% 0s such its range goes from 5 to :8,878>n the traditional standard, nubersfor those entities start with a digit, followed by a number of fourdigits in range 1 + ,*

coils nubersstart with a &eroand then span from '5551 to '

discrete input nubersstart with a oneand then span from 15551to 1

input register nubersstart with a t"reeand then span from !5551to !

holding register nubersstart with a fourand then spanfrom 5551 to

his translates into addressesbetween 5 and ,; in data frames%For eample, in order to read holding registers starting at nuber65551, corresponding addressinthe data frame will be 5 with a function code of 7 (as seen abo&e)% For holding registers startingat nuber65155, addresswill be % Etc%his limits the number of addressesto , for each entity% 0 de factoreferencing etends this tothe maimum of :8,87:%'16

>t simply consists of adding one digit to the pre&ious list*

coil nubersspan from '55551 to ':887:

discrete input nubersspan from 155551 to 1:887:

input register nubersspan from !55551 to !:887:

holding register nubersspan from 55551 to :887:

When using the etended referencing, all nuberreferences must be eactly si digits% his a&oidsconfusion between coils and other entities% For eample, to know the difference between holdingregister I65551 and coil I65551, if coil I65551 is the target, it must appear as I565551%

*+ mapping'edit

0nother de factoprotocol tightly related with Modbus'18appeared after it and was defined by "#$brand 0pril 0utomates, resulting of a collaborati&e effort of French companies-enault0utomationandMerlin erinet $ie in 1;8*'1:*+% ifferences between Modbus and


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$onse/uently, entity number does not include the entity type% Foreample, holding register I65515 in Modbus will be holding registerI, located at address in ", calledopen+mbus)+ the master node must routinely poll each field de&ice,and look for changes in the data% his consumes bandwidth andnetwork time in applications where bandwidth may be epensi&e,such as o&er a low+bit+rate radio link%
https://en.wikipedia.org/w/index.php?title=Modbus&action=edit&section=16https://en.wikipedia.org/wiki/Floating_pointhttps://en.wikipedia.org/w/index.php?title=Modbus&action=edit&section=17https://en.wikipedia.org/wiki/Programmable_logic_controllerhttps://en.wikipedia.org/w/index.php?title=Modbus&action=edit&section=16https://en.wikipedia.org/wiki/Floating_pointhttps://en.wikipedia.org/w/index.php?title=Modbus&action=edit&section=17https://en.wikipedia.org/wiki/Programmable_logic_controller


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Modbus is restricted to addressing 486 de&ices on one data link,which limits the number of field de&ices that may be connected to amaster station (once again Ethernet $"9>" being an eception)%

Modbus transmissions must be contiguous which limits the types ofremote communications de&ices to those that can buffer data toa&oid gaps in the transmission%

Modbus protocol itself pro&ides no security against unauthori3edcommands or interception of data%'1;

#rade roup'edit

Modbus 2rgani3ation, >nc% is a trade associationfor the promotion and de&elopment of Modbusprotocol%'4

Modbus Plus'edit

espite the name, Modbus "lus '1is not a &ariant of Modbus% >t is a different protocol, in&ol&ingtokenpassing%

>t is a proprietary specificationof Schneider Electric, though it is unpublished rather than patented% >tis normally implemented using a custom chipseta&ailable only to partners of Schneider%

$eferences'edit

1% L" >mplementation uide?1%5b, s7%1%7

:% ump up ,-emote Modbus Hetwork Monitoring

!% ump up ,


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17% ump up ,Clar1e, mplementation in "ython

>nteresting "erformance comparison of the 7 abo&e mentionedpython modules

cl based Modbus -. dri&er
https://en.wikipedia.org/wiki/Modbus#cite_ref-13http://books.google.com/books?id=ENqyW8fExswC&pg=PA45http://books.google.com/books?id=ENqyW8fExswC&pg=PA45https://en.wikipedia.org/wiki/International_Standard_Book_Numberhttps://en.wikipedia.org/wiki/Special:BookSources/0-7506-5799-5https://en.wikipedia.org/wiki/Modbus#cite_ref-14http://www.csimn.com/CSI_pages/Modbus101.htmlhttp://www.csimn.com/CSI_pages/Modbus101.htmlhttp://www.csimn.com/CSI_pages/Modbus101.htmlhttps://en.wikipedia.org/wiki/Modbus#cite_ref-15http://www2.schneider-electric.com/resources/sites/SCHNEIDER_ELECTRIC/content/live/FAQS/32000/FA32395/es_ES/E0370_Differences%2520between%2520JBUS%2520and%2520MODBUS%2520protocols.dochttp://www2.schneider-electric.com/resources/sites/SCHNEIDER_ELECTRIC/content/live/FAQS/32000/FA32395/es_ES/E0370_Differences%2520between%2520JBUS%2520and%2520MODBUS%2520protocols.dochttps://en.wikipedia.org/wiki/Modbus#cite_ref-16http://french-corporate.com/french-corporate/329/476/337/329476337-RENAULT-AUTOMATION-MERLIN-GERIN-ET-CIE.phphttp://french-corporate.com/french-corporate/329/476/337/329476337-RENAULT-AUTOMATION-MERLIN-GERIN-ET-CIE.phphttps://en.wikipedia.org/wiki/Modbus#cite_ref-17http://www.eurotherm.com/EasysiteWeb/getresource.axd?AssetID=2025&type=full&servicetype=Attachmenthttp://www.eurotherm.com/EasysiteWeb/getresource.axd?AssetID=2025&type=full&servicetype=Attachmenthttp://www.eurotherm.com/EasysiteWeb/getresource.axd?AssetID=2025&type=full&servicetype=Attachmenthttps://en.wikipedia.org/wiki/Modbus#cite_ref-18https://en.wikipedia.org/wiki/International_Standard_Book_Numberhttps://en.wikipedia.org/wiki/Special:BookSources/3-642-04797-1https://en.wikipedia.org/wiki/Special:BookSources/3-642-04797-1https://en.wikipedia.org/wiki/Special:BookSources/3-642-04797-1https://en.wikipedia.org/wiki/Modbus#cite_ref-19http://www.schneider-electric.com/products/us/en/51900-networks-communication-and-radios/51940-fieldbus-and-core-networks/576-modbus-plus/http://www.schneider-electric.com/products/us/en/51900-networks-communication-and-radios/51940-fieldbus-and-core-networks/576-modbus-plus/http://www.schneider-electric.com/products/us/en/51900-networks-communication-and-radios/51940-fieldbus-and-core-networks/576-modbus-plus/https://en.wikipedia.org/w/index.php?title=Modbus&action=edit&section=21https://en.wikipedia.org/w/index.php?title=Modbus&action=edit&section=21http://www.modbus.org/http://www.interlog.com/~speff/usefulinfo/modbus_protocol.pdfhttp://www.modbusbacnet.com/includes/pdf/MODBUS_2010Nov12.pdfhttp://www.globalmultimedia.in/modnet.htmhttp://www.protocessor.com/solutions/Free-Modbus-RTU-Source-Code.phphttps://github.com/sourceperl/MBclienthttp://www.modbusmonitor.com/https://github.com/bashwork/pymodbushttps://github.com/bashwork/pymodbushttps://pypi.python.org/pypi/MinimalModbushttps://code.google.com/p/modbus-tk/http://stackoverflow.com/questions/17081442/python-modbus-libraryhttp://stackoverflow.com/questions/17081442/python-modbus-libraryhttp://wiki.tcl.tk/21150https://en.wikipedia.org/wiki/Modbus#cite_ref-13http://books.google.com/books?id=ENqyW8fExswC&pg=PA45http://books.google.com/books?id=ENqyW8fExswC&pg=PA45https://en.wikipedia.org/wiki/International_Standard_Book_Numberhttps://en.wikipedia.org/wiki/Special:BookSources/0-7506-5799-5https://en.wikipedia.org/wiki/Modbus#cite_ref-14http://www.csimn.com/CSI_pages/Modbus101.htmlhttps://en.wikipedia.org/wiki/Modbus#cite_ref-15http://www2.schneider-electric.com/resources/sites/SCHNEIDER_ELECTRIC/content/live/FAQS/32000/FA32395/es_ES/E0370_Differences%2520between%2520JBUS%2520and%2520MODBUS%2520protocols.dochttps://en.wikipedia.org/wiki/Modbus#cite_ref-16http://french-corporate.com/french-corporate/329/476/337/329476337-RENAULT-AUTOMATION-MERLIN-GERIN-ET-CIE.phphttps://en.wikipedia.org/wiki/Modbus#cite_ref-17http://www.eurotherm.com/EasysiteWeb/getresource.axd?AssetID=2025&type=full&servicetype=Attachmenthttp://www.eurotherm.com/EasysiteWeb/getresource.axd?AssetID=2025&type=full&servicetype=Attachmenthttps://en.wikipedia.org/wiki/Modbus#cite_ref-18https://en.wikipedia.org/wiki/International_Standard_Book_Numberhttps://en.wikipedia.org/wiki/Special:BookSources/3-642-04797-1https://en.wikipedia.org/wiki/Special:BookSources/3-642-04797-1https://en.wikipedia.org/wiki/Modbus#cite_ref-19http://www.schneider-electric.com/products/us/en/51900-networks-communication-and-radios/51940-fieldbus-and-core-networks/576-modbus-plus/http://www.schneider-electric.com/products/us/en/51900-networks-communication-and-radios/51940-fieldbus-and-core-networks/576-modbus-plus/https://en.wikipedia.org/w/index.php?title=Modbus&action=edit&section=21http://www.modbus.org/http://www.interlog.com/~speff/usefulinfo/modbus_protocol.pdfhttp://www.modbusbacnet.com/includes/pdf/MODBUS_2010Nov12.pdfhttp://www.globalmultimedia.in/modnet.htmhttp://www.protocessor.com/solutions/Free-Modbus-RTU-Source-Code.phphttps://github.com/sourceperl/MBclienthttp://www.modbusmonitor.com/https://github.com/bashwork/pymodbushttps://github.com/bashwork/pymodbushttps://pypi.python.org/pypi/MinimalModbushttps://code.google.com/p/modbus-tk/http://stackoverflow.com/questions/17081442/python-modbus-libraryhttp://stackoverflow.com/questions/17081442/python-modbus-libraryhttp://wiki.tcl.tk/21150


