wikiHydroTimor -- on hydroelectric related terms -- by HydroTimorWatt
Electric power is defined as the amount of work done by an electric current, or the rate at which electrical energy is transmitted. The watt (symbol: W) is the SI derived unit of power, equal to one joule per second. A human climbing a flight of stairs is doing work at the rate of about 200 watts; a highly trained athlete can work at up to approximately 2000 watts for brief periods. An automobile engine produces 25 000 watts (approximately 30 horsepower) while cruising. A typical household incandescent light bulb uses 40 to 100 watts.
One watt is one joule (the SI unit of energy) per second. 1W = 1 newton meter per second = 1V * 1A (if 1 volt of potential difference is applied to a resistive load, and a current of 1 ampere flows, then 1 watt of power is dissipated).
The watt is named after James Watt for his contributions to the development of the steam engine, and was adopted by the Second Congress of the British Association for the Advancement of Science in 1889 and by the 11th Conférence Générale des Poids et Mesures in 1960.
SI multiples:
|
Multiple |
Name |
Symbol |
|
Multiple |
Name |
Symbol |
|
100 |
watt |
W |
|
|
|
|
|
101 |
decawatt |
daW |
|
10–1 |
deciwatt |
dW |
|
102 |
hectowatt |
hW |
|
10–2 |
centiwatt |
cW |
|
103 |
kilowatt |
kW |
|
10–3 |
milliwatt |
mW |
|
106 |
megawatt |
MW |
|
10–6 |
microwatt |
µW |
|
109 |
gigawatt |
GW |
|
10–9 |
nanowatt |
nW |
|
1012 |
terawatt |
TW |
|
10–12 |
picowatt |
pW |
|
1015 |
petawatt |
PW |
|
10–15 |
femtowatt |
fW |
|
1018 |
exawatt |
EW |
|
10–18 |
attowatt |
aW |
|
1021 |
zettawatt |
ZW |
|
10–21 |
zeptowatt |
zW |
|
1024 |
yottawatt |
YW |
|
10–24 |
yoctowatt |
yW |
The kilowatt (symbol: kW) is a unit for measuring power, equal to one thousand watts. A kilowatt is roughly equivalent to 1.34 horsepower.
The megawatt (symbol: MW) is equal to one million (106) watts. The productive capacity of electrical generators operated by utility companies is often measured in MW. A typical modern nuclear power plant produces a peak output on the order of 500 to 2000 MW.
Watt electrical (abbreviation: We) is a term that refers to power produced as electricity. SI prefixes can be used, for example megawatt electrical (MWe) and gigawatt electrical (GWe). Watt thermal (abbreviation: Wt or Wth) refers to thermal power produced; again SI prefixes can be used, for example megawatt thermal (MWt) and gigawatt thermal (GWt). These terms are used to disambiguate the electric output of a thermal power station versus the (larger) thermal output. For example, the Embalse nuclear power plant in Argentina uses a fission reactor to generate 2109 MWt of heat, which creates steam to drive a turbine, which generates 648 MWe of electricity.
for more information we recommend Wikipedia
wikiHydroTimor -- on hydroelectric related terms -- by HydroTimor