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megawatt hour

megawatt hour

1 4.0
A unit of energy equal to one million watts used for one hour
  • noun
  • /ˈmɛɡəˌwɑt aʊər/
  • Specialized
translation icon : megavatio hora
  • They expect to generate over 500 megawatt hours of energy each day from the new solar farm.
  • million megawatt hours
  • megawatt hours of power
  • megawatt hours/day

Examples

  • About 200 gallons per megawatt-hour are lost to advanced evaporation of the hot water from the surface of the receiving body.

    Academic text (2011)
  • So the argument can be made that Belews' conventional generation effectively consumes less land per megawatt hour than the Nellis solar array.

    Academic text (2011)
  • Net power generation from all sources was 4,157 million megawatt-hours.

    Academic text (2010)
  • But that is still about 1,100 pounds per megawatt hour for electricity from natural gas.

    Blog text (6)
  • It produces 30,000 megawatt hours (MWh) of power annually, but that only provides 25 percent of the base's annual electrical needs.

    Academic text (2011)
  • The equivalent measure when burning European coal for delivery to Amsterdam, Rotterdam, and Antwerp shows a profit of 14.22 euros a megawatt-hour.

    Blog text (4)
  • German power stations lose 11.25 euros per megawatt-hour from burning gas, according to Bloomberg calculations of the clean-spark spread, which takes into account electricity, fuel, and carbon prices for next month.

    Blog text (4)
  • The estimated cost for this scenario is about $150 per megawatt hour (wholesale), compared to $110 per megawatt hour when nuclear is permitted for otherwise the same modeling selections.

    Blog text (11)
  • Coal-fired electric power generation puts out about twice the amount of carbon dioxide—around 2,000 pounds for every megawatt hour generated—than electricity generated by burning natural gas.

    Blog text (6)
  • By way of comparison, the electrochemical weathering process would sequester 0.8 tonnes of CO2 for every megawatt hour of electricity consumed in the baseline scenario.

    Blog text (28)

Synonyms

MWh
vsmegawatt hour
  • Specialized
4 5.6

A unit of electrical energy equal to one million watt-hours that measures how much electricity is made or used

is the full written unit form rather than the abbreviated symbol
megawatt-hour
vsmegawatt hour
  • Specialized
1 5.1

An amount of electricity equal to one million watts used for one hour

is the same unit spelled without a hyphen in standard writing

How Energetic

megawatt hour
  • Specialized
1 4.0
kilowatt hour
  • Specialized
8 3.2
megajoule
  • Specialized
2 6.0
joule
  • Specialized
11 7.2

Surface Forms

megawatt hour singular

Morphology

megawatt + hour

The meaning is directly compositional: 'megawatt' (a million watts of power) combined with 'hour' (a period of time) yields a unit of energy equal to power multiplied by time. This kind of scientific unit formation is regular and cross-linguistically transparent, so a B1 learner who knows both constituents can readily infer the MWE's meaning.

Etymology

The term megawatt hour combines size and time. mega means 'million', watt is a unit for 'power', and hour is one hour. So one megawatt hour is what you get when one million watts run for one hour, and that's why it measures the 'amount of energy' used.