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2pen Source $ library of Modbus protocol for #inu, Mac 2S N,Free=S, OHN and Win74

Freeware Modbus Sla&e Simulator 0pplication

Free "eakDM> -., $"9>" and 0$S>> sla&e simulators


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%lectricit( enerationFrom Wikipedia, the free encyclopedia

(-edirected from"ower generation)

urbo generator

$lectricit. generationis the process of generating electric powerfrom other sources ofprimaryenergy% he fundamental principles of electricity generation were disco&ered during the 1;45s andearly 1;75s by the =ritish scientist Michael Faraday%Dis basic method is still used today* electricity isgenerated by the mo&ement of a loop of wire, or disc of copperbetween thepolesof a magnet%'1For electric utilities,it is the first process in the deli&ery of electricity to consumers% he otherprocesses, electricitytransmission,distribution, and electrical power storage and reco&eryusing pumped+storagemethods are normally carried out by theelectric power industry% Electricity ismost often generated at apower stationby electromechanicalgenerators, primarily dri&en by heatenginesfueled by chemicalcombustionornuclear fissionbut also by other means such asthekinetic energyof flowing water and wind% 2ther energy sources includesolar photo&oltaicsand geothermal powerand electrochemicalbatteries%

Contents

'hide

1Distory

4Methods of generating electricity

o 4%1urbines

o 4%4-eciprocating engines

o 4%7"hoto&oltaic panels

o 4%6Electrochemical

o 4%82ther generation methods

7Economics of generation and production of electricity

6"roduction

o 6%1Distorical results of production of electricity

o 6%4"roduction by country
https://en.wikipedia.org/w/index.php?title=Power_generation&redirect=nohttps://en.wikipedia.org/w/index.php?title=Power_generation&redirect=nohttps://en.wikipedia.org/wiki/Turbo_generatorhttps://en.wikipedia.org/wiki/Electric_powerhttps://en.wikipedia.org/wiki/Primary_energyhttps://en.wikipedia.org/wiki/Primary_energyhttps://en.wikipedia.org/wiki/Primary_energyhttps://en.wikipedia.org/wiki/Michael_Faradayhttps://en.wikipedia.org/wiki/Michael_Faradayhttps://en.wikipedia.org/wiki/Faraday_dischttps://en.wikipedia.org/wiki/Faraday_dischttps://en.wikipedia.org/wiki/Magnetic_polehttps://en.wikipedia.org/wiki/Magnethttps://en.wikipedia.org/wiki/Electricity_generation#cite_note-1https://en.wikipedia.org/wiki/Electric_utilityhttps://en.wikipedia.org/wiki/Electric_utilityhttps://en.wikipedia.org/wiki/Electric_power_transmissionhttps://en.wikipedia.org/wiki/Electric_power_transmissionhttps://en.wikipedia.org/wiki/Electric_power_transmissionhttps://en.wikipedia.org/wiki/Electric_power_distributionhttps://en.wikipedia.org/wiki/Pumped-storage_hydroelectricityhttps://en.wikipedia.org/wiki/Electric_power_industryhttps://en.wikipedia.org/wiki/Electric_power_industryhttps://en.wikipedia.org/wiki/Power_stationhttps://en.wikipedia.org/wiki/Power_stationhttps://en.wikipedia.org/wiki/Electrical_generatorhttps://en.wikipedia.org/wiki/Heat_enginehttps://en.wikipedia.org/wiki/Heat_enginehttps://en.wikipedia.org/wiki/Combustionhttps://en.wikipedia.org/wiki/Combustionhttps://en.wikipedia.org/wiki/Combustionhttps://en.wikipedia.org/wiki/Nuclear_fissionhttps://en.wikipedia.org/wiki/Nuclear_fissionhttps://en.wikipedia.org/wiki/Kinetic_energyhttps://en.wikipedia.org/wiki/Kinetic_energyhttps://en.wikipedia.org/wiki/Kinetic_energyhttps://en.wikipedia.org/wiki/Photovoltaicshttps://en.wikipedia.org/wiki/Geothermal_powerhttps://en.wikipedia.org/wiki/Geothermal_powerhttps://en.wikipedia.org/wiki/Battery_(electricity)https://en.wikipedia.org/wiki/Battery_(electricity)https://en.wikipedia.org/wiki/Electricity_generationhttps://en.wikipedia.org/wiki/Electricity_generation#Historyhttps://en.wikipedia.org/wiki/Electricity_generation#Methods_of_generating_electricityhttps://en.wikipedia.org/wiki/Electricity_generation#Turbineshttps://en.wikipedia.org/wiki/Electricity_generation#Reciprocating_engineshttps://en.wikipedia.org/wiki/Electricity_generation#Photovoltaic_panelshttps://en.wikipedia.org/wiki/Electricity_generation#Electrochemicalhttps://en.wikipedia.org/wiki/Electricity_generation#Other_generation_methodshttps://en.wikipedia.org/wiki/Electricity_generation#Economics_of_generation_and_production_of_electricityhttps://en.wikipedia.org/wiki/Electricity_generation#Productionhttps://en.wikipedia.org/wiki/Electricity_generation#Historical_results_of_production_of_electricityhttps://en.wikipedia.org/wiki/Electricity_generation#Production_by_countryhttps://en.wikipedia.org/w/index.php?title=Power_generation&redirect=nohttps://en.wikipedia.org/wiki/Turbo_generatorhttps://en.wikipedia.org/wiki/Electric_powerhttps://en.wikipedia.org/wiki/Primary_energyhttps://en.wikipedia.org/wiki/Primary_energyhttps://en.wikipedia.org/wiki/Michael_Faradayhttps://en.wikipedia.org/wiki/Faraday_dischttps://en.wikipedia.org/wiki/Magnetic_polehttps://en.wikipedia.org/wiki/Magnethttps://en.wikipedia.org/wiki/Electricity_generation#cite_note-1https://en.wikipedia.org/wiki/Electric_utilityhttps://en.wikipedia.org/wiki/Electric_power_transmissionhttps://en.wikipedia.org/wiki/Electric_power_distributionhttps://en.wikipedia.org/wiki/Pumped-storage_hydroelectricityhttps://en.wikipedia.org/wiki/Electric_power_industryhttps://en.wikipedia.org/wiki/Power_stationhttps://en.wikipedia.org/wiki/Electrical_generatorhttps://en.wikipedia.org/wiki/Heat_enginehttps://en.wikipedia.org/wiki/Heat_enginehttps://en.wikipedia.org/wiki/Combustionhttps://en.wikipedia.org/wiki/Nuclear_fissionhttps://en.wikipedia.org/wiki/Kinetic_energyhttps://en.wikipedia.org/wiki/Photovoltaicshttps://en.wikipedia.org/wiki/Geothermal_powerhttps://en.wikipedia.org/wiki/Battery_(electricity)https://en.wikipedia.org/wiki/Electricity_generationhttps://en.wikipedia.org/wiki/Electricity_generation#Historyhttps://en.wikipedia.org/wiki/Electricity_generation#Methods_of_generating_electricityhttps://en.wikipedia.org/wiki/Electricity_generation#Turbineshttps://en.wikipedia.org/wiki/Electricity_generation#Reciprocating_engineshttps://en.wikipedia.org/wiki/Electricity_generation#Photovoltaic_panelshttps://en.wikipedia.org/wiki/Electricity_generation#Electrochemicalhttps://en.wikipedia.org/wiki/Electricity_generation#Other_generation_methodshttps://en.wikipedia.org/wiki/Electricity_generation#Economics_of_generation_and_production_of_electricityhttps://en.wikipedia.org/wiki/Electricity_generation#Productionhttps://en.wikipedia.org/wiki/Electricity_generation#Historical_results_of_production_of_electricityhttps://en.wikipedia.org/wiki/Electricity_generation#Production_by_country


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6%4%1#ist of countries with source of electricity 455;

8$ogeneration

:En&ironmental concerns

!Water consumption

;See also

-eferences

15Eternal links

)istor('editMain article"lectrification

iagram of an electric power system, generation system in red

$entral power stations became economically practical with the de&elopment of alternatingcurrentpower transmission, using powertransformersto transmit power at high &oltage and with lowloss% Electricity has been generated at central stations since 1;;4% he first power plants were run onwater power'4or coal,'7and today, rely mainly on coal, nuclear,natural gas,hydroelectric, windgenerators,andpetroleum,with a small amount from solar energy, tidal power,andgeothermalsources% he use of power+lines and power+poles ha&e been significantly importantin the distribution of electricity%

Met!ods of eneratin electricit('edit

.%S% 4516 Electricity eneration =y ype%'6
https://en.wikipedia.org/wiki/Electricity_generation#List_of_countries_with_source_of_electricity_2008https://en.wikipedia.org/wiki/Electricity_generation#Cogenerationhttps://en.wikipedia.org/wiki/Electricity_generation#Environmental_concernshttps://en.wikipedia.org/wiki/Electricity_generation#Water_consumptionhttps://en.wikipedia.org/wiki/Electricity_generation#See_alsohttps://en.wikipedia.org/wiki/Electricity_generation#Referenceshttps://en.wikipedia.org/wiki/Electricity_generation#External_linkshttps://en.wikipedia.org/w/index.php?title=Electricity_generation&action=edit&section=1https://en.wikipedia.org/w/index.php?title=Electricity_generation&action=edit&section=1https://en.wikipedia.org/wiki/Electrificationhttps://en.wikipedia.org/wiki/Electrificationhttps://en.wikipedia.org/wiki/Alternating_currenthttps://en.wikipedia.org/wiki/Alternating_currenthttps://en.wikipedia.org/wiki/Transformerhttps://en.wikipedia.org/wiki/Transformerhttps://en.wikipedia.org/wiki/Transformerhttps://en.wikipedia.org/wiki/Electricity_generation#cite_note-2https://en.wikipedia.org/wiki/Electricity_generation#cite_note-3https://en.wikipedia.org/wiki/Coalhttps://en.wikipedia.org/wiki/Nuclear_powerhttps://en.wikipedia.org/wiki/Natural_gashttps://en.wikipedia.org/wiki/Natural_gashttps://en.wikipedia.org/wiki/Hydroelectricityhttps://en.wikipedia.org/wiki/Hydroelectricityhttps://en.wikipedia.org/wiki/Wind_generatorhttps://en.wikipedia.org/wiki/Wind_generatorhttps://en.wikipedia.org/wiki/Wind_generatorhttps://en.wikipedia.org/wiki/Petroleumhttps://en.wikipedia.org/wiki/Petroleumhttps://en.wikipedia.org/wiki/Petroleumhttps://en.wikipedia.org/wiki/Solar_energyhttps://en.wikipedia.org/wiki/Tidal_powerhttps://en.wikipedia.org/wiki/Geothermal_powerhttps://en.wikipedia.org/wiki/Geothermal_powerhttps://en.wikipedia.org/w/index.php?title=Electricity_generation&action=edit&section=2https://en.wikipedia.org/wiki/Electricity_generation#cite_note-4https://en.wikipedia.org/wiki/Electricity_generation#cite_note-4https://en.wikipedia.org/wiki/Electricity_generation#List_of_countries_with_source_of_electricity_2008https://en.wikipedia.org/wiki/Electricity_generation#Cogenerationhttps://en.wikipedia.org/wiki/Electricity_generation#Environmental_concernshttps://en.wikipedia.org/wiki/Electricity_generation#Water_consumptionhttps://en.wikipedia.org/wiki/Electricity_generation#See_alsohttps://en.wikipedia.org/wiki/Electricity_generation#Referenceshttps://en.wikipedia.org/wiki/Electricity_generation#External_linkshttps://en.wikipedia.org/w/index.php?title=Electricity_generation&action=edit&section=1https://en.wikipedia.org/wiki/Electrificationhttps://en.wikipedia.org/wiki/Alternating_currenthttps://en.wikipedia.org/wiki/Alternating_currenthttps://en.wikipedia.org/wiki/Transformerhttps://en.wikipedia.org/wiki/Electricity_generation#cite_note-2https://en.wikipedia.org/wiki/Electricity_generation#cite_note-3https://en.wikipedia.org/wiki/Coalhttps://en.wikipedia.org/wiki/Nuclear_powerhttps://en.wikipedia.org/wiki/Natural_gashttps://en.wikipedia.org/wiki/Hydroelectricityhttps://en.wikipedia.org/wiki/Wind_generatorhttps://en.wikipedia.org/wiki/Wind_generatorhttps://en.wikipedia.org/wiki/Petroleumhttps://en.wikipedia.org/wiki/Solar_energyhttps://en.wikipedia.org/wiki/Tidal_powerhttps://en.wikipedia.org/wiki/Geothermal_powerhttps://en.wikipedia.org/w/index.php?title=Electricity_generation&action=edit&section=2https://en.wikipedia.org/wiki/Electricity_generation#cite_note-4


