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Energy is | Energy is ''work done''. It is [[power]] × time. | ||
Electrical energy is power (most commonly stated in watts) times a unit of time (most commonly | Electrical energy is power (most commonly stated in watts) times a unit of time (most commonly 1 hour: watt-hours). 1,000 watt-hours equals one kilowatt-hour (kWh), which is the amount of power in watts transferred (or used) over 1 hour divided by 1,000. A MWh is equal to 1,000 kWh or 1,000,000 watt-hours. All other metric prefixes can also be applied, e.g., giga (G, billion), tera (T, trillion), and peta (P, quadrillion). | ||
For comparison or inclusion with other forms of energy, electrical energy can also be measured in joules (J), British thermal units (BTUs), and million [ | For comparison or inclusion with other forms of energy, electrical energy can also be measured in joules (J), British thermal units (BTUs), and million tonne<ref>The spelling ''tonne'' is used to specify a metric ton, which is equal to 1,000 kilograms (kg), or 2,205 pounds. A non-metric ''ton'' is equal to 2,000 pounds in the USA (also called a short ton), and 2,240 pounds in the UK (also called a long or imperial ton, equal to 160 [20 × 8] stone).</ref> oil equivalent (mtoe). One petajoule (PJ) = 278 GWh. One quadrillion BTU (quad) = 293 TWh. One mtoe = 11,630 GWh. | ||
The average ''household'' electricity use in the USA was about 11,000 kWh (11 MWh) per year in 2015.<ref>https://www.eia.gov/tools/faqs/faq.php?id=97&t=3</ref> However, residential use represented only 38% of total electricity use in the USA in 2016.<ref>https://www.eia.gov/energyexplained/index.cfm?page=electricity_use</ref> | The average ''household'' electricity use in the USA was about 11,000 kWh (11 MWh) per year in 2015.<ref>https://www.eia.gov/tools/faqs/faq.php?id=97&t=3</ref> However, residential use represented only 38% of total electricity use in the USA in 2016.<ref>https://www.eia.gov/energyexplained/index.cfm?page=electricity_use</ref> | ||