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Sources of electricity in France in 455:'8nuclear powerwas the main source%

here are se&en fundamental methods of directly transforming other forms of energy into electricalenergy*

Static electricity, from the physical separation and transport ofcharge (eamples*triboelectric effectand lightning)

Electromagnetic induction, where anelectrical

generator, dynamooralternatortransforms kinetic energy(energy ofmotion) into electricity% his is the most used form for generatingelectricity and is based on FaradayBs law% >t can be eperimented bysimply rotating a magnet within closed loops of a conductingmaterial (e%g% copper wire)

Electrochemistry, the direct transformation ofchemical energyintoelectricity, as in a battery, fuel cellorner&e impulse

"hoto&oltaic effect, the transformation of light into electrical energy,as in solar cells

hermoelectric effect, the direct con&ersion of temperaturedifferences to electricity, as in thermocouples,thermopiles,and thermionic con&erters%

"ie3oelectric effect, from the mechanical strain ofelectrically anisotropicmolecules or crystals% -esearchers at the .Separtment of EnergyBs #awrence =erkeley Hational #aboratory(=erkeley #ab) ha&e de&eloped a pie3oelectricgenerator sufficientto operate a li/uid crystal displayusing thin films of M17bacteriophage% ':

Huclear transformation, the creation and acceleration of chargedparticles (eamples*beta&oltaicsor alpha particleemission)

Static electricitywas the first form disco&ered and in&estigated, and the electrostatic generatoris stillused e&en in modern de&ices such as the ?an de raaff generatorand MD generators% $hargecarriers are separated and physically transported to a position of increased electric potential% 0lmostall commercial electrical generation is done using electromagnetic induction, in which mechanicalenergyforces an electrical generatorto rotate% here are many different methods of de&eloping themechanical energy, includingheat engines, hydro, wind and tidal power% he direct con&ersionof nuclear potential energyto electricity by beta decayis used only on a small scale% >n a full+si3enuclear power plant, the heat of a nuclear reaction is used to run a heat engine% his dri&es agenerator, which con&erts mechanical energy into electricity by magnetic induction% Most electricgeneration is dri&en byheat engines% he combustion of fossil fuelssupplies most of the heat to

these engines, with a significant fraction fromnuclear fissionand some fromrenewable sources% he
https://en.wikipedia.org/wiki/Electricity_generation#cite_note-5https://en.wikipedia.org/wiki/Electricity_generation#cite_note-5https://en.wikipedia.org/wiki/Nuclear_powerhttps://en.wikipedia.org/wiki/Nuclear_powerhttps://en.wikipedia.org/wiki/Static_electricityhttps://en.wikipedia.org/wiki/Triboelectric_effecthttps://en.wikipedia.org/wiki/Triboelectric_effecthttps://en.wikipedia.org/wiki/Lightninghttps://en.wikipedia.org/wiki/Electromagnetic_inductionhttps://en.wikipedia.org/wiki/Electrical_generatorhttps://en.wikipedia.org/wiki/Electrical_generatorhttps://en.wikipedia.org/wiki/Electrical_generatorhttps://en.wikipedia.org/wiki/Dynamohttps://en.wikipedia.org/wiki/Dynamohttps://en.wikipedia.org/wiki/Alternatorhttps://en.wikipedia.org/wiki/Alternatorhttps://en.wikipedia.org/wiki/Kinetic_energyhttps://en.wikipedia.org/wiki/Faraday's_law_of_inductionhttps://en.wikipedia.org/wiki/Electrochemistryhttps://en.wikipedia.org/wiki/Chemical_energyhttps://en.wikipedia.org/wiki/Chemical_energyhttps://en.wikipedia.org/wiki/Battery_(electricity)https://en.wikipedia.org/wiki/Fuel_cellhttps://en.wikipedia.org/wiki/Fuel_cellhttps://en.wikipedia.org/wiki/Nerve_impulsehttps://en.wikipedia.org/wiki/Nerve_impulsehttps://en.wikipedia.org/wiki/Photovoltaic_effecthttps://en.wikipedia.org/wiki/Solar_cellhttps://en.wikipedia.org/wiki/Thermoelectric_effecthttps://en.wikipedia.org/wiki/Thermocouplehttps://en.wikipedia.org/wiki/Thermopilehttps://en.wikipedia.org/wiki/Thermopilehttps://en.wikipedia.org/wiki/Thermionic_converterhttps://en.wikipedia.org/wiki/Piezoelectric_effecthttps://en.wikipedia.org/wiki/Anisotropichttps://en.wikipedia.org/wiki/Piezoelectrichttps://en.wikipedia.org/wiki/Liquid_crystal_displayhttps://en.wikipedia.org/wiki/Electricity_generation#cite_note-6https://en.wikipedia.org/wiki/Betavoltaicshttps://en.wikipedia.org/wiki/Betavoltaicshttps://en.wikipedia.org/wiki/Alpha_particlehttps://en.wikipedia.org/wiki/Static_electricityhttps://en.wikipedia.org/wiki/Electrostatic_generatorhttps://en.wikipedia.org/wiki/Van_de_Graaff_generatorhttps://en.wikipedia.org/wiki/MHD_generatorhttps://en.wikipedia.org/wiki/Mechanical_energyhttps://en.wikipedia.org/wiki/Mechanical_energyhttps://en.wikipedia.org/wiki/Mechanical_energyhttps://en.wikipedia.org/wiki/Electrical_generatorhttps://en.wikipedia.org/wiki/Heat_enginehttps://en.wikipedia.org/wiki/Heat_enginehttps://en.wikipedia.org/wiki/Nuclear_potential_energyhttps://en.wikipedia.org/wiki/Beta_decayhttps://en.wikipedia.org/wiki/Beta_decayhttps://en.wikipedia.org/wiki/Heat_enginehttps://en.wikipedia.org/wiki/Heat_enginehttps://en.wikipedia.org/wiki/Fossil_fuelhttps://en.wikipedia.org/wiki/Nuclear_fissionhttps://en.wikipedia.org/wiki/Nuclear_fissionhttps://en.wikipedia.org/wiki/Renewable_sourcehttps://en.wikipedia.org/wiki/Renewable_sourcehttps://en.wikipedia.org/wiki/Electricity_generation#cite_note-5https://en.wikipedia.org/wiki/Nuclear_powerhttps://en.wikipedia.org/wiki/Static_electricityhttps://en.wikipedia.org/wiki/Triboelectric_effecthttps://en.wikipedia.org/wiki/Lightninghttps://en.wikipedia.org/wiki/Electromagnetic_inductionhttps://en.wikipedia.org/wiki/Electrical_generatorhttps://en.wikipedia.org/wiki/Electrical_generatorhttps://en.wikipedia.org/wiki/Dynamohttps://en.wikipedia.org/wiki/Alternatorhttps://en.wikipedia.org/wiki/Kinetic_energyhttps://en.wikipedia.org/wiki/Faraday's_law_of_inductionhttps://en.wikipedia.org/wiki/Electrochemistryhttps://en.wikipedia.org/wiki/Chemical_energyhttps://en.wikipedia.org/wiki/Battery_(electricity)https://en.wikipedia.org/wiki/Fuel_cellhttps://en.wikipedia.org/wiki/Nerve_impulsehttps://en.wikipedia.org/wiki/Photovoltaic_effecthttps://en.wikipedia.org/wiki/Solar_cellhttps://en.wikipedia.org/wiki/Thermoelectric_effecthttps://en.wikipedia.org/wiki/Thermocouplehttps://en.wikipedia.org/wiki/Thermopilehttps://en.wikipedia.org/wiki/Thermionic_converterhttps://en.wikipedia.org/wiki/Piezoelectric_effecthttps://en.wikipedia.org/wiki/Anisotropichttps://en.wikipedia.org/wiki/Piezoelectrichttps://en.wikipedia.org/wiki/Liquid_crystal_displayhttps://en.wikipedia.org/wiki/Electricity_generation#cite_note-6https://en.wikipedia.org/wiki/Betavoltaicshttps://en.wikipedia.org/wiki/Alpha_particlehttps://en.wikipedia.org/wiki/Static_electricityhttps://en.wikipedia.org/wiki/Electrostatic_generatorhttps://en.wikipedia.org/wiki/Van_de_Graaff_generatorhttps://en.wikipedia.org/wiki/MHD_generatorhttps://en.wikipedia.org/wiki/Mechanical_energyhttps://en.wikipedia.org/wiki/Mechanical_energyhttps://en.wikipedia.org/wiki/Electrical_generatorhttps://en.wikipedia.org/wiki/Heat_enginehttps://en.wikipedia.org/wiki/Nuclear_potential_energyhttps://en.wikipedia.org/wiki/Beta_decayhttps://en.wikipedia.org/wiki/Heat_enginehttps://en.wikipedia.org/wiki/Fossil_fuelhttps://en.wikipedia.org/wiki/Nuclear_fissionhttps://en.wikipedia.org/wiki/Renewable_source


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modernsteam turbine(in&ented by Sir $harles "arsonsin 1;;6) currently generates about ;5 oftheelectric powerin the world using a &ariety of heat sources%

urbines'edit

#arge dams such ashree orges amin $hina can pro&ide large amounts of hydroelectricpower it has a

44%8 Wcapability%

0lmost all electrical power on Earth is generated with a turbineof some type% urbines are commonlydri&en by wind, water, steam or burning gas% he turbine dri&es an electric generator% "ower sourcesinclude*

+team

Water is boiled bycoalburned in a thermal power plant,about65 of all electricity is generated this way%'!

Huclear fissionheat created in anuclear reactorcreates steam%#ess than 18 of electricity is generated this way%

-enewables% he steam is generated by*

=iomass

Solar thermal energy(the sun as the heat source)*solarparabolic troughsandsolar power towersconcentratesunlight to heat a heat transfer fluid, which is then used toproduce steam%

eothermal power% Either steam under pressure emergesfrom the ground and dri&es a turbine or hot watere&aporates a low boiling li/uid to create &apor to dri&e aturbine%

#arge dams such asDoo&er amcan pro&ide large amounts ofhydroelectricpower it has 4%5!Wcapability%

0asHatural gas is burned in agas turbine, turbines are dri&en

directly by gases produced by combustion%$ombined cyclearedri&en by both steam and natural gas% hey generate power byburning natural gas in a gas turbineand use residual heat to
https://en.wikipedia.org/wiki/Steam_turbinehttps://en.wikipedia.org/wiki/Steam_turbinehttps://en.wikipedia.org/wiki/Steam_turbinehttps://en.wikipedia.org/wiki/Charles_Algernon_Parsonshttps://en.wikipedia.org/wiki/Electric_powerhttps://en.wikipedia.org/wiki/Electric_powerhttps://en.wikipedia.org/wiki/Electric_powerhttps://en.wikipedia.org/w/index.php?title=Electricity_generation&action=edit&section=3https://en.wikipedia.org/wiki/Three_Gorges_Damhttps://en.wikipedia.org/wiki/Three_Gorges_Damhttps://en.wikipedia.org/wiki/Hydroelectrichttps://en.wikipedia.org/wiki/Watt#Gigawatthttps://en.wikipedia.org/wiki/Watt#Gigawatthttps://en.wikipedia.org/wiki/Turbinehttps://en.wikipedia.org/wiki/Electric_generatorhttps://en.wikipedia.org/wiki/Coalhttps://en.wikipedia.org/wiki/Coalhttps://en.wikipedia.org/wiki/Fossil-fuel_power_stationhttps://en.wikipedia.org/wiki/Fossil-fuel_power_stationhttps://en.wikipedia.org/wiki/Electricity_generation#cite_note-7https://en.wikipedia.org/wiki/Nuclear_fissionhttps://en.wikipedia.org/wiki/Nuclear_fissionhttps://en.wikipedia.org/wiki/Nuclear_reactorhttps://en.wikipedia.org/wiki/Nuclear_reactorhttps://en.wikipedia.org/wiki/Nuclear_reactorhttps://en.wikipedia.org/wiki/Biomasshttps://en.wikipedia.org/wiki/Solar_thermal_energyhttps://en.wikipedia.org/wiki/Solar_parabolic_troughhttps://en.wikipedia.org/wiki/Solar_parabolic_troughhttps://en.wikipedia.org/wiki/Solar_parabolic_troughhttps://en.wikipedia.org/wiki/Solar_parabolic_troughhttps://en.wikipedia.org/wiki/Solar_power_towerhttps://en.wikipedia.org/wiki/Solar_power_towerhttps://en.wikipedia.org/wiki/Geothermal_powerhttps://en.wikipedia.org/wiki/Hoover_Damhttps://en.wikipedia.org/wiki/Hoover_Damhttps://en.wikipedia.org/wiki/Hydroelectrichttps://en.wikipedia.org/wiki/Watt#Gigawatthttps://en.wikipedia.org/wiki/Watt#Gigawatthttps://en.wikipedia.org/wiki/Gas_turbinehttps://en.wikipedia.org/wiki/Gas_turbinehttps://en.wikipedia.org/wiki/Combustionhttps://en.wikipedia.org/wiki/Combined_cyclehttps://en.wikipedia.org/wiki/Combined_cyclehttps://en.wikipedia.org/wiki/Combined_cyclehttps://en.wikipedia.org/wiki/Gas_turbinehttps://en.wikipedia.org/wiki/Steam_turbinehttps://en.wikipedia.org/wiki/Charles_Algernon_Parsonshttps://en.wikipedia.org/wiki/Electric_powerhttps://en.wikipedia.org/w/index.php?title=Electricity_generation&action=edit&section=3https://en.wikipedia.org/wiki/Three_Gorges_Damhttps://en.wikipedia.org/wiki/Hydroelectrichttps://en.wikipedia.org/wiki/Watt#Gigawatthttps://en.wikipedia.org/wiki/Turbinehttps://en.wikipedia.org/wiki/Electric_generatorhttps://en.wikipedia.org/wiki/Coalhttps://en.wikipedia.org/wiki/Fossil-fuel_power_stationhttps://en.wikipedia.org/wiki/Electricity_generation#cite_note-7https://en.wikipedia.org/wiki/Nuclear_fissionhttps://en.wikipedia.org/wiki/Nuclear_reactorhttps://en.wikipedia.org/wiki/Biomasshttps://en.wikipedia.org/wiki/Solar_thermal_energyhttps://en.wikipedia.org/wiki/Solar_parabolic_troughhttps://en.wikipedia.org/wiki/Solar_parabolic_troughhttps://en.wikipedia.org/wiki/Solar_power_towerhttps://en.wikipedia.org/wiki/Geothermal_powerhttps://en.wikipedia.org/wiki/Hoover_Damhttps://en.wikipedia.org/wiki/Hydroelectrichttps://en.wikipedia.org/wiki/Watt#Gigawatthttps://en.wikipedia.org/wiki/Gas_turbinehttps://en.wikipedia.org/wiki/Combustionhttps://en.wikipedia.org/wiki/Combined_cyclehttps://en.wikipedia.org/wiki/Gas_turbine


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generate steam% 0t least 45 of the worlds electricity is generatedby natural gas%

aterEnergy is captured from the mo&ement of water% From fallingwater (dam), the rise and fall of tides or ocean thermal currents%Each dri&ing a water turbineto produce approimately 1: of theworlds electricity%

indhe windmillwas a &ery early wind turbine%>n asolar updrafttowerwind is artificially produced% =efore 4515 less than 4 of theworlds electricity was produced from wind%

Reciprocating engines'editSmall electricity generators are often powered byreciprocating enginesburning diesel,biogasornatural gas% iesel enginesare often used for back up generation, usually at low &oltages% Dowe&ermost large power grids also use diesel generators, originally pro&ided as emergency back up for aspecific facility such as a hospital, to feed power into the grid during certain circumstances% =iogas isoften combusted where it is produced, such as a landfill or wastewater treatment plant, with areciprocating engine or a microturbine, which is a small gas turbine%

0 coal+fired power plant in #aughlin, He&ada .%S%0% 2wners of this plant ceased operations after declining to

in&est in pollution control e/uipment to comply with pollution regulations%';

"oto3oltaic panels'edit.nlike the solar heat concentrators mentioned abo&e, photo&oltaic panelscon&ert sunlight directly toelectricity% 0lthough sunlight is free and abundant, solar electricity is still usually more epensi&e toproduce than large+scale mechanically generated power due to the cost of the panels% #ow+efficiencysilicon solar cells ha&e been decreasing in cost and multiJunction cells with close to 75 con&ersionefficiency are now commercially a&ailable% 2&er 65 efficiency has been demonstrated ineperimental systems%'.ntil recently, photo&oltaics were most commonly used in remote siteswhere there is no access to a commercial power grid, or as a supplemental electricity source forindi&idual homes and businesses% -ecent ad&ances in manufacturing efficiency and photo&oltaictechnology, combined with subsidies dri&en by en&ironmental concerns, ha&e dramaticallyaccelerated the deployment of solar panels% >nstalled capacity is growing by 65 per year led by

increases in ermany,


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Wind turbinesusually pro&ide electrical generation in conJunction with other methods of producing power%

?arious other technologies ha&e been studied and de&eloped for power generation%

Solid+state generation (without mo&ing parts) is of particular interest in portable applications% his

area is largely dominated by thermoelectric(E) de&ices, though thermionic(>)andthermophoto&oltaic("?) systems ha&e been de&eloped as well% ypically, E de&ices are usedat lower temperatures than > and "? systems%

"ie3oelectricde&ices are used for power generation from mechanical strain, particularly in powerhar&esting%

=eta&oltaicsare another type of solid+state power generator which produces electricity fromradioacti&e decay% Fluid+basedmagnetohydrodynamic(MD) power generation has been studied asa method for etracting electrical power from nuclear reactorsand also from more con&entional fuelcombustion systems% 2smotic powerfinally is another possibility at places where salt and freshwater merges (e%g% deltas, %%%)

%conomics of eneration and production of electricit('editSee also Cost of electricit) b) sourcehe selection of electricity production modes and their economic &iability &aries in accordance withdemand and region% he economics &ary considerably around the world,resulting in widespreadselling prices, e%g% the price in ?ene3uela is 7 cents per kWh while in enmark it is 65 cents per kWh%Dydroelectric plants, nuclear power plants, thermal power plants and renewable sources ha&e theirown pros and cons, and selection is based upon the local power re/uirement and the fluctuations indemand% 0ll power grids ha&e &arying loads on them but the daily minimum is the base load,supplied by plants which run continuously% Huclear, coal, oil and gas plants can supply base load%

hermal energy is economical in areas of high industrial density, as the high demand cannot be metby renewable sources% he effect of locali3ed pollution is also minimi3ed as industries are usually

located away from residential areas% hese plants can also withstand &ariation in load andconsumption by adding more units or temporarily decreasing the production of some units% Huclearpower plants can produce a huge amount of power from a single unit% Dowe&er, recent disasters int is not an economically&iable source of production where the load &aries too much during the annual production cycle andthe ability to store the flow of water is limited%

ue to ad&ancements in technology, and with mass production, renewable sources other thanhydroelectricity (solar power, wind energy, tidal power, etc%) eperienced decreases in cost ofproduction, and the energy is now in many cases cost+comparati&e with fossil fuels% Manygo&ernments around the world pro&ide subsidies to offset the higher cost of any new power

production, and to make the installation of renewable energy systems economically feasible%Dowe&er, their use is fre/uently limited by theirintermittent nature% >f natural gas prices are below 7
https://en.wikipedia.org/wiki/Wind_turbinehttps://en.wikipedia.org/wiki/Thermoelectricityhttps://en.wikipedia.org/wiki/Thermoelectricityhttps://en.wikipedia.org/wiki/Thermionic_converterhttps://en.wikipedia.org/wiki/Thermionic_converterhttps://en.wikipedia.org/wiki/Thermophotovoltaichttps://en.wikipedia.org/wiki/Thermophotovoltaichttps://en.wikipedia.org/wiki/Thermophotovoltaichttps://en.wikipedia.org/wiki/Piezoelectrichttps://en.wikipedia.org/wiki/Power_harvestinghttps://en.wikipedia.org/wiki/Power_harvestinghttps://en.wikipedia.org/wiki/Betavoltaicshttps://en.wikipedia.org/wiki/MHD_generatorhttps://en.wikipedia.org/wiki/Nuclear_reactorhttps://en.wikipedia.org/wiki/Osmotic_powerhttps://en.wikipedia.org/w/index.php?title=Electricity_generation&action=edit&section=8https://en.wikipedia.org/wiki/Cost_of_electricity_by_sourcehttps://en.wikipedia.org/wiki/Electricity_pricing#Global_electricity_price_comparisonhttps://en.wikipedia.org/wiki/Electricity_pricing#Global_electricity_price_comparisonhttps://en.wikipedia.org/wiki/Intermittent_energy_sourcehttps://en.wikipedia.org/wiki/Wind_turbinehttps://en.wikipedia.org/wiki/Thermoelectricityhttps://en.wikipedia.org/wiki/Thermionic_converterhttps://en.wikipedia.org/wiki/Thermophotovoltaichttps://en.wikipedia.org/wiki/Piezoelectrichttps://en.wikipedia.org/wiki/Power_harvestinghttps://en.wikipedia.org/wiki/Power_harvestinghttps://en.wikipedia.org/wiki/Betavoltaicshttps://en.wikipedia.org/wiki/MHD_generatorhttps://en.wikipedia.org/wiki/Nuclear_reactorhttps://en.wikipedia.org/wiki/Osmotic_powerhttps://en.wikipedia.org/w/index.php?title=Electricity_generation&action=edit&section=8https://en.wikipedia.org/wiki/Cost_of_electricity_by_sourcehttps://en.wikipedia.org/wiki/Electricity_pricing#Global_electricity_price_comparisonhttps://en.wikipedia.org/wiki/Intermittent_energy_source


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per million =ritish thermal units, generating electricity from natural gas is cheaper than generatingpower by burning coal%'11

Production'edit5his section is outdated. 6lease u&date this article to reflect recent eents or ne$l' aail

information. (March 2015)

he production of electricity in 455 was 45,587Wh% Sources of electricity were fossil fuels :!,renewable energy 1: (mainly hydroelectric, wind, solar and biomass), and nuclear power 17, andother sources were 7% he maJority of fossil fuel usage for the generation of electricity was coal andgas% 2il was 8%8, as it is the most epensi&e common commodity used to produce electricalenergy% Hinety+two percent of renewable energy was hydroelectric followed by wind at : andgeothermal at 1%;% Solar photo&oltaic was 5%5:, and solar thermal was 5%556% ata are from2E$ 4511+14 Factbook (455 data)% '14

&ource of Electricity (,orld total year /008!

- oal 1il

"atural

2as "uclear Rene+ables other Total

Aerage electric &o$er (5=h'ear) 8,23 1,111 ,301 2,@31 3,288 8 20,21

Aerage electric &o$er (=) G2. 12.@ G0.@ 311. [email protected] .8 2311.

6ro&ortion 1H H 21H 13H 1H 3H 100H

data source >E092E$

Energy Flow of "ower "lantotal energy consumed at all power plants for the generation ofelectricity was 6,7;,!:; ktoe (kilo ton of oil e/ui&alent) which was7: of the total for primary energy sources ("ES) of 455;%Electricity output (gross) was 1,!78,8! ktoe (45,1;8 Wh),efficiency was 7, and the balance of :1 was generated heat% 0small part (168,161 ktoe, which was 7 of the input total) of theheat was utili3ed at co+generation heat and power plants% he in+house consumption of electricity and power transmission losseswere 4;,:;1 ktoe% he amount supplied to the final consumer was1,668,4;8 ktoe (1:,675 Wh) which was 77 of the total energyconsumed at power plants and heat and powerco+generation($D")

plants%'17
https://en.wikipedia.org/wiki/British_thermal_unithttps://en.wikipedia.org/wiki/Electricity_generation#cite_note-11https://en.wikipedia.org/w/index.php?title=Electricity_generation&action=edit&section=9https://en.wikipedia.org/wiki/Electricity_generation#cite_note-12https://en.wikipedia.org/wiki/Ton_of_oil_equivalenthttps://en.wikipedia.org/wiki/Co-generationhttps://en.wikipedia.org/wiki/Co-generationhttps://en.wikipedia.org/wiki/Electricity_generation#cite_note-13https://en.wikipedia.org/wiki/British_thermal_unithttps://en.wikipedia.org/wiki/Electricity_generation#cite_note-11https://en.wikipedia.org/w/index.php?title=Electricity_generation&action=edit&section=9https://en.wikipedia.org/wiki/Electricity_generation#cite_note-12https://en.wikipedia.org/wiki/Ton_of_oil_equivalenthttps://en.wikipedia.org/wiki/Co-generationhttps://en.wikipedia.org/wiki/Electricity_generation#cite_note-13


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4istorical results of production of electricit.'edit

roduction b. countr.'editMain article &orld ener%) resources and consuption

See also "lectricit) consuption

he .nited States has long been the largest producer andconsumer of electricity, with a global share in 4558 of at least 48,followed by $hina, ndia% 0s of


25/209

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World energy consumption

$eferences'edit

1% ump up ,5Pa%e not found5- Retrieved 82 Ma) *82-

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7% ump up ,5Pearl Street Station5- Retrieved 82 Ma) *82-

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8% ump up ,D"$$jS--EHj0nnej>>%pdfsee page 15 Moomaw,W%, "% =urgherr, % Death, M% #en3en, >* Methodology% >n >"$$ Special -eport on

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https://en.wikipedia.org/wiki/Electricity_generation#cite_ref-3http://www.ieeeghn.org/wiki/index.php/Pearl_Street_Stationhttp://www.ieeeghn.org/wiki/index.php/Pearl_Street_Stationhttps://en.wikipedia.org/wiki/Electricity_generation#cite_ref-4https://en.wikipedia.org/wiki/Electricity_generation#cite_ref-4http://www.eia.gov/electricity/monthly/epm_table_grapher.cfm?t=epmt_1_01http://www.eia.gov/electricity/monthly/epm_table_grapher.cfm?t=epmt_1_01http://www.eia.gov/electricity/monthly/epm_table_grapher.cfm?t=epmt_1_01https://en.wikipedia.org/wiki/Electricity_generation#cite_ref-5http://www.industrie.gouv.fr/energie/statisti/pdf/elec-analyse-stat.pdfhttp://www.industrie.gouv.fr/energie/statisti/pdf/elec-analyse-stat.pdfhttp://www.industrie.gouv.fr/energie/statisti/pdf/elec-analyse-stat.pdfhttp://www.industrie.gouv.fr/energie/statisti/pdf/elec-analyse-stat.pdfhttps://en.wikipedia.org/wiki/Electricity_generation#cite_ref-6http://timesofindia.indiatimes.com/home/science/Electricity-generated-from-harmless-viruses/articleshow/13133756.cmshttp://timesofindia.indiatimes.com/home/science/Electricity-generated-from-harmless-viruses/articleshow/13133756.cmshttp://timesofindia.indiatimes.com/home/science/Electricity-generated-from-harmless-viruses/articleshow/13133756.cmshttps://en.wikipedia.org/wiki/Electricity_generation#cite_ref-7http://www.worldcoal.org/coal/uses-of-coal/coal-electricity/http://www.worldcoal.org/coal/uses-of-coal/coal-electricity/http://www.worldcoal.org/coal/uses-of-coal/coal-electricity/https://en.wikipedia.org/wiki/Electricity_generation#cite_ref-8http://www.planetark.com/dailynewsstory.cfm/newsid/34265/story.htmhttp://www.planetark.com/dailynewsstory.cfm/newsid/34265/story.htmhttp://www.planetark.com/dailynewsstory.cfm/newsid/34265/story.htmhttp://www.planetark.com/dailynewsstory.cfm/newsid/34265/story.htmhttps://en.wikipedia.org/wiki/Electricity_generation#cite_ref-9http://www.doe.gov/news/4503.htmhttp://www.doe.gov/news/4503.htmhttp://www.doe.gov/news/4503.htmhttps://en.wikipedia.org/wiki/Electricity_generation#cite_ref-10http://www.eere.energy.gov/news/archive.cfm/pubDate=%7Bd%20'2003-09-24'%7D#6490http://www.eere.energy.gov/news/archive.cfm/pubDate=%7Bd%20'2003-09-24'%7D#6490http://www.eere.energy.gov/news/archive.cfm/pubDate=%7Bd%20'2003-09-24'%7D#6490https://en.wikipedia.org/wiki/Electricity_generation#cite_ref-11http://www.forbes.com/sites/modeledbehavior/2013/03/22/will-natural-gas-stay-cheap-enough-replace-coal-and-lower-us-carbon-emissions/http://www.forbes.com/sites/modeledbehavior/2013/03/22/will-natural-gas-stay-cheap-enough-replace-coal-and-lower-us-carbon-emissions/http://www.forbes.com/sites/modeledbehavior/2013/03/22/will-natural-gas-stay-cheap-enough-replace-coal-and-lower-us-carbon-emissions/http://www.forbes.com/sites/modeledbehavior/2013/03/22/will-natural-gas-stay-cheap-enough-replace-coal-and-lower-us-carbon-emissions/http://www.forbes.com/sites/modeledbehavior/2013/03/22/will-natural-gas-stay-cheap-enough-replace-coal-and-lower-us-carbon-emissions/https://en.wikipedia.org/wiki/Electricity_generation#cite_ref-12http://www.oecd-ilibrary.org/sites/factbook-2011-en/06/01/04/index.html?contentType=&itemId=/content/chapter/factbook-2011-49-en&containerItemId=/content/serial/18147364&accessItemIds=&mimeType=text/hhttp://www.oecd-ilibrary.org/sites/factbook-2011-en/06/01/04/index.html?contentType=&itemId=/content/chapter/factbook-2011-49-en&containerItemId=/content/serial/18147364&accessItemIds=&mimeType=text/hhttps://en.wikipedia.org/wiki/Electricity_generation#cite_ref-13http://www.iea.org/stats/balancetable.asp?COUNTRY_CODE=29http://www.iea.org/stats/balancetable.asp?COUNTRY_CODE=29https://en.wikipedia.org/wiki/Electricity_generation#cite_ref-Statistics_and_Balances_14-0https://en.wikipedia.org/wiki/Electricity_generation#cite_ref-Statistics_and_Balances_14-0https://en.wikipedia.org/wiki/Electricity_generation#cite_ref-Statistics_and_Balances_14-0https://en.wikipedia.org/wiki/Electricity_generation#cite_ref-Statistics_and_Balances_14-1https://en.wikipedia.org/wiki/Electricity_generation#cite_ref-Statistics_and_Balances_14-1http://www.iea.org/stats/index.asphttps://en.wikipedia.org/wiki/Electricity_generation#cite_ref-15https://www.cia.gov/library/publications/download/https://en.wikipedia.org/wiki/Electricity_generation#cite_ref-HB_16-0https://en.wikipedia.org/wiki/Electricity_generation#CITEREFHunterBryant1991https://en.wikipedia.org/wiki/Electricity_generation#CITEREFHunterBryant1991https://en.wikipedia.org/wiki/Electricity_generation#cite_ref-17http://seattletimes.nwsource.com/html/nationworld/2003732690_carbon03.htmlhttp://seattletimes.nwsource.com/html/nationworld/2003732690_carbon03.htmlhttp://seattletimes.nwsource.com/html/nationworld/2003732690_carbon03.htmlhttps://en.wikipedia.org/wiki/Electricity_generation#cite_ref-18http://www.epa.gov/air/sulfurdioxide/http://www.epa.gov/air/sulfurdioxide/http://www.epa.gov/air/sulfurdioxide/https://en.wikipedia.org/wiki/Electricity_generation#cite_ref-19http://www.epa.gov/cgi-bin/broker?_service=airdata&_program=progs.webprogs.emcatbar.scl&_debug=2&geotype=us&geocode=USA&geoname=United+States&epol=CO+NOX+VOC+SO2+PM25+PM10&years=2002&mapsize=zsc&reqtype=viewmaphttp://www.epa.gov/cgi-bin/broker?_service=airdata&_program=progs.webprogs.emcatbar.scl&_debug=2&geotype=us&geocode=USA&geoname=United+States&epol=CO+NOX+VOC+SO2+PM25+PM10&years=2002&mapsize=zsc&reqtype=viewmaphttps://en.wikipedia.org/wiki/Electricity_generation#cite_ref-20http://www.parliament.uk/edm/2010-12/2061http://www.parliament.uk/edm/2010-12/2061https://en.wikipedia.org/wiki/Electricity_generation#cite_ref-21http://srren.ipcc-wg3.de/report/IPCC_SRREN_Annex_II.pdfhttp://srren.ipcc-wg3.de/report/IPCC_SRREN_Annex_II.pdfhttp://srren.ipcc-wg3.de/report/IPCC_SRREN_Annex_II.pdfhttps://en.wikipedia.org/wiki/Electricity_generation#cite_ref-3http://www.ieeeghn.org/wiki/index.php/Pearl_Street_Stationhttps://en.wikipedia.org/wiki/Electricity_generation#cite_ref-4https://en.wikipedia.org/wiki/Electricity_generation#cite_ref-4http://www.eia.gov/electricity/monthly/epm_table_grapher.cfm?t=epmt_1_01http://www.eia.gov/electricity/monthly/epm_table_grapher.cfm?t=epmt_1_01https://e

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